U.S. patent application number 16/095193 was filed with the patent office on 2019-05-16 for polyisocyanurate plastic containing siloxane groups and method for production thereof.
The applicant listed for this patent is COVESTRO DEUTSCHLAND AG. Invention is credited to Thomas KLIMMASCH, Jurgen KOCHER, Hans-Josef LAAS, Jan WEIKARD.
Application Number | 20190144598 16/095193 |
Document ID | / |
Family ID | 55752224 |
Filed Date | 2019-05-16 |
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United States Patent
Application |
20190144598 |
Kind Code |
A1 |
KLIMMASCH; Thomas ; et
al. |
May 16, 2019 |
POLYISOCYANURATE PLASTIC CONTAINING SILOXANE GROUPS AND METHOD FOR
PRODUCTION THEREOF
Abstract
The invention relates to novel polyisocyanurate plastics
containing siloxane groups, which are obtainable by a method
comprising the following steps: al) providing a composition A),
which contains i) oligomeric polyisocyanates B) and compounds
containing silicon C) or ii) contains oligomeric silicon-modified
polyisocyanates D); or iii) contains oligomeric silicon-modified
polyisocyanates D) and oligomeric polyisocyanates B); or iv)
contains oligomeric polyisocyanates B), compounds containing
silicon C) and modified oligomeric polyisocyanates D); or v)
contains compounds containing silicon C) and silicon-modified,
oligomeric polyisocyanates D); a2) catalytic trimerization of the
composition A); wherein the composition A) has a content of monomer
diisocyanates of 20 wt % at maximum. The invention further relates
to the method by which the polyisocyanurate plastics according to
the invention are obtainable, to the use of the polyisocyanurate
plastics according to the invention for producing coatings, films,
semi-finished products, and molded parts, and to substrates coated
by such a coating.
Inventors: |
KLIMMASCH; Thomas;
(Leverkusen, DE) ; WEIKARD; Jan; (Leverkusen,
DE) ; LAAS; Hans-Josef; (Odenthal, DE) ;
KOCHER; Jurgen; (Langenfeld, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
COVESTRO DEUTSCHLAND AG |
Leverkusen |
|
DE |
|
|
Family ID: |
55752224 |
Appl. No.: |
16/095193 |
Filed: |
October 25, 2016 |
PCT Filed: |
October 25, 2016 |
PCT NO: |
PCT/EP2016/075689 |
371 Date: |
October 19, 2018 |
Current U.S.
Class: |
528/28 |
Current CPC
Class: |
C08G 18/168 20130101;
C08G 18/792 20130101; C09D 175/08 20130101; C08G 18/809 20130101;
C08J 5/18 20130101; C08G 18/73 20130101; C08G 18/1816 20130101;
C08G 18/225 20130101; C08G 18/283 20130101; C08G 18/289 20130101;
C08G 18/8064 20130101; C08G 18/022 20130101; C08J 2375/08 20130101;
C08G 18/4833 20130101 |
International
Class: |
C08G 18/80 20060101
C08G018/80; C08G 18/22 20060101 C08G018/22; C08G 18/16 20060101
C08G018/16; C08G 18/73 20060101 C08G018/73 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 21, 2016 |
EP |
16166427.1 |
Claims
1.-20. (canceled)
21. A polyisocyanurate plastic containing siloxane groups,
obtainable by a process comprising the steps of: a1) providing a
composition A) which i) contains oligomeric polyisocyanates B) and
silicon-containing compounds C); or ii) contains oligomeric
silicon-modified polyisocyanates D); or iii) contains oligomeric
silicon-modified polyisocyanates D) and oligomeric polyisocyanates
B); or iv) contains oligomeric polyisocyanates B),
silicon-containing compounds C) and modified oligomeric
polyisocyanates D); or v) contains silicon-containing compounds C)
and silicon-modified, oligomeric polyisocyanates D); a2) catalytic
trimerization of the composition A); wherein the composition A) has
a content of monomeric diisocyanates of not more than 20% by
weight.
22. The polyisocyanurate plastic containing siloxane groups as
claimed in claim 21, characterized in that the silicon-containing
compounds C) has at least one isocyanate-reactive functional
group.
23. The polyisocyanurate plastic containing siloxane groups as
claimed in claim 21, characterized in that the silicon-containing
compounds C) are selected from the group consisting of oligomeric
silicon-modified polyisocyanates D), aminosilanes E),
silane-functional aspartic esters F), silane-functional alkylamides
G), mercaptosilanes H), isocyanatosilanes I) and mixtures
thereof.
24. The polyisocyanurate plastic containing siloxane groups as
claimed in claim 21, characterized in that the silicon-containing
compounds C) and the oligomeric silicon-modified polyisocyanates D)
comprise at least one structural unit selected from the group
consisting of: a) a structural unit of formula (I) ##STR00017##
where R.sup.1, R.sup.2 and R.sup.3 are identical or different
radicals and are each a saturated or unsaturated, linear or
branched, aliphatic or cycloaliphatic or an optionally substituted
aromatic or araliphatic radical having 1 to 18 carbon atoms, which
may optionally contain 1 to 3 heteroatoms from the series of
oxygen, sulfur and nitrogen, X is a linear or branched organic
radical which has at least 1 carbon atom and may optionally contain
1 to 2 imino groups (--NH--), and R.sup.4 is hydrogen, a saturated
or unsaturated, linear or branched, aliphatic or cycloaliphatic or
an optionally substituted aromatic or araliphatic radical having 1
to 18 carbon atoms or a radical of the formula ##STR00018## in
which R.sup.1, R.sup.2, R.sup.3 and X are as defined above; b) a
structural unit of formula (II) ##STR00019## wherein R.sup.1,
R.sup.2 and R.sup.3 are as defined for formula (I), X is a linear
or branched organic radical having at least 1 carbon atom and
R.sup.5 and R.sup.6 are independently saturated or unsaturated,
linear or branched, aliphatic or cycloaliphatic or aromatic organic
radicals which have 1 to 18 carbon atoms, are substituted or
unsubstituted and/or have heteroatoms in the chain; c) a structural
unit of formula (III) ##STR00020## wherein R.sup.1, R.sup.2 and
R.sup.3 are as defined for formula (I), X is a linear or branched
organic radical having at least 1 carbon atom and R.sup.9 is a
saturated linear or branched, aliphatic or cycloaliphatic organic
radical having 1 to 8 carbon atoms; d) a structural unit of formula
(IV) ##STR00021## wherein R.sup.1, R.sup.2 and R.sup.3 are as
defined for formula (I) and Y is a linear or branched organic
radical having at least 1 carbon atom; and e) a structural unit of
formula (V) ##STR00022## wherein R.sup.1, R.sup.2 and R.sup.3 are
as defined for formula (I), and Y is a linear or branched organic
radical having at least 1 carbon atom.
25. The polyisocyanurate plastic containing siloxane groups as
claimed in claim 21, characterized in that said plastic comprises
alkoxysiloxane groups, the silicon-containing compounds C) are
alkoxysilyl-containing compounds C) and the oligomeric
silicon-modified polyisocyanates D) are oligomeric polyisocyanates
D) modified with alkoxysilyl groups.
26. The polyisocyanurate plastic containing siloxane groups as
claimed in claim 21, characterized in that the silicon-containing
compounds C) and the oligomeric silicon-modified polyisocyanates D)
comprise at least one structural unit selected from the group
consisting of: a) a structural unit of formula (I) ##STR00023##
where R.sup.1, R.sup.2 and R.sup.3 are each methyl, methoxy and/or
ethoxy, with the proviso that at least one of the radicals R.sup.1,
R.sup.2 and R.sup.3 is such a methoxy or ethoxy radical, X is a
propylene radical (--CH.sub.2--CH.sub.2--CH.sub.2--), and R.sup.4
is hydrogen, a methyl radical or a radical of formula ##STR00024##
in which R.sup.1, R.sup.2, R.sup.3 and X are as defined above; b) a
structural unit of formula (II) ##STR00025## where R.sup.1,
R.sup.2, R.sup.3 and X wherein R.sup.1, R.sup.2 and R.sup.3 are as
defined for formula (I), R.sup.5 and R.sup.6 are identical or
different radicals and are a methyl-, ethyl-, n-butyl- or
2-ethylhexyl radical; c) a structural unit of formula (III)
##STR00026## where R.sup.1, R.sup.2, R.sup.3 and X wherein R.sup.1,
R.sup.2 and R.sup.3 are as defined for formula (I), R.sup.9 is
hydrogen; d) structural unit of formula (IV) ##STR00027## where
R.sup.1, R.sup.2 and R.sup.3 wherein R.sup.1, R.sup.2 and R.sup.3
are as defined for formula (I), Y is a propylene radical
(--CH.sub.2--CH.sub.2--CH.sub.2--); and e) a structural unit of
formula (V) ##STR00028## wherein R.sup.1, R.sup.2 and R.sup.3 are
as defined for formula (I), and Y is a linear or branched organic
radical having at least 1 carbon atom.
27. The polyisocyanurate plastic containing siloxane groups as
claimed in claim 21, characterized in that the oligomeric
polyisocyanates B) or the oligomeric, silicon-modified
polyisocyanates D) are selected from at least one oligomeric
polyisocyanate having uretdione, isocyanurate, allophanate, biuret,
iminooxadiazinedione or oxadiazinetrione structure or mixtures
thereof.
28. The polyisocyanurate plastic containing siloxane groups as
claimed in claim 21, characterized in that the oligomeric
polyisocyanates B) or the oligomeric, silicon-modified
polyisocyanates D) consist of one or more oligomeric
polyisocyanates formed from 1,5-diisocyanatopentane,
1,6-diisocyanatohexane, isophorone diisocyanate or
4,4'-diisocyanatodicyclohexylmethane or mixtures thereof.
29. The polyisocyanurate plastic containing siloxane groups as
claimed in claim 21, characterized in that the catalytic
trimerization is carried out in the presence of a trimerization
catalyst L), wherein the trimerization catalyst L) preferably
comprises at least one alkali metal or alkaline earth metal
salt.
30. The polyisocyanurate plastic containing siloxane groups as
claimed in claim 29, characterized in that the trimerization
catalyst L) comprises potassium acetate as the alkali metal
salt.
31. The polyisocyanurate plastic containing siloxane groups as
claimed in claim 29, characterized in that the trimerization
catalyst L) comprises a polyether, in particular a polyethylene
glycol.
32. The polyisocyanurate plastic containing siloxane groups as
claimed in claim 21, characterized in that the composition A) has a
content of monomeric diisocyanates of not more than 15% by weight,
not more than 10% by weight or not more than 5% by weight, based in
each case on the weight of the composition A).
33. The polyisocyanurate plastic containing siloxane groups as
claimed in claim 21, characterized in that it constitutes a highly
converted polyisocyanurate plastic containing siloxane groups in
which not more than 20% of the isocyanate groups originally
contained in the composition A) have been preserved.
34. The use of a polyisocyanurate plastic containing siloxane
groups as claimed in claim 21 for producing coatings, films,
semifinished products and moldings.
35. coating, film, semifinished product or molding containing a
polyisocyanurate plastic containing siloxane groups as claimed in
claim 21.
36. A substrate coated with a coating as claimed in claim 35,
wherein the substrate may in particular be selected from a vehicle
body, in particular a goods vehicle or motor vehicle body, and
electronic entertainment devices, such as laptops, tablets or
mobile phones.
37. A process for producing a polyisocyanurate plastic containing
siloxane groups comprising the steps of: a1) providing a
composition A) which i) contains oligomeric polyisocyanates B) and
silicon-containing compounds C); or ii) contains oligomeric
silicon-modified polyisocyanates D); or iii) contains oligomeric
silicon-modified polyisocyanates D) and oligomeric polyisocyanates
B); or iv) contains oligomeric polyisocyanates B),
silicon-containing compounds C) and modified oligomeric
polyisocyanates D); or v) contains silicon-containing compounds C)
and silicon-modified, oligomeric polyisocyanates D); a2) catalytic
trimerization of the composition A); wherein the composition A) has
a content of monomeric diisocyanates of not more than 20% by
weight.
38. The process as claimed in claim 37, characterized in that the
catalytic trimerization is carried out in the presence of a
trimerization catalyst L) which is defined as in claim 29.
39. The process as claimed in claim 37, characterized in that the
silicon-containing compounds C) and/or the oligomeric,
silicon-modified polyisocyanates D) are defined as in claim 22
and/or in that the composition A) is defined as in claim 32.
40. The process as claimed in claim 37, characterized in that the
catalytic trimerization is continued at least up to a degree of
conversion at which only not more than 20% of the isocyanate groups
originally contained in the composition A) remain present, so that
a highly converted polyisocyanurate plastic containing siloxane
groups is obtained.
Description
[0001] The invention relates to a siloxane-containing
polyisocyanurate plastic, to a process for production thereof, to
the use thereof for producing coatings, films, semifinished
products or moldings and also to substrates coated with such a
coating.
[0002] Siloxane-containing polyurethane plastics produced from
alkoxysilyl-containing polyisocyanates and polyols have long been
known. They are used in particular for producing
chemicals-resistant and scratch-resistant coatings for OEM
production line finishing and automotive refinishing. The curing of
such coatings is effected by the urethanization reaction of the
isocyanate groups of the alkoxysilyl-containing polyisocyanate with
the hydroxyl groups of the polyol and also by hydrolysis and
condensation of the alkoxysilyl groups to afford siloxane
groups.
[0003] EP 1 273 640 A1 describes a solvent-containing thermally
curable two-component polyurethane automotive clearcoat/topcoat
having improved scratch resistance which is obtainable by using
silicon-modified polyisocyanates as isocyanate crosslinker
components. The silicon-modified polyisocyanates are obtained by
reaction of aliphatic and/or cycloaliphatic polyisocyanates with
N,N-bis(trialkoxysilylpropyl)amines. Alternatively,
silicon-modified polyisocyanates may also be produced by partial
reaction of monomeric diisocyanates, such as HDI or IPDI, with
N,N-bis(trialkoxysilylpropyl)amines and subsequent oligomerization.
In this latter method of production of the silicon-modified
polyisocyanates the subsequent oligomerization specifically does
not form highly converted, crosslinked siloxane-containing
polyisocyanurate plastics but rather only oligomeric,
low-viscosity, soluble products.
[0004] A series of further publications, for example WO 2008/074489
A1, WO 2008/074490 A1, WO 2010/149236 A1, WO 2014/086-530 A1 and WO
2009/156148 A1, likewise describe coating compositions for
producing weather-resistant, scratch-resistant polyurethane
clearcoat layers for OEM production line finishing and automotive
refinishing in which as the isocyanate crosslinker component
silicon-modified polyisocyanates are used.
[0005] The disadvantage in all of these cases is that not only
isocyanate groups and hydroxyl groups but also alkoxysilyl groups
and hydroxyl groups must be stored separately from one another in
different components and typically mixed with one another only
immediately before application since the recited groups can react
with one another even under customary storage conditions.
[0006] The curing of highly scratch-resistant coatings by catalytic
condensation of alkoxysilyl-containing compounds is described for
example in S. Hofacker et al., Progress in Organic Coatings 45
(2002), 159-164.
[0007] Since the curing mechanism of the alkoxysilyl groups
proceeds via a condensation reaction with the elimination of the
corresponding alcohol a considerable volume shrinkage occurs.
[0008] Strains, tears and loss of adhesion can therefore result.
Furthermore, in coatings technology, for example, coatings which
undergo severe shrinking are known to telegraph roughness and
surface structures of the substrate, which can lead to a loss of
shine and other disruptions to the appearance of the coating.
[0009] The siloxane-containing polyurethane plastics known from the
prior art thus have the essential disadvantage that to achieve high
network densities either a high volume shrinkage has to be suffered
due to excessive elimination of constituents during curing or when
using polyaddition reactions (for example by urethane formation)
the achievement of high network densities becomes difficult.
However, a minimum requirement that results is that of handling two
components during storage.
[0010] Polymers having polyisocyanurate structure are known for
their high mechanical strength. The present processes known from
the prior art for producing such highly converted polyisocyanurate
plastics often proceed from liquid monomeric diisocyanates. On
account of the high exothermicity of the trimerization reaction to
afford polyisocyanurates (-75 kJ/mol NCO), a reaction proceeding
from monomeric diisocyanates, particularly in the case of monomeric
diisocyanates having a high isocyanate content (e.g. BDI, PDI, HDI,
TIN), is typically not possible on a large scale but only in small
amounts of substance under strict temperature control.
[0011] WO 2015/166983 describes the use of polyisocyanurates
plastics for encapsulation of LEDs. The use of silicon-modified
polyisocyanates is not disclosed.
[0012] While U.S. Pat. No. 6,133,397 describes the use of
oligomeric polyisocyanates for forming coatings it does not
disclose silicon-modified coatings.
[0013] Temperature control during the production of highly
converted polyisocyanurates is of enormous importance since, due to
the high isocyanate contents of the monomeric starting materials
and the exothermic reaction, temperatures of more than 300.degree.
C. can arise, which can result in direct decomposition of the
products and even in in situ evaporation of the monomeric
diisocyanates. In addition to the occupational hygiene
disadvantages due to the liberated toxic monomeric diisocyanates or
decomposition products, the formation of blisters and
discolorations in the finished polyisocyanurate plastic is very
disruptive here.
[0014] Consequently, polyisocyanurates have hitherto usually only
found practical applications as crosslinking agents in paint
chemistry, the production of which involves stopping the
trimerization reaction at low conversions and removing excess
unreacted monomeric diisocyanate. Thus, DE 31 00 263; GB 952 931,
GB 966 338; U.S. Pat. Nos. 3,211,703, 3,330,828 envisage conducting
the reaction either in dilution or only up to low conversion values
with very precise temperature control during the production of
crosslinking agents based on isocyanurates starting from aliphatic
and mixed aliphatic and aromatic monomeric diisocyanates. Here too
highly converted polyisocyanurate plastics are specifically not
formed, but rather only oligomeric, low-viscosity, soluble
products.
[0015] For a number of applications, for example for automotive
refinishing and in particular OEM production line finishing and
also for coating of electronic entertainment devices, in particular
laptops, tablets and mobile phones, there is a constant demand in
the market for coating compositions having further-improved scratch
resistance.
[0016] The problem addressed by the present invention was
accordingly that of providing novel siloxane-containing
polyisocyanurate plastics having improved properties, in particular
improved scratch resistance and chemicals resistance and wear
resistance, which are suitable in particular for automotive
finishing and for the coating of electronic entertainment devices
and may be handled in one-component form.
[0017] This problem is solved in accordance with the invention by
the polyisocyanurate plastic specified in claim 1, by the uses and
articles of manufacture specified in claims 14 to 16 and by the
process specified in claim 17.
[0018] Advantageous configurations of the invention are specified
in the dependent claims and are elucidated in detail hereinafter,
as is the general concept of the invention.
[0019] The invention provides a polyisocyanurate plastic containing
siloxane groups, obtainable by a process comprising the steps of:
[0020] a1) providing a composition A) which [0021] i) contains
oligomeric polyisocyanates B) and silicon-containing compounds C);
or [0022] ii) contains oligomeric silicon-modified polyisocyanates
D); or [0023] iii) contains oligomeric silicon-modified
polyisocyanates D) and oligomeric polyisocyanates B); or [0024] iv)
contains oligomeric polyisocyanates B), silicon-containing
compounds C) and modified oligomeric polyisocyanates D); or [0025]
v) contains silicon-containing compounds C) and silicon-modified,
oligomeric polyisocyanates D); [0026] a2) catalytic trimerization
of the composition A); wherein the composition A) has a content of
monomeric diisocyanates of not more than 20% by weight.
[0027] The invention also further provides the abovementioned
process from which the polyisocyanurate plastics of the invention
are obtainable. Also forming part of the subject matter of the
invention, moreover, is the use of the polyisocyanurate plastics
according to the invention for producing coatings, films,
semifinished products and moldings and also substrates coated with
the polyisocyanurate plastic according to the invention.
[0028] The invention more particularly elucidated hereinbelow is
based on the surprising observation that a composition containing
oligomeric polyisocyanates and silicon-containing compounds and/or
oligomeric silicon-modified polyisocyanates may be cured by
catalytic trimerization in such a way that simultaneously with or
before hydrolysis/condensation of silicon-containing functional
groups of the silicon-containing compounds and/or of the
silicon-modified polyisocyanates to afford siloxane groups,
isocyanate groups of the oligomeric polyisocyanates and/or of the
silicon-modified polyisocyanates react to afford polyisocyanurates
by trimerization, thus forming highly crosslinked, highly converted
polyisocyanurate plastics having novel properties. This dual curing
mechanism results in a novel crosslinking structure in the
obtainable polyisocyanurate plastic, said plastic therefore
differing structurally from the materials known from the prior
art.
[0029] The use of compositions containing oligomeric
polyisocyanates and silicon-containing compounds and/or oligomeric,
silicon-modified polyisocyanates instead of monomeric diisocyanates
as starting materials for producing polyisocyanurate plastics
moreover has the advantage that on account of the low isocyanate
contents of the oligomeric reactants a markedly lower heat of
reaction requires removal during curing which in particular also
facilitates the production of large-volume components.
[0030] A "polyisocyanurate plastic" as used herein is a plastic
containing polyisocyanurate. It may also consist predominantly of a
polyisocyanurate. Blends composed of polyisocyanurates and other
plastics are likewise covered by the term "polyisocyanurate
plastic" as used here.
[0031] When reference is made here to "plastic", this means a
product which is very substantially dimensionally stable at room
temperature--in contrast, for example, to gels or liquids. The term
"plastic", as used here, comprises all customary classes of
plastic, i.e. in particular including thermosets, thermoplastics
and elastomers.
[0032] A "polyisocyanurate" as used here is any molecule,
preferably a polymer, having a plurality of isocyanurate structural
units, for example at least 10 isocyanurate structural units. A
molecule having a single isocyanurate structural unit can be
referred to as "isocyanurate".
[0033] The characteristic cyclic isocyanurate structural unit is
shown in the following structural formula:
##STR00001##
[0034] Isocyanurates and polyisocyanurates can be obtained by
cyclotrimerization of polyisocyanates. The conventionally operated
cyclotrimerization proceeding from monomeric diisocyanates is--as
described above--a strongly exothermic reaction. This can
considerably restrict the use options and the levels of
trimerization that are still achievable industrially and
efficiently.
[0035] The term "polyisocyanate" as used here is a collective term
for compounds containing two or more isocyanate groups (this is
understood by the person skilled in the art to mean free isocyanate
groups of the general structure --N.dbd.C.dbd.O) in the molecule.
The simplest and most important representatives of these
polyisocyanates are the diisocyanates. These have the general
structure O.dbd.C.dbd.N--R--N.dbd.C.dbd.O where R typically
represents aliphatic, alicyclic and/or aromatic radicals.
[0036] Because of the polyfunctionality (.gtoreq.2 isocyanate
groups), it is possible to use polyisocyanates to produce a
multitude of polymers (e.g. polyurethanes, polyureas and
polyisocyanurates) and low molecular weight compounds (for example
those having uretdione, isocyanurate, allophanate, biuret,
iminooxadiazinedione and/or oxadiazinetrione structure).
[0037] Where reference is made here to "polyisocyanates" in general
terms, this means monomeric and/or oligomeric polyisocyanates
alike. For the understanding of many aspects of the invention,
however, it is important to distinguish between monomeric
diisocyanates and oligomeric polyisocyanates. Where reference is
made here to "oligomeric polyisocyanates", this means
polyisocyanates formed from at least two monomeric diisocyanate
molecules, i.e. compounds that constitute or contain a reaction
product formed from at least two monomeric diisocyanate
molecules.
[0038] The production of oligomeric polyisocyanates from monomeric
diisocyanates is also referred to here as oligomerization of
monomeric diisocyanates. This "oligomerization" as used here means
the reaction of monomeric diisocyanates to give oligomeric
polyisocyanates having uretdione, isocyanurate, allophanate,
thioallophanate, biuret, iminooxadiazinedione and/or
oxadiazinetrione structure.
[0039] For example, hexamethylene diisocyanate (HDI) is a
"monomeric diisocyanate" since it contains two isocyanate groups
and is not a reaction product formed from at least two
polyisocyanate molecules:
##STR00002##
[0040] Reaction products which are formed from at least two HDI
molecules and still have at least two isocyanate groups, by
contrast, are "oligomeric polyisocyanates" within the context of
the invention. Representatives of such "oligomeric polyisocyanates"
are, proceeding from monomeric HDI, for example, HDI isocyanurate
and HDI biuret, each of which are formed from three monomeric HDI
units:
##STR00003##
[0041] In the context of the invention the term "siloxane group"
describes a group formed by hydrolysis/condensation of
silicon-containing functional groups of the silicon-containing
compounds and/or of the silicon-modified polyisocyanates. The term
"siloxane" as used here is a designation for compounds of general
structure --[SiR.sub.2--O--SiR.sub.2].sub.n--, wherein R typically
represents a hydrogen atom, an alkyl group, an alkoxy group or an
--O--SiR.sub.2-- radical where R is as defined above.
[0042] The polyisocyanurate plastic according to the invention
containing siloxane groups is obtainable by the process according
to the invention. Described hereinbelow therefore are embodiments
relevant both to the inventive polyisocyanurate plastic containing
siloxane groups obtainable by the process according to the
invention and to the process according to the invention as
such.
[0043] According to the invention the composition A) used as
reactant for producing the siloxane-containing polyisocyanurate
plastic according to the invention is low in monomers (i.e. low in
monomeric diisocyanates) and already contains oligomeric
polyisocyanates B), silicon-containing compounds C) or oligomeric
silicon-modified polyisocyanates D) or oligomeric silicon-modified
polyisocyanates D) and oligomeric polyisocyanates B) or oligomeric
polyisocyanates B), silicon-containing compounds C) and modified
oligomeric polyisocyanates D) or silicon-containing compounds C)
and silicon-modified, oligomeric polyisocyanates D).
[0044] In one embodiment of the invention the composition A)
contains oligomeric polyisocyanates B), silicon-containing
compounds C) and/or oligomeric silicon-modified polyisocyanates D)
in amounts such that the composition A) has an NCO content of 5.0%
to 23.5% by weight and a silicon content (calculated with an Si
molecular weight of 28.g/mol) of 0.1% to 30% by weight.
[0045] The presence of oligomeric polyisocyanates B),
silicon-containing compounds C) and/or oligomeric, silicon-modified
polyisocyanates D) provided for in accordance with the invention
and the resulting NCO and Si contents relate to the composition A)
provided originally, i.e. before commencement of the catalytic
trimerization.
[0046] The process according to the invention forms
siloxane-containing polyisocyanurate plastics having a homogeneous
distribution of the siloxane groups in the polyisocyanurate
plastic, i.e. the product is not a polyisocyanurate plastic
modified with silicon-containing compounds C) exclusively at the
surface.
[0047] The terms "low in monomers" and "low in monomeric
diisocyanates" are here used synonymously in relation to the
composition A).
[0048] Results of particular practical relevance are established
when the composition A) has a proportion of monomeric diisocyanates
in the composition A) of not more than 20% by weight, especially
not more than 15% by weight or not more than 10% by weight, based
in each case on the weight of the composition A). It is preferable
when the composition A) has a content of monomeric diisocyanates of
not more than 5% by weight, preferably not more than 2.0% by
weight, particularly preferably not more than 1.0% by weight, based
in each case on the weight of the composition A). Particularly good
results are established when the composition A) is essentially free
of monomeric diisocyanates. "Essentially free" here means that the
content of monomeric diisocyanates is not more than 0.5% by weight,
based on the weight of the composition A).
[0049] It is essential to the invention that the composition A)
used is low in monomers. In practice this can be achieved in
particular when the composition A) contains oligomeric
polyisocyanates B) and/or oligomeric silicon-modified
polyisocyanates D) in whose production the actual oligomerization
reaction is in each case followed by at least one further process
step for removal of unconverted excess monomeric diisocyanates
and/or monomeric, silicon-modified diisocyanates. In a manner of
particular practical relevance, this monomer removal can be
effected by processes known per se, preferably by thin-film
distillation under high vacuum or by extraction with suitable
solvents that are inert toward isocyanate groups, for example
aliphatic or cycloaliphatic hydrocarbons such as pentane, hexane,
heptane, cyclopentane or cyclohexane.
[0050] In a preferred embodiment of the invention the oligomeric
polyisocyanates B) are obtained by oligomerization of monomeric
diisocyanates with subsequent removal of unconverted monomers.
[0051] The processes for producing polyisocyanurate plastics
described in the prior art use very substantially monomeric
diisocyanates as reactants, i.e. pure monomeric diisocyanates or
monomer-rich polyisocyanate compositions are catalytically
trimerized. By contrast, the inventive use, or the "provision" of a
low-monomer composition A) already containing oligomeric
polyisocyanates B) and/or oligomeric, silicon-modified
polyisocyanates D), surprisingly leads to markedly lower volume
shrinkage. The relatively low exothermicity of the inventive
reaction additionally allows polyisocyanurate plastics with a high
conversion level to be obtained.
[0052] Preferably, no monomeric diisocyanate is used in the
trimerization reaction of the invention. However, in one particular
embodiment of the invention the composition A) may comprise an
outside monomeric diisocyanate. In this context, "outside monomeric
diisocyanate" means that said diisocyanate differs from the
monomeric diisocyanates used for producing the oligomeric
polyisocyanates B) and/or the oligomeric silicon-modified
polyisocyanates D) present in the composition A). Addition of
outside monomeric diisocyanate may be advantageous for achievement
of special technical effects, for example an exceptional hardness.
Results of particular practical relevance are established when the
composition A) has a proportion of outside monomeric diisocyanate
in the composition A) of not more than 20% by weight, especially
not more than 15% by weight or not more than 10% by weight, based
in each case on the weight of the composition A). It is preferable
when the composition A) has a content of outside monomeric
diisocyanate of not more than 5% by weight, preferably not more
than 2.0% by weight, particularly preferably not more than 1.0% by
weight, based in each case on the weight of the composition A).
[0053] In a further particular embodiment of the invention, the
composition A) may contain monomeric monoisocyanates or monomeric
isocyanates having an isocyanate functionality greater than two,
i.e. having more than two isocyanate groups per molecule. The
addition of monomeric monoisocyanates or monomeric isocyanates
having an isocyanate functionality greater than two has been found
to be advantageous in order to influence the network density of the
polyisocyanurate plastic. Results of particular practical relevance
are established when the composition A) has a proportion of
monomeric monoisocyanates or monomeric isocyanates having an
isocyanate functionality greater than two in the composition A) of
not more than 20% by weight, especially not more than 15% by weight
or not more than 10% by weight, based in each case on the weight of
the composition A). It is preferable when the composition A) has a
content of monomeric monoisocyanates or monomeric isocyanates
having an isocyanate functionality greater than two of not more
than 5% by weight, preferably not more than 2.0% by weight,
particularly preferably not more than 1.0% by weight, based in each
case on the weight of the composition A). Preferably, no monomeric
monoisocyanate or monomeric isocyanate having an isocyanate
functionality greater than two is used in the trimerization
reaction of the invention.
[0054] The oligomeric polyisocyanates B) are typically obtained by
oligomerization of simple aliphatic, cycloaliphatic, araliphatic
and/or aromatic monomeric diisocyanates or mixtures of such
monomeric diisocyanates.
[0055] The oligomeric polyisocyanates B) and/or oligomeric
silicon-modified polyisocyanates D) may, in accordance with the
invention, especially have uretdione, isocyanurate, allophanate,
thioallophanate, biuret, iminooxadiazinedione and/or
oxadiazinetrione structure. In one embodiment of the invention, the
oligomeric polyisocyanates B) and/or oligomeric silicon-modified
polyisocyanates D) have at least one of the following oligomeric
structure types or mixtures thereof:
##STR00004##
[0056] In a particularly preferred embodiment of the invention the
oligomeric polyisocyanates B) contain at least one structure
selected from the group consisting of uretdione, isocyanurate,
biuret, iminooxadiazinedione and oxadiazinetrione but are
essentially allophanate-free. In this context the term
"allophanate-free" means that the molar ratio of allophanate groups
to all of the abovementioned groups present in the oligomeric
polyisocyanate B) is preferably less than 1:99. It is more
preferable when the molar ratio of allophanate groups to
isocyanurate groups is below 1:99. It is particularly preferable
when the oligomeric polyisocyanate B) contains no allophanate
groups. All of the other definitions given hereinabove in relation
to the oligomeric polyisocyanate B, also apply to this
embodiment.
[0057] It has been found that, surprisingly, it can be advantageous
to use oligomeric polyisocyanates B) and/or oligomeric
silicon-modified polyisocyanates D) that constitute a mixture of at
least two oligomeric polyisocyanates B) and/or at least two
oligomeric silicon-modified polyisocyanates D) where the at least
two oligomeric polyisocyanates B) and/or the at least two
oligomeric silicon-modified polyisocyanates D) differ in terms of
their structure. This structure is preferably selected from the
group consisting of uretdione, isocyanurate, allophanate,
thioallophanate, biuret, iminooxadiazinedione and oxadiazinetrione
structures, and mixtures thereof. Particularly compared to
trimerization reactions with oligomeric polyisocyanates B) and/or
oligomeric silicon-modified polyisocyanates D) of just one defined
structure, starting mixtures of this kind can lead to an effect on
the Tg value, which is advantageous for many applications.
[0058] It is preferable to employ in accordance with the invention
a composition A) containing oligomeric polyisocyanates B) and/or
oligomeric, silicon-modified polyisocyanates D) having biuret,
allophanate, thioallophanate, isocyanurate and/or
iminooxadiazinedione structure and mixtures thereof.
[0059] In another embodiment, the composition A) is one containing
oligomeric polyisocyanates B) and/or oligomeric silicon-modified
polyisocyanates D) of only a single defined oligomeric structure,
for example exclusively or for the most part isocyanurate
structure. However, as a consequence of production the composition
A) generally always contains oligomeric polyisocyanates B) and/or
oligomeric silicon-modified polyisocyanates D) of a plurality of
different oligomeric structures simultaneously.
[0060] According to the invention in a further embodiment
oligomeric polyisocyanates B) and/or oligomeric silicon-modified
polyisocyanates D) of a single defined oligomeric structure are
used, the oligomeric structure being selected from uretdione,
isocyanurate, allophanate, thioallophanate, biuret,
iminooxadiazinedione and/or oxadiazinetrione structure.
[0061] In a further embodiment, the oligomeric polyisocyanates B)
and/or oligomeric silicon-modified polyisocyanates D) are those
which have mainly isocyanurate structure and which may contain the
abovementioned uretdione, allophanate, thioallophanate, biuret,
iminooxadiazinedione and/or oxadiazinetrione structure only as
by-products.
[0062] It is likewise possible in accordance with the invention to
use oligomeric polyisocyanates B) and/or oligomeric
silicon-modified polyisocyanates D) having very substantially no
isocyanurate structure, and containing mainly at least one of the
abovementioned uretdione, allophanate, biuret, iminooxadiazinedione
and/or oxadiazinetrione structure types. In a particular embodiment
of the invention the composition A) contains oligomeric
polyisocyanates B) and/or oligomeric, silicon-modified
polyisocyanates D) having a structure type selected from the group
consisting of uretdione, allophanate, thioallophanate, biuret,
iminooxadiazinedione and/or oxadiazinetrione structure.
[0063] The uretdione, isocyanurate, allophanate, thioallophanate,
biuret, iminooxadiazinedione and/or oxadiazinetrione structure in
the oligomeric polyisocyanates B) and/or the oligomeric
silicon-modified polyisocyanates D) can be determined, for example,
by NMR spectroscopy.
[0064] It is possible here with preference to use .sup.13C NMR
spectroscopy, preferably in proton-decoupled form, since the
oligomeric structures mentioned give characteristic signals.
[0065] Irrespective of the underlying oligomeric structure type
(uretdione, isocyanurate, allophanate, thioallophanate, biuret,
iminooxadiazinedione and/or oxadiazinetrione structure) the
oligomeric polyisocyanates B) present in accordance with the
invention in the composition A) preferably have an (average) NCO
functionality of 2.0 to 5.0, preferably of 2.3 to 4.5. Irrespective
of the underlying oligomeric structure type (uretdione,
isocyanurate, allophanate, thioallophanate biuret,
iminooxadiazinedione and/or oxadiazinetrione structure) the
oligomeric, silicon-modified polyisocyanates D) present according
to the invention in the composition A) preferably have an (average)
NCO functionality of 1.8 to 6.0, preferably of 2.0 to 5.0.
[0066] Results of particular practical relevance are established
when the composition A) to be used in accordance with the invention
has a content of isocyanate groups of 6.0% to 23.0% by weight. It
has been found to be of particular practical relevance when the
composition A) according to the invention has a content of
isocyanate groups of 10.0% to 21.5% by weight, based in each case
on the weight of the composition A).
[0067] Production processes for the oligomeric polyisocyanates B)
having uretdione, isocyanurate, allophanate, thioallophanate,
biuret, iminooxadiazinedione and/or oxadiazinetrione structure to
be used according to the invention in the low-monomer composition
A) are described, for example, in J. Prakt. Chem. 336 (1994)
185-200, in DE-A 1 670 666, DE-A 1 954 093, DE-A 2 414 413, DE-A 2
452 532, DE-A 2 641 380, DE-A 3 700 209, DE-A 3 900 053 and DE-A 3
928 503 or in EP-A 0 336 205, EP-A 0 339 396 and EP-A 0 798
299.
[0068] In an additional or alternative embodiment of the invention,
the composition A) according to the invention is defined in that it
contains oligomeric polyisocyanates B) which have been obtained
from monomeric diisocyanates, irrespective of the nature of the
oligomerization reaction used, with observation of an
oligomerization level of 5% to 45%, preferably 10% to 40%, more
preferably 15% to 30%. "Oligomerization level" is understood here
to mean the percentage of isocyanate groups originally present in
the starting mixture which are consumed during the production
process to form uretdione, isocyanurate, allophanate, biuret,
iminooxadiazinedione and/or oxadiazinetrione structures.
[0069] Suitable monomeric polyisocyanates for producing the
oligomeric polyisocyanates B) are any desired polyisocyanates
obtainable in various ways, for example by phosgenation in the
liquid or gas phase or by a phosgene-free route, for example by
thermal urethane cleavage.
[0070] Particularly good results are established when the
polyisocyanates are monomeric diisocyanates. Preferred monomeric
diisocyanates are those having a molecular weight in the range from
140 to 400 g/mol, having aliphatically, cycloaliphatically,
araliphatically and/or aromatically bonded isocyanate groups, for
example 1,4-diisocyanatobutane (BDI), 1,5-diisocyanatopentane
(PDI), 1,6-diisocyanatohexane (HDI),
2-methyl-1,5-diisocyanatopentane,
1,5-diisocyanato-2,2-dimethylpentane, 2,2,4- or
2,4,4-trimethyl-1,6-diisocyanatohexane, 1,10-diisocyanatodecane,
1,3- and 1,4-diisocyanatocyclohexane,
1,4-diisocyanato-3,3,5-trimethylcyclohexane,
1,3-diisocyanato-2-methylcyclohexane,
1,3-diisocyanato-4-methylcyclohexane,
I-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane
(isophorone diisocyanate; IPDI),
1-isocyanato-1-methyl-4(3)-isocyanatomethylcyclohexane, 2,4'- and
4,4'-diisocyanatodicyclohexylmethane (HI2MDI), 1,3- and
1,4-bis(isocyanatomethyl)cyclohexane,
bis(isocyanatomethyl)norbornane (NBDI),
4,4'-diisocyanato-3,3'-dimethyldicyclohexylmethane,
4,4'-diisocyanato-3,3',5,5'-tetramethyldicyclohexylmethane,
4,4'-diisocyanato-1,1'-bi(cyclohexyl),
4,4'-diisocyanato-3,3'-dimethyl-1,1'-bi(cyclohexyl),
4,4'-diisocyanato-2,2',5,5'-tetramethyl-1,1'-bi(cyclohexyl),
1,8-diisocyanato-p-menthane, 1,3-diisocyanatoadamantane,
1,3-dimethyl-5,7-diisocyanatoadamantane, 1,3- and
1,4-bis(isocyanatomethyl)benzene (xylylene diisocyanate; XDI), 1,3-
and 1,4-bis(1-isocyanato-1-methylethyl)benzene (TMXDI) and
bis(4-(l-isocyanato-1-methylethyl)phenyl) carbonate, 2,4- and
2,6-diisocyanatotoluene (TDI), 2,4'- and
4,4'-diisocyanatodiphenylmethane (MDI), 1,5-diisocyanatonaphthalene
and any desired mixtures of such diisocyanates. Further
diisocyanates that are likewise suitable can additionally be found,
for example, in Justus Liebigs Annalen der Chemie, volume 562
(1949) p. 75-136.
[0071] In addition, it is also possible according to the invention
to use conventional prepolymers bearing aliphatic or aromatic
isocyanate end groups, for example polyether, polyester,
polycarbonate prepolymers bearing aliphatic or aromatic isocyanate
end groups, as mono- and polyisocyanates in the composition A).
[0072] Suitable monomeric monoisocyanates which can optionally be
used in the composition A) are, for example, n-butyl isocyanate,
n-amyl isocyanate, n-hexyl isocyanate, n-heptyl isocyanate, n-octyl
isocyanate, undecyl isocyanate, dodecyl isocyanate, tetradecyl
isocyanate, cetyl isocyanate, stearyl isocyanate, cyclopentyl
isocyanate, cyclohexyl isocyanate, 3- or 4-methylcyclohexyl
isocyanate or any desired mixtures of such monoisocyanates. An
example of a monomeric isocyanate having an isocyanate
functionality greater than two which can optionally be added to the
composition A) is 4-isocyanatomethyloctane 1,8-diisocyanate
(triisocyanatononane; TIN).
[0073] In one embodiment of the invention, the composition A)
contains not more than 30% by weight, especially not more than 20%
by weight, not more than 15% by weight, not more than 10% by
weight, not more than 5% by weight or not more than 1% by weight,
based in each case on the weight of the composition A), of aromatic
polyisocyanates. As used here, "aromatic polyisocyanate" means a
polyisocyanate having at least one aromatically bonded isocyanate
group.
[0074] Aromatically bonded isocyanate groups are understood to mean
isocyanate groups bonded to an aromatic hydrocarbyl radical.
[0075] In a preferred embodiment of the invention, a composition A)
having exclusively aliphatically and/or cycloaliphatically bonded
isocyanate groups is used.
[0076] Aliphatically and cycloaliphatically bonded isocyanate
groups are understood to mean isocyanate groups bonded,
respectively, to an aliphatic and cycloaliphatic hydrocarbyl
radical.
[0077] In another preferred embodiment of the invention, a
composition A) containing one or more oligomeric polyisocyanates B)
is used, wherein the one or more oligomeric polyisocyanates B)
comprise exclusively aliphatically and/or cycloaliphatically bonded
isocyanate groups.
[0078] Practical experiments have shown that particularly good
results can be achieved with compositions A) in which the
oligomeric polyisocyanates present therein comprise exclusively
aliphatically and/or cycloaliphatically bonded isocyanate
groups.
[0079] In a particularly preferred embodiment of the invention, a
composition A) is used which contains one or more oligomeric
polyisocyanates B), where the one or more oligomeric
polyisocyanates is/are based on 1,5-diisocyanatopentane, (PDI),
1,6-diisocyanatohexane (HDI), isophorone diisocyanate (IPDI) or
4,4'-diisocyanatodicyclohexylmethane (HI2MDI) or mixtures
thereof.
[0080] The oligomeric polyisocyanates B) employed in the
composition A) in the catalytic trimerization preferably have a low
viscosity. When reference is made here to "low viscosity" this
means that the oligomeric polyisocyanates B) have at room
temperature a viscosity below the gel point of the oligomeric
polyisocyanates B), i.e. the oligomeric polyisocyanates B) are in
the form of a liquid and not a gel. The gel point is understood to
mean the time at which the crosslinking density of the oligomeric
polyisocyanates B) has progressed to an extent such that the
viscosity of the oligomeric polyisocyanates B) abruptly increases
and the oligomeric polyisocyanates B) gel to afford a
polyisocyanurate bulk material, i.e. no longer undergo substantial
deformation or flow.
[0081] The oligomeric silicon-modified polyisocyanates D) are
typically obtained by oligomerization of simple aliphatic,
cycloaliphatic, araliphatic and/or aromatic monomeric diisocyanates
as previously described as starting diisocyanates for the
production of the oligomeric polyisocyanates B) in admixture with
silicon-modified diisocyanates and/or isocyanatoalkylsilanes or by
partial reaction of oligomeric polyisocyanates B) with
isocyanate-reactive silicon-containing compounds C). The terms
"partial reaction with silicon-containing compounds" and
"silicon-modified" are used interchangeably in the context of the
invention and mean in particular that I to 99.9, preferably 5 to
80, particularly preferably 10 to 50, very particularly preferably
15 to 40, mol % of the isocyanate groups originally present in the
oligomeric polyisocyanate or in the diisocyanate have been reacted
with silicon-containing compounds C). In other words the
oligomeric, silicon-modified polyisocyanates D) produced by partial
reaction of oligomeric polyisocyanates B) with silicon-containing
compounds C) have an isocyanate content of 99.0 to 0.1 mol %,
preferably 95 to 20 mol %, particularly preferably 90 to 50 mol %,
very particularly preferably 85 to 60 mol %, based on the
originally present isocyanate groups of the oligomeric
polyisocyanates B).
[0082] Production processes for the oligomeric, silicon-modified
polyisocyanates D) having uretdione, isocyanurate, allophanate,
biuret, iminooxadiazinedione and/or oxadiazinetrione structure to
be used according to the invention in the low-monomer composition
A) and obtainable by reaction of oligomeric polyisocyanates B) with
isocyanate-reactive silicon-containing compounds C) are described
for example in EP-A 1 273 640, WO-A 2008/074490, WO-A 2008/074489,
WO-A 2014/086530, WO-A 2010/149236, WO-A 2009/156148.
[0083] Further oligomeric, silicon-modified polyisocyanates D) also
include for example the allophanate-containing and
silane-containing polyisocyanates described in EP-A 2 014 692 and
EP-A 2 305 691 that are obtainable by reaction of silane-containing
hydroxyurethanes and/or hydroxyamides with excess amounts of
monomeric diisocyanates.
[0084] Further oligomeric, silicon-modified polyisocyanates D) also
include for example the alkoxysilane-functional biuret
polyisocyanates obtainable by reaction of amino silanes with HDI,
according to the process of WO 2005/070942.
[0085] Also usable according to the invention as oligomeric,
silicon-modified polyisocyanates D) in the low-monomer composition
A) are the silane-containing thioallophanate polyisocyanates
described in the present applicant's own as yet unpublished patent
application BMS 141043-EP (application No: 14 172 295.9).
[0086] Silicon-containing compounds C) that may be used include
organic and inorganic silicon-containing compounds C). "Inorganic
silicon-containing compounds" is understood to mean
silicon-containing compounds which do not comprise a silicon-carbon
bond. Inorganic silicon-containing compounds C) suitable according
to the invention are for example SiO.sub.2 nanoparticles or
organosols or silicates.
[0087] The silicon-containing compound C) need not comprise
isocyanate-reactive functional groups.
[0088] Silicon-containing compounds C) inert toward isocyanate
groups are for example reaction products of diisocyanates or
oligomeric polyisocyanates in which the originally present
isocyanate groups have been completely reacted with
isocyanate-reactive silicon-containing compounds C). Examples of
such silicon-containing compounds C) are for example the
isocyanate-free reaction products of monomeric diisocyanates and/or
oligomeric polyisocyanates with secondary aminosilanes described in
WO 2006/042584 and WO 2007/033786.
[0089] A further type of silicon-containing compound C) inert
toward isocyanate groups is also reaction products of
isocyanate-functional silane building blocks with at least
equimolar amounts of hydroxyl-functional and/or amino-functional
compounds. Examples of such silicon-containing compounds C) are for
example the reaction products of isocyanatoalkylalkoxysilanes with
diols or polyols described in WO 2008/034409 or WO 2013/189882 or
the reaction products of diols and/or polyols with specific
thiourethane-containing isocyanatosilanes described in WO
2014/037265.
[0090] However, in a preferred embodiment of the invention the
silicon-containing compounds C) have at least one
isocyanate-reactive functional group. This allows in situ
modification of the oligomeric polyisocyanates B) optionally
likewise present in the composition A), thus affording oligomeric
silicon-modified polyisocyanates D). Usable isocyanate-reactive
functional groups include in particular hydroxyl groups, thiol
groups, amino groups, amide groups and isocyanate groups.
[0091] It has proven of particular practical relevance to use
silicon-containing compounds C) selected from the group consisting
of aminosilanes E), silane-functional aspartic esters F),
silane-functional alkylamides G), mercaptosilanes H),
isocyanatosilanes I) and mixtures thereof. These each contain at
least one isocyanate-reactive functional group.
[0092] Suitable aminosilanes E) are for example
3-aminopropyltrimethoxysilane, 3-am inopropyltriethoxysilane,
3-aminopropylmethyldimethoxysilane,
3-aminopropylmethyldiethoxysilane,
3-aminopropylethyldiethoxysilane,
3-aminopropyldimethylethoxysilane,
3-aminopropyldiisopropylethoxysilane, 3-am
inopropyltripropoxysilane, 3-aminopropyltributoxysilane, 5
3-aminopropyiphenyldiethoxysilane,
3-aminopropylphenyldimethoxysilane,
3-aminopropyltris(methoxyethoxyethoxy)silane,
2-aminoisopropyltrimethoxysilane, 4-aminobutyltrimethoxysilane,
4-aminobutyltriethoxysilane, 4-aminobutylmethyldimethoxysilane,
4-aminobutylmethyldiethoxysilane, 4-aminobutylethyldimethoxysilane,
4-aminobutylethyldiethoxysilane, 4-aminobutyldimethylmethoxysilane,
4-aminobutylphenyldimethoxysilane, 4-am
inobutylphenyldiethoxysilane,
4-amino(3-methylbutyl)methyldimethoxysilane,
4-amino(3-methylbutyl)methyldiethoxysilane,
4-amino(3-methylbutyl)trimethoxysilane,
3-aminopropylphenylmethyl-n-propoxysilane,
3-aminopropylmethyldibutoxysilane,
3-aminopropyldiethylmethylsilane,
3-aminopropylmethylbis(trimethylsiloxy)silane,
11-aminoundecyltrimethoxysilane,
N-methyl-3-aminopropyltrimethoxysilane,
N-methyl-3-aminopropyltriethoxysilane,
N-(n-butyl)-3-aminopropyltrimethoxysilane,
N-(n-butyl)-3-aminopropyltriethoxysilane,
N-(2-aminoethyl)-3-aminopropyltrimethoxysilane,
N-(2-aminoethyl)-3-aminoisobutylmethyldimethoxysilane,
N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane,
N-(2-aminoethyl)-3-aminopropyltris(2-ethylhexoxy)silane,
N-(6-aminohexyl)-3-aminopropyltrimethoxysilane,
N-benzyl-N-(2-aminoethyl)-3-aminopropyltrimethoxysilane,
bis(3-trimethoxysilylpropyl)amine,
bis(3-triethoxysilylpropyl)amine,
(aminoethylaminomethyl)phenethyltrimethoxysilane,
N-vinylbenzyl-N-(2-aminoethyl)-3-aminopropylpolysiloxane,
N-vinylbenzyl-N(2-aminoethyl)-3-aminopropylpolysiloxane,
3-ureidopropyltriethoxysilane,
3-(m-aminophenoxy)propyltrimethoxysilane, m- and/or
p-aminophenyltrimethoxysilane,
3-(3-aminopropoxy)-3,3-dimethyl-1-propenyltrimethoxysilane,
3-aminopropylmethylbis(trimethylsiloxy)silane,
3-aminopropyltris(trimethylsiloxy)silane,
3-aminopropylpentamethyldisiloxane or any desired mixtures of such
aminosilanes.
[0093] Very particularly preferred aminosilanes E) are
N-methyl-3-aminopropyltrimethoxysilane,
N-methyl-3-aminopropyltriethoxysilane,
N-(n-Butyl)-3-aminopropyltrimethoxysilane,
N-(n-butyl)-3-aminopropyltriethoxysilane,
bis(3-trimethoxysilylpropyl)amine and/or
bis(3-triethoxysilylpropyl)amine.
[0094] Suitable silane-functional aspartic esters F) are obtainable
according to the teaching of EP-A 0 596 360 by reaction of
aminosilanes bearing primary amino groups with fumaric esters
and/or maleic esters.
[0095] Particularly preferred silane-functional aspartic esters F)
are reaction products of 3-aminopropyltrimethoxysilane and/or
3-aminopropyltriethoxysilane with diethyl maleate.
[0096] Silane-functional alkylamides G) suitable according to the
invention are obtainable, for example, by the processes disclosed
in U.S. Pat. Nos. 4,788,310 and 4,826,915 by reaction of
aminosilanes bearing primary amino groups with alkyl
alkylcarboxylates with elimination of alcohol.
[0097] Particularly preferred silane-functional alkylamides G) are
reaction products of 3-aminopropyltrimethoxysilane and/or
3-aminopropyltriethoxysilane with methyl formate and/or ethyl
formate.
[0098] Examples of mercaptosilanes H) suitable according to the
invention are for example 2-mercaptoethyltrimethylsilane,
2-mercaptoethylmethyldimethoxysilane,
2-mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane,
3-mercaptopropylmethyldimethoxysi lane,
3-mercaptopropyldimethylmethoxysilane,
3-mercaptopropyltrimethoxysilane,
3-mercaptopropylmethyldiethoxysilane,
3-mercaptopropyltriethoxysilane,
3-mercaptopropylethyldimethoxysilane,
3-mercaptopropylethyldiethoxysilane and/or
4-mercaptobutyltrimethoxysilane.
[0099] Very particularly preferred mercaptosilanes H) are in
particular 3-mercaptopropyltrimethoxysilane and/or
3-mercaptopropyltriethoxysilane.
[0100] Isocyanatosilanes I) suitable according to the invention are
for example 3-isocyanatopropyltrimethoxysilane,
3-isocyanatopropyltriethoxysilane,
3-isocyanatopropyltriisopropoxysilane,
2-isocyanatoethyltrimethoxysilane,
2-isocyanatoethyltriethoxysilane,
2-isocyanatoethyltriisopropoxysilane,
4-isocyanatobutyltrimethoxysilane,
4-isocyanatobutyltriethoxysilane,
4-isocyanatobutyltriisopropoxysilane,
isocyanatomethyltrimethoxysilane, isocyanatomethyltriethoxysilane,
isocyanatomethyltriisopropoxysilane or the low-monomer
isocyanatosilanes having thiourethane structure obtainable by the
process of WO 2014/037279.
[0101] Preferably used isocyanatosilanes I) are
3-isocyanatopropyltrimethoxysilane and/or
3-isocyanatopropyltriethoxysilane.
[0102] In a preferred embodiment of the invention, the
silicon-containing compounds C) and the oligomeric silicon-modified
polyisocyanates D) comprise at least one structural unit selected
from the group consisting of:
a) a structural unit of formula (I)
##STR00005## [0103] wherein [0104] R.sup.1, R.sup.2 and R.sup.3 are
identical or different radicals and are each a saturated or
unsaturated, linear or branched, aliphatic or cycloaliphatic or an
optionally substituted aromatic or araliphatic radical having 1 to
18 carbon atoms, which may optionally contain 1 to 3 heteroatoms
from the series of oxygen, sulfur and nitrogen, [0105] X is a
linear or branched organic radical which has at least 1 carbon atom
and may optionally contain 1 to 2 imino groups (--NH--), and [0106]
R.sup.4 is hydrogen, a saturated or unsaturated, linear or
branched, aliphatic or cycloaliphatic or an optionally substituted
aromatic or araliphatic radical having 1 to 18 carbon atoms or a
radical of the formula
[0106] ##STR00006## in which R.sup.1, R.sup.2, R.sup.3 and X are as
defined above; b) a structural unit of formula (II)
##STR00007## [0107] wherein R.sup.1, R.sup.2 and R.sup.3 are as
defined for formula (I), [0108] X is a linear or branched organic
radical having at least 1 carbon atom and [0109] R.sup.5 and
R.sup.6 are independently saturated or unsaturated, linear or
branched, aliphatic or cycloaliphatic or aromatic organic radicals
which have 1 to 18 carbon atoms, are substituted or unsubstituted
and/or have heteroatoms in the chain; c) a structural unit of
formula (III)
[0109] ##STR00008## [0110] wherein R.sup.1, R.sup.2 and R.sup.3 are
as defined for formula (I), [0111] X is a linear or branched
organic radical having at least 1 carbon atom and [0112] R.sup.9 is
a saturated linear or branched, aliphatic or cycloaliphatic organic
radical having 1 to 8 carbon atoms; d) a structural unit of formula
(IV)
[0112] ##STR00009## [0113] wherein R.sup.1, R.sup.2 and R.sup.3 are
as defined for formula (I) [0114] and [0115] Y is a linear or
branched organic radical having at least 1 carbon atom; [0116] and
e) a structural unit of formula (V)
[0116] ##STR00010## [0117] wherein R.sup.1, R.sup.2 and R.sup.3 are
as defined for formula (I), [0118] and [0119] Y is a linear or
branched organic radical having at least 1 carbon atom.
[0120] In a further preferred embodiment of the invention, the
silicon-containing compounds C) and the oligomeric silicon-modified
polyisocyanates D) comprise at least one structural unit selected
from the group consisting of:
a) a structural unit of formula (I)
##STR00011## [0121] wherein [0122] R.sup.1, R.sup.2 and R.sup.3 are
each methyl, methoxy and/or ethoxy, with the proviso that at least
one of the radicals R.sup.1, R.sup.2 and R.sup.3 is such a methoxy
or ethoxy radical, [0123] X is a propylene radical
(--CH.sub.2--CH.sub.2--CH.sub.2--), and [0124] R.sup.4 is hydrogen,
a methyl radical or a radical of formula
[0124] ##STR00012## in which R.sup.1, R.sup.2, R.sup.3 and X are as
defined above; b) a structural unit of formula (II)
##STR00013## [0125] wherein [0126] R.sup.1, R.sup.2, R.sup.3 and X
wherein R.sup.1, R.sup.2 and R.sup.3 are as defined for formula
(I), [0127] R.sup.5 and R.sup.6 are identical or different radicals
and are a methyl-, ethyl-, n-butyl- or 2-ethylhexyl radical; c) a
structural unit of formula (III)
[0127] ##STR00014## [0128] wherein [0129] R.sup.1, R.sup.2, R.sup.3
and X wherein R.sup.1, R.sup.2 and R.sup.3 are as defined for
formula (I), [0130] R.sup.9 is hydrogen; d) a structural unit of
formula (IV)
[0130] ##STR00015## [0131] wherein [0132] R.sup.1, R.sup.2 and
R.sup.3 wherein R.sup.1, R.sup.2 and R.sup.3 are as defined for
formula (I), Y is a propylene radical
(--CH.sub.2--CH.sub.2--CH.sub.2--); and e) a structural unit of
formula (V)
[0132] ##STR00016## [0133] wherein R.sup.1, R.sup.2 and R.sup.3 are
as defined for formula (I), [0134] and [0135] Y is a linear or
branched organic radical having at least 1 carbon atom.
[0136] The polyisocyanurates of the invention are obtainable by
catalytic trimerization by the process of the invention.
"Catalytic" here means in the presence of a suitable trimerization
catalyst L).
[0137] To accelerate the hydrolysis and condensation of the
alkoxysilane groups it is also possible to use further catalysts in
addition to the trimerization catalysts provided that said further
catalysts do not significantly retard or even inhibit the
trimerization reaction. Catalysts of this kind are for example
bases, for example N-substituted amidines such as
1,5-diazabicyclo[4.3.0]non-5-ene (DBN) and
1,5-diazabicyclo[5.4.0]undec-7-ene (DBU), but also metal salts or
organometallic compounds, such as tetraisopropyl titanate,
tetrabutyl titanate, titanium(IV) acetylacetonate, aluminum
acetylacetonate, aluminum triflate or tin triflate, for
example.
[0138] Suitable trimerization catalysts L) for the process
according to the invention are in principle any compounds which
accelerate the trimerization of isocyanate groups to isocyanurate
structures. It is preferable to use a trimerization catalyst L)
which does not accelerate or does not significantly accelerate the
trimerization reaction below 25.degree. C., in particular below
30.degree. C., preferably below 40.degree. C., but significantly
accelerates said reaction above 60.degree. C., in particular above
70.degree. C. "Does not significantly accelerate" here means that
below 25.degree. C., in particular below 30.degree. C., preferably
below 40.degree. C., the presence of the trimerization catalyst L)
in the reaction mixture does not have any significant effect on the
reaction rate of the reaction that proceeds in any case. A
significant acceleration is understood to mean that above
60.degree. C., in particular above 70.degree. C., the presence of
the thermally latent catalyst in the reaction mixture has a
distinct effect on the reaction rate of the reaction that proceeds
in any case.
[0139] Since isocyanurate formation, depending-on the catalyst
used, is frequently accompanied by side reactions, for example
dimerization to give uretdione structures or trimerization to form
iminooxadiazinediones (called asymmetric trimers), and by
allophanatization reactions in the case of presence of urethane
groups in the starting polyisocyanate, the term "trimerization"
shall also synonymously represent these reactions that proceed
additionally in the context of the present invention.
[0140] In a particular embodiment, however, trimerization means
that predominantly cyclotrimerizations of at least 50%, preferably
at least 60%, particularly preferably at least 70%, in particular
at least 80%, of the isocyanate groups present in the composition
A) to give isocyanurate structural units are catalyzed. However,
side reactions, especially those to give uretdione, allophanate
and/or iminooxadiazinedione structures, typically occur and can
even be used in a controlled manner in order to advantageously
affect, for example, the Tg value of the polyisocyanurate plastic
obtained.
[0141] Suitable catalysts L) for the process according to the
invention are, for example, simple tertiary amines, for example
triethylamine, tributylamine, N,N-dimethylaniline,
N-ethylpiperidine or N,N'-dimethylpiperazine. Suitable catalysts
are also the tertiary hydroxyalkylamines described in GB 2 221 465,
for example triethanolamine, N-methyldiethanolamine,
dimethylethanolamine, N-isopropyldiethanolamine and
1-(2-hydroxyethyl)pyrrolidine, or the catalyst systems that are
known from GB 2 222 161 and consist of mixtures of tertiary
bicyclic amines, for example DBU, with simple low molecular weight
aliphatic alcohols.
[0142] Likewise suitable as trimerization catalysts L) for the
process of the invention are a multitude of different metal
compounds. Suitable examples are the octoates and naphthenates of
manganese, iron, cobalt, nickel, copper, zinc, zirconium, cerium or
lead that are described as catalysts in DE-A 3 240 613, or mixtures
thereof with acetates of lithium, sodium, potassium, calcium or
barium, the sodium and potassium salts of linear or branched
alkanecarboxylic acids having up to 10 carbon atoms that are known
from DE-A 3 219 608, for example of propionic acid, butyric acid,
valeric acid, caproic acid, heptanoic acid, caprylic acid,
pelargonic acid, capric acid and undecylic acid, the alkali metal
or alkaline earth metal salts of aliphatic, cycloaliphatic or
aromatic mono- and polycarboxylic acids having 2 to 20 carbon atoms
that are known from EP-A 0 100 129, for example sodium or potassium
benzoate, the alkali metal phenoxides known from GB-A 1 391 066 and
GB-A 1 386 399, for example sodium or potassium phenoxide, the
alkali metal and alkaline earth metal oxides, hydroxides,
carbonates, aikoxides and phenoxides known from GB 809 809, alkali
metal salts of enolizable compounds and metal salts of weak
aliphatic or cycloaliphatic carboxylic acids, for example sodium
methoxide, sodium acetate, potassium acetate, sodium acetoacetate,
lead 2-ethylhexanoate and lead naphthenate, the basic alkali metal
compounds complexed with crown ethers or polyether alcohols that
are known from EP-A 0 056 158 and EP-A 0 056 159, for example
complexed sodium or potassium carboxylates, the
pyrrolidinone-potassium salt known from EP-A 0 033 581, the mono-
or polynuclear complexs of titanium, zirconium and/or hafnium known
from application EP 13196508.9, for example zirconium tetra-n
butoxide, zirconium tetra-2-ethylhexanoate and zirconium
tetra-2-ethylhexoxide, and tin compounds of the type described in
European Polymer Journal, vol. 16, 147-148 (1979), for example
dibutyltin dichloride, diphenyltin dichloride, triphenylstannanol,
tributyltin acetate, tributyltin oxide, tin octoate,
dibutyl(dimethoxy)stannane and tributyltin imidazolate.
[0143] Further trimerization catalysts L) suitable for the process
according to the invention are, for example, the quaternary
ammonium hydroxides known from DE-A 1 667 309, EP-A 0 013 880 and
EP-A 0 047 452, for example tetraethylammonium hydroxide,
trimethylbenzylammonium hydroxide,
N,N-dimethyl-N-dodecyl-N-(2-hydroxyethyl)ammonium hydroxide,
N-(2-hydroxyethyl)-N,N-dimethyl-N-(2,2'-dihydroxymethylbutyl)ammonium
hydroxide and 1-(2-hydroxyethyl)-1,4-diazabicyclo[2.2.2]octane
hydroxide (monoadduct of ethylene oxide and water with
1,4-diazabicyclo[2.2.2]octane), the quaternary hydroxyalkylammonium
hydroxides known from EP-A 37 65 or EP-A 10 589, for example
N,N,N-trimethyl-N-(2-hydroxyethyl)ammonium hydroxide, the
trialkylhydroxylalkylammonium carboxylates that are known from DE-A
2631733, EP-A 0 671 426, EP-A 1 599 526 and U.S. Pat. No.
4,789,705, for example N,N,N-trimethyl-N-2-hydroxypropylammonium
p-tert-butylbenzoate and N,N,N-trimethyl-N-2-hydroxypropylammonium
2-ethylhexanoate, the quaternary benzylammonium carboxylates known
from EP-A 1 229 016, such as N-benzyl-N,N-dimethyl-N-ethylammonium
pivalate, N-benzyl-N,N-dimethyl-N-ethylammonium 2-ethylhexanoate,
N-benzyl-N,N,N-tributylammonium 2-ethylhexanoate,
N,N-dimethyl-N-ethyl-N-(4-methoxybenzyl)ammonium 2-ethylhexanoate
or N,N,N-tributyl-N-(4-methoxybenzyl)ammonium pivalate, the
tetrasubstituted ammonium a-hydroxycarboxylates known from WO
2005/087828, for example tetramethylammonium lactate, the
quaternary ammonium or phosphonium fluorides known from EP-A 0 339
396, EP-A 0 379 914 and EP-A 0 443 167, for example
N-methyl-N,N,N-trialkylammonium fluorides with
C.sub.8-C.sub.10-alkyl radicals, N,N,N,N-tetra-n-butylammonium
fluoride, N,N,N-trimetbyl-N-benzylammonium fluoride,
tetramethylphosphonium fluoride, tetraethylphosphonium fluoride or
tetra-n-butylphosphonium fluoride, the quaternary ammonium and
phosphonium polyfluorides known from EP-A 0 798 299, EP-A 0 896 009
and EP-A 0 962 455, for example benzyltrimethylammonium hydrogen
polyfluoride, the tetraalkylammonium alkylcarbonates obtainable by
reaction of tertiary amines with dialkyl carbonates, or
betaine-structured quaternary ammonioalkyl carbonates, which are
known from EP-A 0 668 271, the quaternary ammonium
hydrogencarbonates known from WO 1999/023128, such as choline
bicarbonate, the quaternary ammonium salts which are known from EP
0 102 482 and are obtainable from tertiary amines and alkylating
esters of phosphorus acids, examples of such salts being reaction
products of triethylamine, DABCO or N-methylmorpholine with
dimethyl methanephosphonate, or the tetrasubstituted ammonium salts
of lactams that are known from WO 2013/167404, for example
trioctylammonium caprolactamate or dodecyltrimethylammonium
caprolactamate.
[0144] Further trimerization catalysts L) suitable for the process
of the invention can be found, for example, in J. H. Saunders and
K. C. Frisch, Polyurethanes Chemistry and Technology, p. 94 ff.
(1962) and the literature cited therein.
[0145] The catalysts L) can be used in the process of the invention
either individually or in the form of any desired mixtures with one
another.
[0146] Preferred catalysts L) are metal compounds of the
aforementioned type, especially carboxylates and alkoxides of
alkali metals, alkaline earth metals or zirconium, and organic tin
compounds of the type mentioned.
[0147] Particularly preferred trimerization catalysts L) are sodium
and potassium salts of aliphatic carboxylic acids having 2 to 20
carbon atoms and aliphatically substituted tin compounds.
[0148] Very particularly preferred trimerization catalysts L) for
the process according to the invention are potassium acetate, tin
octoate and/or tributyltin oxide.
[0149] In one embodiment of the invention catalytic trimerization
is carried out in the presence of a trimerization catalyst L),
wherein the trimerization catalyst L) preferably comprises at least
one alkali metal or alkaline earth metal salt.
[0150] In a preferred embodiment of the invention the trimerization
catalyst L) comprises potassium acetate as the alkali metal salt
and/or a polyether, in particular a polyethylene glycol.
[0151] In the process according to the invention, the trimerization
catalyst L) is generally used in a concentration based on the
amount of the composition A) used of 0.0005% to 5.0% by weight,
preferably of 0.10% to 2.0% by weight and particularly preferably
of 0.25% to 1.0% by weight.
[0152] The trimerization catalysts L) that are used in the process
of the invention generally have sufficient solubility in the
composition A) in the amounts that are required for initiation of
the oligomerization reaction. The catalyst L) is therefore
preferably added to the composition A) in neat form.
[0153] Optionally, however, the catalysts L) can also be used
dissolved in a suitable organic solvent to improve their
incorporability. The dilution level of the catalyst solutions can
be chosen freely within a very wide range. Such catalyst solutions
are typically catalytically active from a concentration of about
0.01% by weight based on the total weight of catalyst and of the
organic solvent.
[0154] Suitable catalyst solvents are, for example, solvents that
are inert toward isocyanate groups, for example hexane, toluene,
xylene, chlorobenzene, ethyl acetate, butyl acetate, diethylene
glycol dimethyl ether, dipropylene glycol dimethyl ether, ethylene
glycol monomethyl or monoethyl ether acetate, diethylene glycol
ethyl and butyl ether acetate, propylene glycol monomethyl ether
acetate, I-methoxyprop-2-yl acetate, 3-methoxy-n-butyl acetate,
propylene glycol diacetate, acetone, methyl ethyl ketone, methyl
isobutyl ketone, cyclohexanone, lactones such as P-propiolactone,
y-butyrolactone, .epsilon.-caprolactone and
.epsilon.-methylcaprolactone, but also solvents such as
N-methylpyrrolidone and N-methylcaprolactam, 1,2-propylene
carbonate, methylene chloride, dimethyl sulfoxide, triethyl
phosphate or any desired mixtures of such solvents.
[0155] If catalyst solvents are used in the process of the
invention, preference is given to using catalyst solvents which
bear groups reactive toward isocyanates and can be incorporated
into the polyisocyanurate plastic. Examples of such solvents are
mono- or polyhydric simple alcohols, for example methanol, ethanol,
n-propanol, isopropanol, n-butanol, n-hexanol, 2-ethyl-1-hexanol,
ethylene glycol, propylene glycol, the isomeric butanediols,
2-ethylhexane-1,3-diol or glycerol; ether alcohols, for example
1-methoxy-2-propanol, 3-ethyl-3-hydroxymethyloxetane,
tetrahydrofurfuryl alcohol, ethylene glycol monomethyl ether,
ethylene glycol monoethyl ether, ethylene glycol monobutyl ether,
diethylene glycol monomethyl ether, diethylene glycol monoethyl
ether, diethylene glycol monobutyl ether, diethylene glycol,
dipropylene glycol or else liquid higher molecular weight
polyethylene glycols, polypropylene glycols, mixed
polyethylene/polypropylene glycols and the monoalkyl ethers
thereof; ester alcohols, for example ethylene glycol monoacetate,
propylene glycol monolaurate, glycerol mono- and diacetate,
glycerol monobutyrate or 2,2,4-trimethylpentane-1,3-diol
monoisobutyrate; unsaturated alcohols, for example allyl alcohol,
1,1-dimethylallyl alcohol or oleyl alcohol; araliphatic alcohols,
for example benzyl alcohol; N-monosubstituted amides, for example
N-methylformamide, N-methylacetamide, cyanoacetamide or
2-pyrrolidinone, or any desired mixtures of such solvents.
[0156] The polyisocyanurate plastics obtainable by the process of
the invention, even as such, i.e. without addition of appropriate
auxiliaries and additives M), feature very good light stability.
Nevertheless, it is optionally also possible to use in the
production of said plastics standard auxiliaries and additives M),
for example standard fillers, UV stabilizers, antioxidants, mold
release agents, water scavengers, slip additives, defoamers,
levelling agents, rheology additives, flame retardants and/or
pigments. These auxiliaries and additives M), excluding fillers and
flame retardants, are typically present in the polyisocyanurate
plastic in an amount of less than 10% by weight, preferably less
than 5% by weight, particularly preferably up to 3% by weight,
based on the composition A). Flame retardants are typically present
in the polyisocyanurate plastic in amounts of not more than 70% by
weight, preferably not more than 50% by weight, particularly
preferably not more than 30% by weight, calculated as the total
amount of employed flame retardants, based on the total weight of
the composition A).
[0157] Suitable fillers M.sub.w) are, for example AlOH.sub.3,
CaCO.sub.3, metal pigments such as TiO.sub.2 and further known
standard fillers. These fillers M.sub.w) are preferably used in
amounts of not more than 70% by weight, preferably not more than
50% by weight, particularly preferably not more than 30% by weight,
calculated as the total amount of employed fillers based on the
total weight of the composition A).
[0158] Suitable UV stabilizers M.sub.x) may preferably be selected
from the group consisting of piperidine derivatives, for example
4-benzoyloxy-2,2,6,6-tetramethylpiperidine,
4-benzoyloxy-1,2,2,6,6-pentamethylpiperidine,
bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate,
bis(1,2,2,6,6-pentamethyl-1-4-piperidinyl) sebacate,
bis(2,2,6,6-tetramethyl-4-piperidyl) suberate,
bis(2,2,6,6-tetramethyl-4-piperidyl) dodecanedioate; benzophenone
derivatives, for example 2,4-dihydroxy-, 2-hydroxy-4-methoxy-,
2-hydroxy-4-octoxy-, 2-hydroxy-4-dodecyloxy- or
2,2'-dihydroxy-4-dodecyloxybenzophenone; benzotriazole derivatives,
for example 2-(2H-benzotriazol-2-yl)-4,6-di-tert-pentylphenol,
2-(2H-benzotriazol-2-yl)-6-dodecyl-4-methylphenol,
2-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1-phenylethyl)phenol,
2-(5-chloro-2H-benzotriazol-2-yl)-6-(1,1-dimethylethyl)-4-methylphenol,
2-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol,
2-(2H-benzotriazol-2-yl)-6-(I-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethy-
lbutyl)phenol, isooctyl
3-(3-(2H-benzotriazol-2-yl)-5-(1,1-dimethylethyl)-4-hydroxyphenylpropiona-
te), 2-(2H-benzotriazol-2-yl)-4,6-bis(1,1-dimethylethyl)phenol,
2-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1-phenylethyl)phenol,
2-(5-chloro-2H-benzotriazol-2-yl)-4,6-bis(1,1-dimethylethyl)phenol;
oxalanilides, for example 2-ethyl-2'-ethoxy- or
4-methyl-4'-methoxyoxalanilide; salicylic esters, for example
phenyl salicylate, 4-tert-butylphenyl salicylate,
4-tert-octylphenyl salicylate; cinnamic ester derivatives, for
example methyl a-cyano-.beta.-methyl-4-methoxycinnamate, butyl
a-cyano-.beta.-methyl-4-methoxycinnamate, ethyl
a-cyano-.beta.-phenylcinnamate, isooctyl
a-cyano-.beta.-phenylcinnamate; and malonic ester derivatives, such
as dimethyl 4-methoxybenzylidenemalonate, diethyl
4-methoxybenzylidenemalonate, dimethyl 4 butoxybenzylidenemalonate.
These preferred light stabilizers can be used either individually
or in any desired combinations with one another.
[0159] Particularly preferred UV stabilizers M.sub.x) for the
polyisocyanurate plastics producible according to the invention are
those which fully absorb radiation of wavelength <400 nm. These
include the recited benzotriazole derivatives for example. Very
particularly preferred UV stabilizers are
2-(5-chloro-2H-benzotriazol-2-yl)-6-(1,1-dimethylethyl)-4-methylphenol,
2-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol and/or
2-(5-chloro-2H-benzotriazol-2-yl)-4,6-bis(1,1-dimethylethyl)phenol.
[0160] One or more of the UV stabilizers M.sub.x) recited by way of
example are optionally added to the composition A) preferably in
amounts of 0.001 to 3.0 wt %, particularly preferably 0.01 to 2 wt
%, calculated as the total amount of UV stabilizers used, based on
the total weight of the composition A).
[0161] Suitable antioxidants M.sub.y) are preferably sterically
hindered phenols, which may be selected preferably from the group
consisting of 2,6-di-tert-butyl-4-methylphenol (ionol),
pentaerythritol
tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate),
octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate,
triethylene glycol
bis(3-tert-butyl-4-hydroxy-5-methylphenyl)propionate, 2,2'-thio
bis(4-methyl-6-tert-butylphenol) and 2,2'-thiodiethyl
bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]. These may be
used either individually or in any desired combinations with one
another as required.
[0162] These antioxidants M.sub.y) are preferably used in amounts
of 0.01% to 3.0% by weight, particularly preferably 0.02% to 2.0%
by weight, calculated as the total amount of antioxidants used,
based on the total weight of the composition A).
[0163] Apart from the small amounts of any catalyst solvents to be
used, the process according to the invention may be performed in a
solvent-free manner. Especially in the case of the inventive use
for production of coatings or films, the polyisocyanate component
can optionally also be diluted with organic solvents to reduce the
processing viscosity. Solvents suitable for this purpose are, for
example, the catalyst solvents inert toward isocyanate groups that
have already been described above.
[0164] In the case of the inventive use for production of films,
semifinished products or moldings it is finally also possible to
add internal mold release agents M.sub.z) as further auxiliaries
and additives M).
[0165] These are preferably the nonionic surfactants that contain
perfluoroalkyl or polysiloxane units and are known as mold release
agents, quaternary alkyl ammonium salts, for example
trimethylethylammonium chloride, trimethylstearylammonium chloride,
dimethylethylcetylammonium chloride, triethyldodecylammonium
chloride, trioctylmethylammonium chloride and
diethylcyclohexyldodecylammonium chloride, acidic mono- and dialkyl
phosphates having 2 to 18 carbon atoms in the alkyl radical, for
example ethyl phosphate, diethyl phosphate, isopropyl phosphate,
diisopropyl phosphate, butyl phosphate, dibutyl phosphate, octyl
phosphate, dioctyl phosphate, isodecyl phosphate, diisodecyl
phosphate, dodecyl phosphate, didodecyl phosphate, tridecanol
phosphate, bis(tridecanol) phosphate, stearyl phosphate, distearyl
phosphate, and any desired mixtures of such mold release
agents.
[0166] Particularly preferred mold release agents M.sub.z) are the
acidic mono- and dialkyl phosphates mentioned, very particularly
preferably those having 8 to 12 carbon atoms in the alkyl
radical.
[0167] Internal mold release agents M.sub.z) are optionally used in
the process according to the invention preferably in amounts of
0.01% to 3.0% by weight, particularly preferably 0.02% to 2.0% by
weight, calculated as the total amount of internal mold release
agent used, based on the total weight of the composition A).
[0168] In one embodiment of the process according to the invention,
a trimerization catalyst L) or a mixture of different trimerization
catalysts L) is added to the composition A) described, optionally
under inert gas, for example nitrogen, and optionally with use of
the aforementioned solvents and auxiliaries and additives M), and
mixed in homogeneously with the aid of a suitable mixing unit. The
addition of catalyst L) and any solvent and auxiliaries and
additives M) to be used can be carried out in any sequence,
successively or in a mixture, in the above-specified amounts and
generally at a temperature of 0 to 100.degree. C., preferably of 15
to 80.degree. C., particularly preferably of 20 to 60.degree.
C.
[0169] The hereindescribed inventive polyisocyanurate plastic
containing siloxane groups is suitable for producing coatings,
films, semifinished products and moldings. Depending on the
intended use the application of the reaction mixture may be carried
out by different methods known per se.
[0170] For production of films or coatings, for example lacquers, a
reaction mixture comprising catalyst L) and composition A) can be
applied, for example by spraying, spreading, dipping, flow-coating,
printing or with the aid of brushes, rollers or doctor blades, in
one or more layers to any desired substrates, for example metal,
wood, glass, stone, ceramic materials, concrete, hard and flexible
plastics, textiles, leather and paper, which may optionally also be
provided with standard primers prior to the coating.
[0171] The invention also provides a substrate coated with a
coating containing the inventive polyisocyanurate plastic
containing siloxane groups, wherein the substrate may in particular
be selected from a vehicle body, in particular a goods vehicle or
motor vehicle body, and electronic entertainment devices, such as
laptops, tablets or mobile phones. The coating of the substrate
with the coating containing the polyisocyanurate plastic according
to the invention may be carried out by the abovementioned methods
known per se. Either a reaction mixture comprising catalyst L) and
composition A) may be applied to the substrate or a separate
application of the catalyst L) and of the composition A) onto the
substrate may be carried out.
[0172] The catalytic trimerization of the composition A) may in the
former case be started either already before application onto the
substrate by heating of the reaction mixture at temperatures as
defined hereinbelow or by heating, for example, the substrate after
application of the reaction mixture at temperatures as defined
hereinbelow. The reaction mixture may also be applied to a
substrate already heated before application at temperatures as
defined hereinbelow.
[0173] For production of solid bodies, for example semifinished
products or moldings, the mixture of catalyst L) and composition A)
can be introduced into open or closed molds, for example, by simple
manual pouring, or with the aid of suitable machinery, for example
the low-pressure or high-pressure machinery which is standard in
polyurethane technology.
[0174] Subsequently, the trimerization reaction can be started by
heating the coated substrates or filled molds for example, wherein
depending on the trimerization catalyst L) chosen in each case the
optimum reaction temperature is from 45.degree. C. to 200.degree.
C., particularly preferably from 60.degree. C. to 150.degree. C.,
very particularly preferably from 80.degree. C. to 140.degree. C.
The reaction temperature can be kept constant within the range
specified over the entire curing process to give the
polyisocyanurate, or else can be heated, for example, in a linear
or stepwise manner up to a temperature greater than 80.degree. C.,
preferably greater than 100.degree. C., for example up to
130.degree. C., over several hours. Where reference is made here to
"reaction temperature", this means the ambient temperature.
[0175] Depending on the catalyst L) chosen and the reaction
temperature chosen, the trimerization reaction is very
substantially complete, as defined hereinbelow, after a period of
less than one minute up to several hours or only after a number of
days. The progress of the reaction can initially still be monitored
by titrimetric determination of the NCO content, but gelation and
solidification of the reaction mixture sets in rapidly as the
reaction progresses, which makes wet-chemical analysis methods
impossible. The further conversion of isocyanate groups can then be
monitored only by spectroscopic methods, for example by IR
spectroscopy with reference to the intensity of the isocyanate band
at about 2270 cm.sup.-1.
[0176] The inventive polyisocyanurate plastics containing siloxane
groups are preferably highly converted siloxane-containing
polyisocyanurates, i.e. those in which the trimerization reaction
to give polyisocyanurate structures is very substantially complete.
A trimerization reaction to give polyisocyanurate structures can be
regarded as "very substantially complete" in the context of the
present invention when at least 80%, preferably at least 90%,
particularly preferably at least 95%, of the free isocyanate groups
originally present in the composition A) have reacted. In other
words only not more than 20%, not more than 10%, particularly
preferably not more than 5%, of the isocyanate groups originally
contained in the composition A) preferably remain present in the
siloxane-containing polyisocyanurate plastic according to the
invention. This can be achieved when in the process according to
the invention the catalytic trimerization is continued at least up
to a degree of conversion at which only, for example, not more than
20% of the isocyanate groups originally contained in the
composition A) remain present, so that a highly converted
polyisocyanurate is obtained.
[0177] The percentage of isocyanate groups still present can be
determined by comparison of the content of isocyanate groups in %
by weight in the original composition A) with the content of
isocyanate groups in % by weight in the reaction product, for
example by the aforementioned comparison of the intensity of the
isocyanate band at about 2270 cm.sup.-1 by means of IR
spectroscopy.
[0178] In the inventive polyisocyanurate plastics containing
siloxane groups the content of silicon (calculated from the value
for silicon dioxide determined gravimetrically after oxidative
digestion) based on the polyisocyanurate plastic is from 0.2% to
45%, preferably 1.0% to 25%, in particular from 4% to 15%.
[0179] Results of particular practical relevance are achievable
when the polyisocyanurate plastic containing siloxane groups is one
which comprises alkoxysiloxane groups. Such an
alkoxysiloxane-containing polyisocyanurate plastic is obtainable by
the process according to the invention, wherein the
silicon-containing compounds C) are alkoxysilyl-containing
compounds C) and the oligomeric silicon-modified polyisocyanates D)
are oligomeric polyisocyanates D) modified with alkoxysilyl
groups.
[0180] The process of the invention affords transparent,
yellowing-resistant, siloxane-containing polyisocyanurate plastics
which, depending on the nature of the starting polyisocyanate used,
not only contain isocyanurate structures and siloxane groups but
may also contain further oligomeric structures, such as uretdione,
allophanate, biuret, iminooxadiazinedione and/or oxadiazinetrione
structures and feature outstanding heat resistances.
[0181] The process according to the invention makes it possible to
synthesize highly converted siloxane-containing polyisocyanurate
plastics having different properties, for example different
hardnesses, mechanical properties or glass transition temperatures
in simple fashion by suitable selection of oligomeric
polyisocyanates B) and silicon-containing compounds C) and/or
oligomeric, silicon-modified polyisocyanates D).
[0182] In contrast to siloxane-containing polyurethane plastics
produced by urethanization of the isocyanate groups and
hydrolysis/condensation of the silicon-containing functional
groups, the inventive siloxane-containing polyisocyanurates feature
a significantly higher crosslinking density as a result of which
they are suitable in particular for manufacturing coatings having
high scratch resistance and chemicals resistance precision. The
comparatively low heat of reaction liberated also allows for
problem-free production of solid, large-volume moldings.
[0183] The invention is elucidated in greater detail hereinafter
with reference to examples.
EXAMPLES
1. Methods
[0184] All reported percentages are based on weight unless
otherwise stated.
[0185] The NCO contents were determined by titrimetry to DIN EN ISO
11909.
[0186] OH numbers were determined by titrimetry to DIN 53240-2:
2007-11, acid numbers to DIN 3682 5. The OH contents reported were
calculated from the OH numbers determined by analysis.
[0187] The residual monomer contents were measured in accordance
with DIN EN ISO 10283 by gas chromatography with an internal
standard.
[0188] All viscosity measurements were taken with a Physica MCR 51
rheometer from Anton Paar Germany GmbH (DE) according to DIN EN ISO
3219/A3.
[0189] Pendulum damping: Pendulum damping is measured to DIN EN ISO
1522 on a glass plate and is determined according to Konig.
[0190] Solvent resistance: For this purpose, a small amount of the
relevant solvents (xylene, 1-methoxyprop-2-yl acetate, ethyl
acetate or acetone) was added to a test tube and provided with a
cotton pad at the opening, so that an atmosphere saturated with
solvent was formed inside the test tube. The test tubes were
subsequently placed with the cotton pad on the lacquer surface
where they remained for 5 minutes. Once the solvent had been wiped
off, the film was examined for destruction/softening/loss of
adhesion (0=no change, 5=film destroyed).
[0191] Hammer test with steel wool (dry scratching):
[0192] A hammer (weight: 800 g without handle) covered with 00
steel wool on its flat side was cautiously placed onto the coated
surface at right angles and guided over the coating in a trace
without tipping and without additional physical force. 50
back-and-forth strokes were conducted in each case. After being
subjected to the scratching medium, the test surface was cleaned
with a soft cloth and subsequently the haze in comparison to the
value before the scratching was determined according to ASTM D1003
with a BYK-Gardner Haze Gard Plus instrument.
2. Materials
Example 1
[0193] Production of a Polyisocyanate Having Alkoxysilyl
Groups:
[0194] In a flask fitted with a thermometer, KPG stirrer, reflux
cooler and dropping funnel 536.2 g of Desmodur.RTM. N 3900
[Covestro AG, D, low-monomer polyisocyanurate polyisocyanate based
on hexamethylene diisocyanate (HDI), NCO content: 23.5%; viscosity
(23.degree. C.): 750 mPas, content of monomeric HDI.ltoreq.0.25%]
and 91 mg of zinc trifluoromethanesulfonate were initially charged
under a nitrogen atmosphere and heated to 100.degree. C. At this
temperature, over the course of 1 h, 373.1 g of
N-(3-trimethoxysilylpropyl)formamide (1.8 mol, prepared as per
example 1 of WO 2015/113919 A1) were added dropwise. Stirring was
continued at 100.degree. C. for a further 3 hours until the free
NCO group content had dropped to 4.8%. The batch was admixed with
114 g of butyl acetate and 114 g of solvent naphtha 100 and cooled
to room temperature.
[0195] A clear solution was obtained.
[0196] NCO content 4.4%
[0197] Si content: 4.4%
[0198] Solids content 80%
[0199] Viscosity (23.degree. C., shear gradient D=250 l/s) 1030
mPas.
Example 2
[0200] Production of a Polyisocyanate Having Alkoxysilyl Groups
[0201] Based on a working example in WO 2012/168079 (curing agent
system VB2-1), by reaction of 100 parts by weight of Desmodur N
3300 (low-monomer polyisocyanurate polyisocyanate based on HDI, NCO
content: 21.6%; average NCO functionality: 3.5; viscosity
(23.degree. C.): 3200 mPas, content of monomeric HDI.ltoreq.0.25%)
with a mixture of 30 parts by weight of
bis-[3-(trimethoxysilyl)propyl]amine and 21 parts by weight of
N-[3-(trimethoxysilyl)propyl]butylamine in 84 parts by weight of
butyl acetate at 50.degree. C., a partially silanized HDI
trimerizate was produced. After a reaction time of approximately
four hours, the characteristics found for the present solution were
as follows:
[0202] NCO content: 6.0%
[0203] Si content: 3.2%
[0204] Solids content: 64%
[0205] Viscosity (23.degree. C., shear gradient D=100 l/s): 70
mPas.
Example 3
[0206] Mixing of an Alkoxysilyl-Functional Diurethane with a
Polyisocyanate
[0207] 100 g of VESTANAT.RTM. EP-M 95 [Evonik Industries, DE;
solvent-free, trimethoxysilyl-containing crosslinker, produced
according to the teaching of WO 2014/180623 (table 1) by reaction
of 2 mol of 3-isocyanatopropyltrimethoxysilane with 1 mol of
1,9-nonanediol] were mixed with 200 g of Desmodur.RTM. N 3600
[Covestro AG, DE, low-monomer polyisocyanurate polyisocyanate based
on hexamethylene diisocyanate (HDI), NCO content: 23.0%; viscosity
(23.degree. C.): 1200 mPas, content of monomeric HDI .quadrature.
0.25%] with exclusion of moisture at room temperature.
[0208] NCO content: 15.3%
[0209] Si content: 3.3%
[0210] Solids content: 100%
[0211] Viscosity (23.degree. C., D=100 l/s): 1300 mPas
Example 4
[0212] Production of a Polyisocyanate Having a Alkoxysilyl
Groups
[0213] 756 g (4.5 mol) of hexamethylene diisocyanate (HDI) were
introduced under dry nitrogen with stirring at a temperature of
80.degree. C. and 0.1 g of zinc(II) 2-ethyl-1-hexanoate as catalyst
were added. Over a period of about 30 minutes, 294 g (1.5 mol) of
mercaptopropyltrimethoxysilane were added dropwise, the temperature
of the mixture rising to up to 85.degree. C. owing to the
exothermic reaction. Stirring of the reaction mixture was continued
at 85.degree. C. until, after about 2 hours, the NCO content had
dropped to 34.9%. The catalyst was deactivated by addition of 0.1 g
of orthophosphoric acid and the unreacted monomeric HDI was removed
in a thin-film evaporator at a temperature of 130.degree. C. and a
pressure of 0.1 mbar. This gave 693 g of a virtually colorless,
clear polyisocyanate mixture having the following characteristics
and composition:
[0214] NCO content: 11.8%
[0215] Si content: 6.1%
[0216] Monomeric HDI: 0.06%
[0217] Viscosity (23.degree. C., shear gradient D=100 l/s): 452
mPas
[0218] Thiourethane: 0.0 mol %
[0219] Thioallophanate: 99.0 mol %
[0220] Isocyanurate groups: 1.0 mol %.
[0221] Catalysts
[0222] Cat.1: Production of a Catalytic Potassium Acetate
18-Crown-6 Solution in Diethylene Glycol
[0223] 1.77 g of potassium acetate (Sigma Aldrich), 4.75 g of the
crown ether 18-crown-6 from Merck KGaA and 31.15 g of diethylene
glycol from Sigma Aldrich were weighed in and stirred for several
hours until a clear solution was formed.
[0224] Cat. 2: Tetrabutylammonium Benzoate (TBAB)
[0225] TBAB (tetrabutylammonium benzoate from Sigma Aldrich) was
used as a 10% solution in MPA (1-methoxy-2-propyl acetate;
1,2-propylene glycol monomethyl ether acetate).
[0226] Use Example:
[0227] The coating compositions were produced by initially charging
the polyisocyanates having alkoxysilyl groups/the mixture according
to example 3 and subsequently adding the respective catalyst
solutions. Stirring was carried out using a Speed Mixer (Hausschild
Engineering, type DAC 150.1 FVZ) at 2750 rpm for 1 min. The
clearcoats were subsequently applied to a glass sheet using a 100
.mu.m film casting frame (Byk Gardner) and dried in a recirculating
air drying cabinet for 10 minutes at 140.degree. C. After cooling
(10 min RT) the films were subjected to visual assessment and the
first Konig pendulum damping measurements were taken.
TABLE-US-00001 Comparison Inventive Comparison Inventive Example 5
6 7 8 Product according to example 4 30.00 g 30.00 g 30.00 g 30.00
g Cat. 1 0.94 g 0.94 g Cat. 2 1.50 g 1.50 g Total amount of product
+ catalyst 30.00 g 30.94 g 31.50 g 32.44 g Curing: 10 min,
140.degree. C. Coating appearance clear, wet clear, dry clear, dry
clear, dry but rubbery, scrapeable Pendulum immediately measurable
14 s not 13 s damping measurable after 1 d RT -- 17 s -- 20 s after
3 d RT -- 17 s -- 18 s after 7 d RT -- 45 s -- 22 s after 14 d RT
-- 70 s -- 30 s Solvent xylene -- 1 -- 0 resistance
1-methoxyprop-2-yl -- 1 -- 0 after 5 min.; acetate sheets after
ethyl acetate -- 2 -- 2 14 d RT acetone -- 2 -- 2 -- = not
measured
[0228] To verify the completeness of the NCO reaction the NCO
reduction was investigated by IR spectroscopy for the compositions
according to examples 6 and 8.
[0229] The coating compositions were produced by weighing in the
silane-modified polyisocyanates with the catalysts and their
mixtures and subsequently stirring in the Speed Mixer (Hausschild
Engineering, type DAC 150.1 FVZ) at 2750 rpm for 1 min.
TABLE-US-00002 Composition according to example 6 8 Integration or
NCO (2380-2170) cm.sup.-1 Liquid 100% 100% Dry, immediately 1% 1%
after curing
[0230] The test lacquers were analyzed directly (wet lacquer) with
an FT-IR spectrometer (Tensor 11 with platinum ATR unit (diamond
crystal) from Bruker). The clearcoat was subsequently applied to a
glass sheet using a 100 .mu.m film casting frame and dried in a
recirculating air drying cabinet for 10 minutes at 140.degree. C.
and then immediately after the baking removed as a clearcoat film
and reanalyzed.
[0231] The isocyanate reaction is characterized by tracking the
intensity of the NCO peak (using an integration in the wavenumber
range of 2380-2170 cm.sup.-1), wherein the first measurement of the
wet lacquer material after mixing of the components is set to 100%
as the starting value. All further measurements (after application,
thermal treatment and/or storage) are then calculated relative to
the starting value (ratio formation).
[0232] In the measurement on an ATR crystal the intensity of the
spectrum is dependent on the penetration depth of the IR beam into
the material to be measured and on the covering of the crystal
surface. This penetration depth is in turn dependent on the
refractive index of the material. Since the refractive index of the
wet lacquer differs from the refractive index of the baked
clearcoat film and a comparable covering of the crystal surface
cannot be ensured for different measurements (on the wet lacquer/on
the clearcoat) the ratio calculation must include a correction of
both effects by virtue of all spectra being normalized to the CH
stretching vibration peak (wavenumber range 3000-2800
cm.sup.-1).
[0233] Examples 6 and 8 (inventive) show, in contrast to the
comparative examples 5 and 7 that, the trimerization reaction
starts only when the catalyst cat. I is present. The IR
measurements verify the virtually complete conversion of the NCO
groups. Subsequent post-curing upon storage must then be ascribed
to the second curing mechanism of the alkoxysilyl groups. Without
catalyst (5) or only with a catalyst (7) which catalyzes the
hydrolysis/condensation of alkoxysilyl groups at the chosen
temperature, no cured films are produced.
TABLE-US-00003 Inventive Inventive Inventive Inventive Example 8 9
10 11 Product according to example 4 30.00 g Product according to
example 1 30.00 g Product according to example 2 30.00 g Product
according to example 3 30.00 g Cat. 1 0.94 g 0.94 g 0.94 g 0.94 g
Cat. 2 1.50 g 1.50 g 1.50 g 1.50 g Total amount of product +
catalyst 32.44 g 32.44 g 32.44 g 32.44 g Curing: 10 min,
140.degree. C. Coating appearance clear, dry clear, dry clear, dry
clear, dry Pendulum damping immediately 13 s 24 s 24 s 63 s after 1
d RT 20 s 112 s 70 s 78 s after 3 d RT 18 s 166 s 155 s 161 s after
7 d RT 22 s 173 s 184 s 176 s after 14 d RT 30 s 180 s 195 s 184 s
Solvent resistance xylene 0 0 1 1 after 5 min.; sheets
1-methoxyprop-2-yl 0 0 1 1 after 14 d RT acetate ethyl acetate 2 1
2 2 acetone 2 2 2 2
[0234] Examples 8 to 11 show that the properties of the inventive
polyisocyanurate plastics can be varied with respect to hardness
and solvent resistance.
[0235] The scratch resistance of the coated glass sheets stored for
21 days according to examples 6, 8, 9, 10 and 11 in comparison with
a two component polyurethane lacquer was tested. As comparative
example 12, 49.06 g of Setalux.RTM. D A 665 BA/X, 65% in butyl
acetate/xylene (3:1) (polyacrylate polyol from Nuplex, DE) and 0.50
g of BYK-331, 10% in 1-methoxyprop-2-yl acetate (flow assistant
from BYK, DE), were mixed with 16.56 g of Desmodur.RTM. N 3300
using a Speed Mixer (Hausschild Engineering, type DAC 150.1 FVZ) at
2750 rpm for 1 min. The clearcoat was subsequently applied to to a
glass sheet using a 100 .mu.m film casting frame (Byk Gardner) and
dried in a recirculating air drying cabinet for 30 minutes at
140.degree. C. The lacquer according to comparative example 12 was
likewise stored for 21 days at RT.
[0236] The determination of scratch resistance by means of the
hammer test gave the following values:
TABLE-US-00004 Example 6 8 9 10 11 12 In- In- In- In- In- Com-
ventive ventive ventive ventive ventive parison Delta 122 92 60 81
139 216 haze
[0237] The inventive examples exhibit a smaller increase in haze
upon scratching with steel wool than the comparison.
* * * * *