U.S. patent application number 13/979156 was filed with the patent office on 2013-11-14 for epoxy resin composition.
This patent application is currently assigned to Huntsman International LLC. The applicant listed for this patent is Christiaan Debien, Christian Esbelin, Hans Godelieve Guido Verbeke, Hugo Verbeke. Invention is credited to Christiaan Debien, Christian Esbelin, Hans Godelieve Guido Verbeke, Hugo Verbeke.
Application Number | 20130303694 13/979156 |
Document ID | / |
Family ID | 44315244 |
Filed Date | 2013-11-14 |
United States Patent
Application |
20130303694 |
Kind Code |
A1 |
Debien; Christiaan ; et
al. |
November 14, 2013 |
Epoxy Resin Composition
Abstract
Curable composition obtained by combining and mixing an epoxy
resin composition comprising an epoxy resin, a monool and/or polyol
and a a compound comprising a carboxamide group, and a
polyisocyanate composition comprising a polyisocyanate, a lithium
halide and a urea compound, wherein the number of moles of lithium
halide per isocyanate equivalent ranges of from 0.0001-0.04 and the
number of urea+biuret equivalents per isocyanate equivalent of from
0.0001-0.4. The epoxy resin composition is claimed as well.
Inventors: |
Debien; Christiaan;
(Holsbeek, BE) ; Esbelin; Christian; (Schaerbeek,
BE) ; Verbeke; Hans Godelieve Guido; (Lubbeek,
BE) ; Verbeke; Hugo; (Leuven, BE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Debien; Christiaan
Esbelin; Christian
Verbeke; Hans Godelieve Guido
Verbeke; Hugo |
Holsbeek
Schaerbeek
Lubbeek
Leuven |
|
BE
BE
BE
BE |
|
|
Assignee: |
Huntsman International LLC
The Woodlands
TX
|
Family ID: |
44315244 |
Appl. No.: |
13/979156 |
Filed: |
November 7, 2011 |
PCT Filed: |
November 7, 2011 |
PCT NO: |
PCT/EP2011/069562 |
371 Date: |
July 11, 2013 |
Current U.S.
Class: |
524/728 ;
252/182.28 |
Current CPC
Class: |
C08L 63/00 20130101;
C08G 18/7831 20130101; C08G 18/7825 20130101; C08K 5/20 20130101;
C08G 18/3829 20130101; C08G 18/092 20130101; C08G 18/4812 20130101;
C08G 18/225 20130101; C08G 18/4045 20130101; C08G 18/792 20130101;
C08G 2105/02 20130101 |
Class at
Publication: |
524/728 ;
252/182.28 |
International
Class: |
C08K 5/20 20060101
C08K005/20 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 31, 2011 |
EP |
11152720.6 |
Claims
1. An epoxy resin composition comprising an epoxy resin, a monool
and/or a polyol and a carboxamide compound which comprises a
carboxamide group having the structure --CO--NH.sub.2 wherein the
number of hydroxy equivalents per epoxy equivalent is 0.02-100 and
preferably 0.03-50 and most preferably 0.05-10 and the number of
carboxamide equivalents per epoxy equivalent is 0.0005-1 and
preferably 0.005-0.7 and most preferably of 0.01-0.5.
2. The epoxy resin composition according to claim 1 wherein the
monool and/or the polyol has an average nominal functionality of
1-8 and an average molecular weight of 32-8000 and wherein the
number of hydroxy equivalents per epoxy equivalent is 0.05-10.
3. The epoxy resin composition according to claim 1 wherein the
carboxamide compound has the structure NH.sub.2--CO--R wherein R is
1) hydrogen (--H), 2) --NR.sub.1R.sub.2, 3) hydrocarbyl having 1-20
carbon atoms and optionally comprising hydroxy, ether, halogen
and/or amine groups, or 4) --R.sub.3--CO--NH.sub.2, wherein R.sub.1
and R.sub.2, independently from each other, are selected from
hydrogen, hydroxy, halogen and hydrocarbyl groups which hydrocarbyl
groups have 1-10 carbon atoms and optionally comprise hydroxy,
ether, halogen and/or amine groups and wherein R.sub.3 is a
bivalent hydrocarbon radical having up to 8 carbon atoms and
mixtures of such compounds and wherein the number of carboxamide
equivalents per epoxy equivalent is 0.01-0.5.
4. The epoxy resin composition according to claim 1 wherein the
carboxamide compound has the structure NH.sub.2--CO--R wherein R is
1) --NR.sub.1R.sub.2, 2) alkyl having 1-10 carbon atoms and
optionally comprising 1-3 hydroxy and/or ether groups, 3) phenyl or
4) tolyl, wherein R.sub.1 and R.sub.2, independently from each
other, are selected from hydrogen, hydroxy, phenyl, tolyl and alkyl
having 1-6 carbon atoms and optionally comprising an hydroxy and/or
an ether group and mixtures of such compounds.
5. A process for making a composition according to claim 1 wherein
a mixture of the polyol and carboxamide compound is combined and
mixed with the epoxy resin.
6. A curable composition comprising a polyisocyanate composition,
comprising a polyisocyanate, a lithium halide and a urea compound,
having an average molecular weight of 500-15000 and optionally
comprising biuret groups, and an epoxy resin composition according
to claim 1, wherein the number of moles of lithium halide per
isocyanate equivalent ranges of from 0.0001-0.04 and the number of
urea+biuret equivalents per isocyanate equivalent ranges of from
0.0001-0.4 and the number of epoxy equivalents per isocyanate
equivalent ranges of from 0.003-1.
7. The curable composition according to claim 6, wherein the urea
compound does not comprise other isocyanate-reactive groups than
urea groups and wherein the number of urea+biuret equivalents per
isocyanate equivalent is 0.001-0.2 and wherein the urea compound
has been prepared by reacting a methylene diphenyl diisocyanate or
a polyisocyanate comprising a methylene diphenyl diisocyanate or a
mixture of these polyisocyanates with a polyoxyalkylene monoamine
comprising oxypropylene groups in an amount of at least 50% by
weight calculated on the total weight of the monoamine molecule and
having an average molecular weight of 200-3000 and wherein the
amine is a primary amine and wherein the number of urea+biuret
equivalents per mole of lithium halide is 0.5-60.
8. The curable composition according to claim 6, wherein the
polyisocyanate is a methylene diphenyl diisocyanate or a
polyisocyanate composition comprising methylene diphenyl
diisocyanate or a mixture of such polyisocyanates.
9. The curable composition according to claim 6, wherein the amount
of lithium halide is 0.00015-0.025 moles per isocyanate
equivalent.
10. The curable composition according to claim 6, wherein the
lithium halide is lithium chloride.
11. The curable composition according to claim 6, wherein the epoxy
resin is liquid at 20-25.degree. C.
12. A process for making a curable composition according to claim
6, by combining and mixing the polyisocyanate composition described
in claim 6 and the epoxy resin composition described in claim 6,
the amount of epoxy resin composition being such that the number of
epoxy equivalents per isocyanate equivalent ranges from
0.003-1.
13. A polyurethane polyisocyanurate material made by allowing a
curable composition according to claim 6 to react at elevated
temperature.
14. A polyurethane polyisocyanurate material obtainable by allowing
a curable composition according to claim 6 to react at elevated
temperature.
15. A process for making a polyurethane polyisocyanurate material
according to claim 13 by allowing the curable composition according
to claim 6 to react at elevated temperature.
16. (canceled)
Description
[0001] The present invention is related to an epoxy resin
composition and a curable composition made by combining said epoxy
resin composition with a polyisocyanate composition. Further the
present invention is related to a process for preparing said epoxy
resin composition and said curable composition. Still further the
present invention is concerned with a process to prepare a
polyurethane polyisocyanurate material by allowing the curable
composition to react and to a polyurethane polyisocyanurate
material made by allowing such curable composition to react.
[0002] Recently a curable composition has been proposed having a
pot-life up to 17 hours which comprises a polyisocyanate, a lithium
halide, a urea compound and an epoxy resin; see PCT/EP2010/054492.
The urea compounds used in PCT/EP2010/054492 are prepared by
reacting polyisocyanates (R.sub.1--NCO) with amines
(R.sub.2--NH.sub.2) and are referred to as urea compounds and have
following structure R.sub.1--NH--CO--NH--R.sub.2, R.sub.1 and
R.sub.2 both not being hydrogen.
[0003] Surprisingly we have found that the pot-life of the curable
composition could be significantly improved towards pot-lifes up to
300 hours and longer by using an epoxy resin composition which
comprises a compound which comprises a carboxamide group having the
structure --CO--NH.sub.2, without negatively influencing the curing
of the curable composition afterwards.
[0004] Therefore the present invention relates to an epoxy resin
composition comprising an epoxy resin, a monool and/or a polyol and
a compound comprising a carboxamide group wherein the number of
hydroxy equivalents per epoxy equivalent is 0.02-100 and preferably
0.03-50 and most preferably 0.05-10 and the number of carboxamide
equivalents per epoxy equivalent is 0.0005-1 and preferably
0.005-0.7 and most preferably of 0.01-0.5.
[0005] Further the present invention relates to a process to
prepare such an epoxy resin composition wherein a mixture of the
monool and/or the polyol and the compound comprising the
carboxamide group is combined and mixed with the epoxy resin. The
relative amounts of the ingredients are chosen such that the epoxy
resin composition comprises these ingredients in the above given
amounts.
[0006] Still further the present invention relates to a curable
composition obtained by combining and mixing a polyisocyanate
composition, comprising a polyisocyanate, a lithium halide and a
urea compound, having an average molecular weight of 500-15000 and
optionally comprising biuret groups, and an epoxy resin
composition, as defined above, wherein the number of moles of
lithium halide per isocyanate equivalent ranges from 0.0001-0.04,
the number of urea+biuret equivalents per isocyanate equivalent
ranges from 0.0001-0.4 and the number of epoxy equivalents per
isocyanate equivalent ranges from 0.003-1.
[0007] Still further the present invention is concerned with a
process to prepare a polyurethane polyisocyanurate material by
allowing the above defined curable composition to react at elevated
temperature and with the polyurethane polyisocyanurate material
prepared in this way.
[0008] Finally the present invention relates to the use of a
compound which comprises a carboxamide group having the structure
--CO--NH.sub.2 for improving the pot-life of a curable
polyisocyanate composition.
[0009] The use of lithium chloride and compounds comprising urea
groups has been disclosed by Sheth, Aneja and Wilkes in Polymer 45
(2004) 5979-5984. They studied the influence of the extent of
hydrogen bonding in mediating the long-range connectivity and
percolation of the hard segment phase in model tri-segment
oligomeric polyurethanes using LiCl as a molecular probe.
[0010] In U.S. Pat. No. 5,086,150 an isocyanate-terminated
prepolymer is reacted with a diamine in the presence of a rather
high amount of LiCl to prepare an elastomer solution which is
stable for at least two days. At the beginning of the reaction the
number of moles of lithium chloride per isocyanate equivalent is
rather high; the lithium chloride is used to act as a solubilizer.
At the beginning of the reaction, the composition is not stable and
does not contain urea and at the end of the reaction it is an
elastomer and not an isocyanate composition anymore. The product
obtained is an elastomer solution used for making threads and
films.
[0011] The use of isocyanates and epoxides together with LiCl has
been disclosed in Russian Chemical Reviews 52(6) 1983, 576-593. The
reaction is influenced by the nature of the catalyst. In the
presence of metal halides an activated complex is formed which
ultimately gives an oxazolidone. One of the side reactions is the
formation of isocyanurate rings which decompose to oxazolidone on
treatment with epoxides. Further it has been disclosed therein that
epoxides are capable of cleaving urea linkages with formation of
oxazolidones.
[0012] U.S. Pat. No. 4,658,007 discloses a process for preparing
oxazolidone containing polymer using organoantimony iodide catalyst
by reacting a polyisocyanate and a polyepoxide.
[0013] U.S. Pat. No. 5,326,833 discloses a composition comprising a
polyisocyanate, an epoxide and a catalyst consisting of a solution
of an alkali halide, like LiCl, in a polyoxyalkylenic compound.
These compositions are able to gel rapidly between 0.degree. C. and
70.degree. C. Juan et al discuss in the Journal of East China
University of Science and Technology Vol. 32, No 11, 2006,
1293-1294 the influence of LiCl on the morphology structure and
properties of polyurethane-urea. It shows that the viscosity of
polyurethane urea solutions first decreases and subsequently
increases. The polyurethane urea was made by reacting
polyepoxypropane glycol and isophorone diisocyanate with excess
polyisocyanate.
[0014] In U.S. Pat. No. 3,517,039 acylated urea polyisocyanates are
made by reacting an organic diisocyanate with an organic
monocarboxylic acid. These polyisocyanates are used in the
preparation of polyurethanes, especially when small amounts of
branching are desirable.
[0015] In U.S. Pat. No. 3,970,600 stable solutions of
isocyanurate-polyisocyanates containing amide and/or acylurea
groups have been described. They avoid deposition of fine or coarse
crystalline solids in polyisocyanates comprising isocyanurate
groups. First a polyisocyanate is reacted with polybasic carboxylic
acid to prepare a polyisocyanate with amide
and/or--substituted--acylurea groups. Then this polyisocyanate is
trimerized to form an isocyanurate-polyisocyanate and this
conversion is stopped by adding acid.
[0016] In JP 2-110123 an aliphatic diisocyanate is trimerized to
prepare polyisocyanates which have an isocyanurate structure using
a catalyst and a deactivating agent once the desired degree of
conversion has been attained. The deactivating agent has the
structure --CO--NH.sub.2 or --SO--NH.sub.2 and may be urea, methyl
urea, 1,1-dimethyl urea, phenyl carbamate, ethylcarbamate or
butylcarbamate. Subsequently deactivated catalyst, excess
diisocyanate and solvent, if used, are eliminated. By using this
deactivating agent the polyisocyanate comprising polyisocyanurate
structure shows a lower degree of discolouration.
[0017] WO 2008/068198 and US 2010/0022707 disclose a process for
preparing an oligomerized polyisocyanate using a catalyst wherein a
deactivator is used once the desired conversion has been obtained
followed by removal of the polyisocyanate which was not converted.
The deactivator may be selected from urea and urea containing
compounds, amongst others.
[0018] EP 585835 discloses a process for preparing isocyanurate and
urethane group containing polyisocyanate mixtures by partially
cyclizing diisocyanates in the presence of a trimerization
catalyst, deactivating the trimerization catalyst when the desired
conversion is achieved, and subsequently reacting the resultant
isocyanurate group containing polyisocyanate with hydroxyl
compounds and then separating off the monomeric diisocyanate.
[0019] In the context of the present invention the following terms
have the following meaning: [0020] 1) isocyanate index or NCO index
or index: [0021] the ratio of NCO-groups over isocyanate-reactive
hydrogen atoms present in a formulation, given as a percentage:
[0021] [ NCO ] .times. 100 [ active hydrogen ] ( % ) . ##EQU00001##
[0022] In other words the NCO-index expresses the percentage of
isocyanate actually used in a formulation with respect to the
amount of isocyanate theoretically required for reacting with the
amount of isocyanate-reactive hydrogen used in a formulation.
[0023] It should be observed that the isocyanate index as used
herein is considered from the point of view of the actual
polymerisation process preparing the material involving the
isocyanate ingredient and the isocyanate-reactive ingredients. Any
isocyanate groups consumed in a preliminary step to produce
modified polyisocyanates (including such isocyanate-derivatives
referred to in the art as prepolymers) or any active hydrogens
consumed in a preliminary step (e.g. reacted with isocyanate to
produce modified polyols or polyamines) are not taken into account
in the calculation of the isocyanate index. Only the free
isocyanate groups and the free isocyanate-reactive hydrogens
(including those of water, if used) present at the actual
polymerisation stage are taken into account. [0024] 2) The
expression "isocyanate-reactive hydrogen atoms" as used herein for
the purpose of calculating the isocyanate index refers to the total
of active hydrogen atoms in hydroxyl and amine groups present in
the reactive compositions; this means that for the purpose of
calculating the isocyanate index at the actual polymerisation
process one hydroxyl group is considered to comprise one reactive
hydrogen, one primary amine group is considered to comprise one
reactive hydrogen and one water molecule is considered to comprise
two active hydrogens. [0025] 3) Reaction system: a combination of
components wherein the polyisocyanates are kept in one or more
containers separate from the isocyanate-reactive components. [0026]
4) The term "average nominal hydroxyl functionality" (or in short
"functionality") is used herein to indicate the number average
functionality (number of hydroxyl groups per molecule) of the
polyol or polyol composition on the assumption that this is the
number average functionality (number of active hydrogen atoms per
molecule) of the initiator(s) used in their preparation although in
practice it will often be somewhat less because of some terminal
unsaturation. [0027] 5) The word "average" refers to number average
unless indicated otherwise.
[0028] The epoxy resin used in the epoxy resin composition
according to the present invention preferably is selected from any
epoxy resin which is liquid at 20.degree. C.-25.degree. C.
[0029] Examples of epoxy resins are:
[0030] I) Polyglycidyl and poly(.beta.-methylglycidyl) esters,
obtainable by reacting a compound having at least two carboxyl
groups in the molecule and, respectively, epichlorohydrin and
.beta.-methylepichlorohydrin. The reaction is expediently effected
in the presence of bases.
[0031] Aliphatic polycarboxylic acids can be used as the compound
having at least two carboxyl groups in the molecule. Examples of
such polycarboxylic acids are oxalic acid, succinic acid, glutaric
acid, adipic acid, pimelic acid, suberic acid, azelaic acid and
dimerized or trimerized linoleic acid.
[0032] However, cycloaliphatic polycarboxylic acids, such as, for
example, tetrahydrophthalic acid, 4-methyltetrahydrophthalic acid,
hexahydrophthalic acid or 4-methylhexa-hydrophthalic acid, may also
be used.
[0033] Furthermore, aromatic polycarboxylic acids, such as, for
example, phthalic acid, isophthalic acid or terephthalic acid, may
be used.
[0034] II) Polyglycidyl or poly(.beta.-methylglycidyl)ethers,
obtainable by reacting a compound having at least two free
alcoholic hydroxyl groups and/or phenolic hydroxyl groups with
epichlorohydrin or .beta.-methylepichlorohydrin under alkaline
conditions or in the presence of an acidic catalyst with subsequent
treatment with alkali.
[0035] The glycidyl ethers of this type are derived, for example,
from acyclic alcohols, for example from ethylene glycol, diethylene
glycol or higher poly(oxyethylene) glycols, propane-1,2-diol or
poly(oxypropylene) glycols, propane-1,3-diol, butane-1,4-diol,
poly(oxytetramethylene) glycols, pentane-1,5-diol, hexane-1,6-diol,
hexane-2,4,6-triol, glycerol, 1,1,1-trimethylolpropane,
pentaerythritol or sorbitol, and from polyepichlorohydrins. Further
glycidyl ethers of this type are derived from cycloaliphatic
alcohols, such as 1,4-cyclohexanedimethanol,
bis(4-hydroxycyclohexyl)methane or
2,2-bis(4-hydroxycyclohexyl)propane, or from alcohols which contain
aromatic groups and/or further functional groups, such as
N,N-bis(2-hydroxyethyl)aniline or
p,p'-bis(2-hydroxyethylamino)-diphenylmethane.
[0036] The glycidyl ethers may also be based on mononuclear
phenols, such as, for example, p-tert-butylphenol, resorcinol or
hydroquinone, or on polynuclear phenols, such as, for example,
bis(4-hydroxyphenyl)methane, 4,4'-dihydroxybiphenyl,
bis(4-hydroxyphenyl) sulphone,
1,1,2,2-tetrakis(4-hydroxyphenyl)ethane,
2,2-bis(4-hydroxyphenyl)propane or
2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane.
[0037] Further suitable hydroxy compounds for the preparation of
glycidyl ethers are novolaks, obtainable by condensation of
aldehydes, such as formaldehyde, acetaldehyde, chloral or
furfuraldehyde, with phenols or bisphenols which are unsubstituted
or substituted by chlorine atoms or C.sub.1-C.sub.9-alkyl groups,
such as, for example, phenol, 4-chlorophenol, 2-methylphenol or
4-tert-butylphenol.
[0038] III) Poly(N-glycidyl) compounds, obtainable by
dehydrochlorination of the reaction products of epichlorohydrin
with amines which contain at least two amine hydrogen atoms. These
amines are, for example, aniline, n-butylamine,
bis(4-aminophenyl)methane, m-xylylenediamine or
bis(4-methylaminophenyl)methane.
[0039] The poly(N-glycidyl) compounds also include triglycidyl
isocyanurate, N,N'-diglycidyl derivatives of cycloalkyleneureas,
such as ethyleneurea or 1,3-propyleneurea, and diglycidyl
derivatives of hydantoins, such as of 5,5-dimethylhydantoin.
[0040] IV) Poly(S-glycidyl) compounds, for example di-S-glycidyl
derivatives, which are derived from dithiols, such as, for example,
ethane-1,2-dithiol or bis(4-mercaptomethylphenyl)ether.
[0041] V) Cycloaliphatic epoxy resins, such as, for example,
bis(2,3-epoxycyclopentyl)ether, 2,3-epoxycyclopentyl glycidyl
ether, 1,2-bis(2,3-epoxycyclopentyloxy)ethane or
3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexanecarboxylate.
[0042] It is also possible to use epoxy resins in which the
1,2-epoxy groups are bonded to different hetero atoms or functional
groups; these compounds include, for example, the N,N,O-triglycidyl
derivative of 4-aminophenol, the glycidyl ether-glycidyl ester of
salicylic acid,
N-glycidyl-N'-(2-glycidyloxypropyl)-5,5-dimethylhydantoin or
2-glycidyloxy-1,3-bis(5,5-dimethyl-1-glycidylhydantoin-3-yl)propane.
[0043] Particularly preferred are those mentioned in I and II and
most preferred are those mentioned in II.
[0044] The monool and/or polyol used in the epoxy resin composition
according to the present invention preferably has an average
nominal hydroxy functionality of 1-8 and an average molecular
weight of 32-8000. Mixtures of monools and/or polyols may be used
as well.
[0045] Examples of such monools are methanol, ethanol, propanol,
butanol, phenol, cyclohexanol and hydrocarbon monools having an
average molecular weight of 200-5000 like aliphatic and polyether
monools. Examples of polyols are ethylene glycol, diethylene
glycol, triethylene glycol, propylene glycol, dipropylene glycol,
tripropylene glycol, trimethylol propane, sorbitol, sucrose,
glycerol, ethanediol, propanediol, butanediol, pentanediol,
hexanediol, aromatic and/or aliphatic polyols having more carbon
atoms than these compounds and having a molecular weight of up to
8000, polyester polyols having an average molecular weight of
200-8000, polyether polyester polyols having an average molecular
weight of 200-8000 and polyether polyols having an average
molecular weight of 200-8000. Such monools and polyols are
commercially available. Useful examples are Daltocel F526, Daltocel
F555 and Daltocel F442, which are all polyether triols from
Huntsman, Voranol P400 and Alcupol R1610, which are polyether
polyols from DOW and Repsol, respectively, and Priplast 1838 and
3196 which are high molecular weight polyester polyols from Croda,
and Capa 2043 polyol, a linear polyesterdiol of average MW of about
400 from Perstorp, and K-flex polyols 188 and A308 which are
polyester polyols from King Industries having a MW of about 500 and
430 respectively, and aromatic polyester polyols like Stepanpol
PH56 and BC180 having average molecular weights of about 2000 and
600 respectively, and Neodol 23E which is an aliphatic monool from
Shell.
[0046] Most preferred are polyester and polyether polyols having an
average molecular weight of 200-6000 and an average nominal
functionality of 2-4.
[0047] The compound comprising a carboxamide group (also further
referred to as the "carboxamide" compound) preferably is selected
from a compound according to the formula
NH.sub.2--CO--R wherein R is 1) hydrogen (--H), 2)
--NR.sub.1R.sub.2, 3) hydrocarbyl having 1-20 carbon atoms and
optionally comprising hydroxy, ether, halogen and/or amine groups,
or 4) --R.sub.3--CO--NH.sub.2, wherein R.sub.1 and R.sub.2,
independently from each other, are selected from hydrogen, hydroxy,
halogen and hydrocarbyl groups which hydrocarbyl groups have 1-10
carbon atoms and optionally comprise hydroxy, ether, halogen and/or
amine groups and wherein R.sub.3 is a bivalent hydrocarbon radical
having up to 8 carbon atoms. Mixtures of these carboxamide
compounds may be used as well. Preferably such carboxamides have a
molecular weight of at most 499.
[0048] The hydrocarbyl groups in these carboxamides may be linear
or branched, saturated or unsaturated and cyclic or non-cyclic;
they may be aliphatic, aromatic or araliphatic.
[0049] More preferred carboxamides are those wherein R is 1)
--NR.sub.1R.sub.2, 2) alkyl having 1-10 carbon atoms and optionally
comprising 1-3 hydroxy and/or ether groups, 3) phenyl or 4) tolyl,
wherein R.sub.1 and R.sub.2, independently from each other, are
selected from hydrogen, hydroxy, phenyl, tolyl and alkyl having 1-6
carbon atoms and optionally comprising an hydroxy and/or an ether
group. Mixtures of such more preferred compounds are also more
preferred.
[0050] Examples of very useful carboxamide compounds are according
to the formula NH.sub.2--CO--R wherein R is as defined below:
TABLE-US-00001 R Name --NH.sub.2 Urea --NHOH Hydroxyurea
--NH(CH.sub.3) N-Methyl urea --N(CH.sub.3).sub.2 1,1-dimethyl urea
--N(C.sub.2H.sub.5).sub.2 1,1-diethyl urea --NH--C.sub.6H.sub.5
Phenylurea --NH--C.sub.6H.sub.4--CH.sub.3 Tolylurea --H Formamide
--CH.sub.3 Ethanamide --C.sub.2H.sub.5 Propionamide
--OC.sub.2H.sub.5 Ethyl carbamate --OC.sub.4H.sub.9 Butyl carbamate
--OC.sub.6H.sub.5 Phenyl carbamate --OCH.sub.2--CH.sub.2--OH
Hydroxyethyl carbamate --OCH(CH.sub.3)--CH.sub.2OH Hydroxypropyl
carbamate --CH(CH.sub.3)--OH Lactamide --C.sub.6H.sub.5 Benzamide
##STR00001## Nicotinamide
[0051] Most preferably urea is used. It is to be noted that in
calculating the number of carboxamide equivalents urea is regarded
as containing 2 carboxamide groups.
[0052] In order to make the epoxy resin composition according to
the present invention the above described carboxamide compound is
combined and mixed with the above described monool and/or polyol
preferably at ambient pressure and a temperature between 10.degree.
C. and 120.degree. C. Although special mixing operations may be
used, normal mixing is sufficient. The mixture so obtained
optionally may be cooled if it was mixed at elevated temperature;
subsequently it is mixed with the above described epoxy resin
preferably at ambient pressure and a temperature between 10.degree.
C. and 120.degree. C. The relative amounts of the epoxy resin, the
polyol and the carboxamide compound are chosen in such a way that
the aforementioned hydroxy/epoxy and carboxamide/epoxy ratios are
met.
[0053] The polyisocyanate used for making the polyisocyanate
composition used according to the present invention may be selected
from aliphatic and, preferably, aromatic polyisocyanates. Preferred
aliphatic polyisocyanates are hexamethylene diisocyanate,
isophorone diisocyanate, methylene dicyclohexyl diisocyanate and
cyclohexane diisocyanate and preferred aromatic polyisocyanates are
toluene diisocyanate, naphthalene diisocyanate, tetramethylxylene
diisocyanate, phenylene diisocyanate, tolidine diisocyanate and, in
particular, methylene diphenyl diisocyanate (MDI) and
polyisocyanate compositions comprising methylene diphenyl
diisocyanate (like so-called polymeric MDI, crude. MDI, uretonimine
modified MDI and prepolymers having free isocyanate groups made
from MDI and polyisocyanates comprising MDI) and mixtures of such
polyisocyanates. MDI and polyisocyanate compositions comprising MDI
are most preferred and especially those selected from 1) a
diphenylmethane diisocyanate comprising at least 35%, preferably at
least 60% by weight of 4,4'-diphenylmethane diisocyanate
(4,4'-MDI); 2) a carbodiimide and/or uretonimine modified variant
of polyisocyanate 1), the variant having an NCO value of 20% by
weight or more; 3) a urethane modified variant of polyisocyanate 1)
and/or 2), the variant having an NCO value of 20% by weight or more
and being the reaction product of an excess of polyisocyanate 1)
and/or 2) and of a polyol having an average nominal hydroxyl
functionality of 2-4 and an average molecular weight of at most
1000; 4) a diphenylmethane diisocyanate comprising a homologue
comprising 3 or more isocyanate groups; 5) prepolymers having an
NCO value of 5-30% by weight and being the reaction product of any
one or more of polyisocyanates 1)-4) and of a polyol having an
average nominal hydroxyl functionality of 2-4 and an average
molecular weight of more than 1000 and up to 8000; and 6) mixtures
of any of the aforementioned polyisocyanates.
[0054] Polyisocyanate 1) comprises at least 35% by weight of
4,4'-MDI. Such polyisocyanates are known in the art and include
pure 4,4'-MDI and isomeric mixtures of 4,4'-MDI, 2,4'-MDI and
2,2'-MDI. It is to be noted that the amount of 2,2'-MDI in the
isomeric mixtures is rather at an impurity level and in general
will not exceed 2% by weight, the remainder being 4,4'-MDI and
2,4'-MDI. Polyisocyanates as these are known in the art and
commercially available; for example Suprasec.RTM. MPR and 1306 ex
Huntsman (Suprasec is a trademark of the Huntsman Corporation or an
affiliate thereof which has been registered in one or more but not
all countries).
[0055] The carbodiimide and/or uretonimine modified variants of the
above polyisocyanate 1) are also known in the art and commercially
available; e.g. Suprasec.RTM. 2020, ex Huntsman. Urethane modified
variants of the above polyisocyanate 1) are also known in the art,
see e.g. The ICI Polyurethanes Book by G. Woods 1990, 2.sup.nd
edition, pages 32-35. Polyisocyanate 4) is also widely known and
commercially available. These polyisocyanates are often called
crude MDI or polymeric MDI. Examples are Suprasec.RTM. 2185,
Suprasec.RTM. 5025 and Suprasec.RTM. DNR ex Huntsman.
[0056] The prepolymers (polyisocyanate 5)) are also widely known
and commercially available. Examples are Suprasec.RTM. 2054 and
Suprasec.RTM. 2061, both ex Huntsman.
[0057] Mixtures of the aforementioned polyisocyanates may be used
as well, see e.g. The ICI Polyurethanes Book by G. Woods 1990,
2.sup.nd edition pages 32-35. An example of such a commercially
available polyisocyanate is Suprasec.RTM. 2021 ex Huntsman.
[0058] The lithium halide used in the polyisocyanate composition
used according to the present invention is used in an amount of
0.0001-0.04 and preferably of 0.00015-0.025 and most preferably of
0.0005-0.02 moles per isocyanate equivalent and preferably is
selected from lithium chloride and lithium bromide. Lithium
chloride is most preferred.
[0059] The urea compound used in the polyisocyanate composition
used according to the present invention is used in such an amount
that the number of urea+biuret equivalents is 0.0001-0.4 and
preferably 0.001-0.2 and most preferably 0.001-0.05 per isocyanate
equivalent. Most preferably the number of urea+biuret equivalents
in the urea compound in the polyisocyanate composition per mole of
lithium halide ranges of from 0.5-60 and most preferably of from
0.5-30. The urea compound should not comprise other
isocyanate-reactive groups (i.e. other than urea groups). In
calculating the number of urea equivalents, the urea groups in the
carboxamide compounds having a molecular weight of at most 499, are
not taken into account.
[0060] The urea compound used in the polyisocyanate composition
used according to the present invention has an average molecular
weight of 500-15000 and preferably of 600-10000 and most preferably
of 800-8000. Such urea compounds are prepared by reacting
polyisocyanates and amines.
[0061] The polyisocyanates used to prepare such urea compound may
be selected from the polyisocyanates mentioned above. The
preferences mentioned above apply here as well. Most preferably
polyisocyanates 1) and 2) and mixtures thereof are used. The
polyisocyanate used to make the polyisocyanate composition
according to the present invention and the polyisocyanate used to
make the urea compound may be the same or different.
[0062] The amines used to prepare the urea compounds may be
monoamines or polyamines. Preferably monoamines, optionally
comprising a small amount of polyamines, are used. The average
amine functionality of such mixtures preferably is at most 1.2.
Most preferably only monoamines are used. Such amines preferably
are primary amines.
[0063] The molecular weight of the amines is selected in such a way
that once reacted with the selected polyisocyanate the molecular
weight of the urea compound obtained falls within the above ranges.
In general the molecular weight of the amines ranges of from
200-7500 and preferably of from 200-4500 and most preferably of
from 200-3000.
[0064] The amines may be selected from those known in the art like
amine-terminated hydrocarbons, polyesters, polyethers,
polycaprolactones, polycarbonates, polyamides and mixtures thereof.
Most preferred are amine-terminated polyoxyalkylene monoamines and
more in particular polyoxyethylene polyoxypropylene monoamines.
Preferably the oxypropylene content in these polyoxyalkylene
monoamines is at least 50 and preferably at least 75% by weight
calculated on the total weight of the monoamine molecule.
Preferably the polyoxyalkylene monoamines have a monoalkyl group at
the other end of the polymer chain, the alkyl group having 1-8 and
preferably 1-4 carbon atoms. Such monoamines are known in the art.
They are made by alkoxylating an alkylmonoalcohol having 1-8 carbon
atoms and by subsequently converting the polyoxyalkylene monool
into the monoamine. Such monoamines are commercially available.
Examples are Jeffamine.RTM. M-600 and M-2005, both ex Huntsman
(Jeffamine is a trademark of the Huntsman Corporation or an
affiliate thereof which has been registered in one or more but not
all countries). Mixtures of monoamines may be used as well.
[0065] In view of the above, a most preferred urea compound used in
the polyisocyanate composition used according to the present
invention is a urea compound obtained by reacting a methylene
diphenyl diisocyanate or a polyisocyanate comprising a methylene
diphenyl diisocyanate or a mixture of these polyisocyanates and a
polyoxyalkylene monoamine, comprising oxypropylene groups in an
amount of at least 75% by weight calculated on the total weight of
the monoamine molecule and having an average molecular weight of
200-3000 and wherein the amine is a primary amine.
[0066] The polyisocyanate and the monoamine are combined and mixed
and allowed to react. The reaction is exothermic and therefore does
not require heating and/or catalysis, although heat and/or
catalysis may be applied if this is regarded as convenient. For
instance it may be convenient to pre-heat the polyisocyanate and/or
the monoamine to 40-60.degree. C. and to mix them then. After
mixing, the temperature of the reacting mixture preferably is kept
below 90.degree. C. in order to avoid side reactions, like e.g.
biuret formation. In order to ensure that all the amine reacts, a
slight excess of polyisocyanate may be used; conducting the
reaction at an index of 101-110 is preferred therefore. After at
most 1 hour the reaction may be regarded as complete and the urea
compound is ready for use to make the polyisocyanate composition
used according to the present invention.
[0067] Since a small excess of polyisocyanate is used in preparing
the urea compound and since the urea compound in a next step is
added to a relatively large amount of polyisocyanate, some of the
urea groups might be converted to biuret groups. By controlling the
reaction temperature and the temperature of the subsequent mixing
steps, such biuret formation is avoided as much as possible. In
general, the number of urea groups which are converted into biuret
groups is less than 25% and preferably less than 10%.
[0068] The polyisocyanate composition used according to the present
invention is made by mixing the polyisocyanate, the urea compound
and the lithium halide in any order under ambient conditions or at
elevated temperature, e.g. at 40-70.degree. C. Preferably the
lithium halide is premixed with the urea compound and this mixture
is subsequently added to the polyisocyanate and mixed. Before
mixing the lithium halide and the urea compound, it may be
convenient to dissolve the lithium halide in a solvent, like in an
organic solvent like an alcohol, e.g. methanol or ethanol. The
dissolved lithium halide is then added to the urea compound.
Subsequently the solvent may be stripped off if desired. Premixing
and mixing is conducted under ambient conditions or at elevated
temperature, e.g. at 40-70.degree. C. and is done by means of
normal stirring. The relative amounts of the polyisocyanate, the
urea compound and the lithium halide are chosen in such a way that
the final polyisocyanate composition used according to the
invention has the relative amounts of isocyanate groups, urea
groups and lithium halide as has been described before. Without
wishing to be bound to any theory, the lithium halide is believed
to be present in dissociated form, complexed with the urea group as
a so-called bidentate complex.
[0069] The polyisocyanate composition is used to make a curable
composition according to the invention by combining and mixing the
epoxy resin composition and the polyisocyanate composition in such
relative amounts that the number of epoxy equivalents per
isocyanate equivalent ranges from 0.003-1 and preferably from
0.003-0.5 and most preferably from 0.005-0.25. These compositions
are preferably combined and mixed under ambient conditions. The
relative amounts of the ingredients are chosen in a way so as to
provide an index to the curable composition of 300-100000 and
preferably of 500-10000.
[0070] The curable composition so obtained has a good stability
under ambient conditions. It is used to make a polyurethane
polyisocyanurate material by allowing it to react at elevated
temperature. Therefore the invention is further concerned with a
polyurethane polyisocyanurate material made by allowing a curable
composition according to the present invention to react at elevated
temperature and with a polyurethane polyisocyanurate material
obtainable by allowing a curable composition according to the
present invention to react at elevated temperature and with a
process for making these polyurethane polyisocyanurate materials by
allowing a curable composition according to the present invention
to react at elevated temperature. Preferably the reaction is
conducted at an index of 300-100000 and most preferably of
500-10000. Preferably heat is applied in order to bring the curable
composition to a temperature above 50.degree. C. and preferably
above 80.degree. C. Then the curable composition may cure fast
(so-called snap-cure) while the temperature increases further (the
reaction is exothermic).
[0071] Before curing it, the curable composition may be fed into a
mould in order to give it a certain shape or into a cavity of an
object in order to provide the object with a polyurethane
polyisocyanurate interior or onto a surface to provide such a
surface with a polyurethane polyisocyanurate cover or it may be
used to repair an object and in particular a pipe by applying it
onto the interior and/or the exterior surface of such an object or
such a pipe (examples of such pipe repair have been described in
U.S. Pat. Nos. 4,009,063, 4,366,012 and 4,622,196) or it may be
used to bind materials as has been disclosed in WO 2007/096216.
[0072] Before the curable composition is cured, additives may be
added to it or to its constituents. Examples of additives are other
catalysts, blowing agents, surfactants, water scavengers, like
alkylorthoformate and in particular tri-isopropylorthoformate,
antimicrobial agents, fire retardants, smoke suppressants,
UV-stabilizers, colorants, plasticizers, internal mould release
agents, rheology modifiers, wetting agents, dispersing agents and
fillers.
[0073] If desired the polyurethane polyisocyanurate material
according to the present invention may be subjected to
post-curing.
[0074] The invention is illustrated with the following
examples.
EXAMPLES
Chemicals Used
[0075] Jeffamine M-600: a monofunctional polyoxyethylene
polyoxypropylene primary amine having a molecular weight of about
560 and an oxypropylene/oxyethylene ratio of about 9/1. Obtainable
from Huntsman. In these examples referred to as M-600.
[0076] Suprasec 1306 polyisocyanate ex Huntsman: 4,4'-MDI. In these
examples referred to as S1306.
[0077] Suprasec 2020 polyisocyanate: a uretonimine modified
polyisocyanate ex Huntsman, in these examples indicated as
52020.
[0078] Alcupol R1610 polyol ex Repsol indicated herein as R1610; a
polyoxypropylene triol having an average molecular weight of about
1050.
[0079] Daltocel F526 is a polyoxyethylene triol ex Huntsman; MW
about 1300. Daltocel is a trademark of the Huntsman Corporation or
an Affiliate thereof and has been registered in one or more but not
all countries. Daltocel F442 and Daltocel F555 are also polyether
polyols ex Huntsman having a nominal functionality of 3 and an
average molecular weight of about 4000 and 6000, respectively.
[0080] Voranol P400: polyol from DOW; a polyoxypropylene diol
having an average molecular weight of about 430.
[0081] Carbalink HPC: hydroxypropyl carbamate, a carboxamide
compound ex Huntsman.
[0082] Araldite DY-T epoxide ex Huntsman, triglycidylether of
trimethylolpropane, indicated herein as DY-T. Araldite and
Carbalink are trademarks of the Huntsman Corporation or an
Affiliate thereof and has been registered in one or more but not
all countries.
[0083] In none of the following examples biuret formation was
observed.
Example 1
Preparation of Polyisocyanate Compositions Comprising Lithium
Chloride and a Urea Compound
[0084] A number of moles of an amine, which was kept at 50.degree.
C., and a number of moles of a polyisocyanate 1, which was also
kept at 50.degree. C., were mixed and allowed to react for 1 hour,
while stirring, so as to form a urea compound. The reaction
temperature was kept at 80.degree. C. An amount of salt was
dissolved in an amount of ethanol while stirring.
[0085] This solution was added to the above prepared urea compound
which was still kept at 80.degree. C. Stirring was continued for
about 15 minutes. A substantial amount of ethanol was stripped off
by distillation at 85-95.degree. C. The amount of the urea/salt
mixture so obtained is given in below Table 1; together with the
amount and type of amine, polyisocyanate 1 and salt used and the
amount of ethanol used.
[0086] An amount of the so prepared urea/salt mixture (having a
temperature of about 60.degree. C.) was added to an amount of a
polyisocyanate 2 and mixed so as to prepare the polyisocyanate
composition for use with an epoxy resin composition.
[0087] In below Table 2 the amounts and types of the ingredients
used are given together with the ratio of the number of urea+biuret
equivalents per isocyanate equivalent and the number of moles of
salt per isocyanate equivalent and the number of urea+biuret
equivalents per mole of salt. Parts by weight is indicated as
pbw.
TABLE-US-00002 TABLE 1 Amine type/ Polyisocyanate 1 Salt type/
Ethanol/ Urea + salt Urea amount in type/amount amount in amount in
mixture/amount compounds moles in moles grams grams in grams A
M-600/2 S1306/1.04 LiCl/23.9 125.3 1407.6 B M600/2 S1306/1.04
LiCl/100.7 528.5 1484.4 C M-600/2 S1306/1.04 LiCl/48.6 255.0 1432.3
D M-600/2 S1306/1.04 LiCl/11.8 62.1 1396.0
TABLE-US-00003 TABLE 2 Urea compound Polyisocyanate 2 urea +
Polyisocyanate from table 1/ type/amount biuret/NCO Salt/NCO urea +
biuret/ blends amount in pbw in pbw ratio ratio salt ratio 1 A/5
S2020/95 0.0109 0.003 3.65 2 .sup. B/1.25 S2020/95 0.0027 0.003
0.91 3 C/2.5 S2020/95 0.0055 0.003 1.82 4 A/2.5 S2020/95 0.0055
0.0015 3.65 5 A/15 S2020/95 0.0328 0.009 3.65 6 .sup. A/1.25
S2020/95 0.0027 0.0007 3.65 7 D/10 S2020/95 0.0219 0.003 7.30
Preparation of Epoxy Resin Compositions According to the Present
Invention.
[0088] The carboxamide compound was added to a polyol 1 and stirred
under ambient pressure and at 120.degree. C. for 1 hour. Then a
polyol 2 was added if a second polyol was used. After cooling this
mixture to ambient conditions, Araldite DY-T was added and stirred
under ambient conditions. The amounts and types of ingredients used
have been given in Table 3, wherein also the equivalent ratios of
OH/epoxy and carboxamide/epoxy have been indicated.
Preparation of Curable Compositions and Polyisocyanurate Materials
According to the Present Invention.
[0089] The compositions of Table 2 were mixed with epoxy
compositions according to the invention (and comparative ones) for
30 seconds and placed at room temperature in order to determine the
pot-life by following the temperature profile with a thermocouple
placed in the liquid resin till the onset of the temperature rise.
The curable composition was allowed to react so as to prepare
polyurethane polyisocyanurate materials according to the present
invention. The presence of isocyanurate groups was confirmed by
Fourier Transformed InfraRed Spectroscopy (FTIRS).
[0090] The ingredients used, the amounts in parts by weight, the
number of epoxy equivalents per isocyanate equivalent and the
pot-lives are given in Table 3.
[0091] In the first column, A1 means that urea compound A (Table 1)
was used and Polyisocyanate blend 1 (Table 2), and A6 means that
urea compound A was used and polyisocyanate blend 6. For B2, 9
different experiments were conducted with urea compound B and
Polyisocyanate blend 2.
TABLE-US-00004 TABLE 3 Compositions Epoxy type/ Polyol type Polyol
type Epoxy/ OH/ Curable from table 2/ amount in 1/amount 2/amount
Carboxamide type/ NCO epoxy Carboxamide/ Pot-life compositions
amount in pbw pbw in pbw in pbw amount in pbw ratio ratio epoxy
ratio (h) A1-1* 1/100 DY-T/4 F526/2 P400/5 n.u. 0.048 0.87 0.000 5
A1-2 1/100 DY-T/4 F526/2 P400/5 urea/0.02 0.048 0.87 0.021 45 A1-3
1/100 DY-T/4 F526/2 P400/5 urea/0.04 0.048 0.87 0.042 91 A1-4 1/100
DY-T/4 F526/5 P400/5 urea/0.1 0.048 1.08 0.104 312 B2-1* 2/96.25
DY-T/4 F526/2 P400/5 n.u. 0.048 0.87 0.000 3 B2-2 2/96.25 DY-T/4
F526/2 P400/5 urea/0.02 0.048 0.87 0.021 5 B2-3 2/96.25 DY-T/4
F526/2 P400/5 urea/0.04 0.048 0.87 0.042 9 B2-4 2/96.25 DY-T/4
F526/5 P400/5 urea/0.10 0.048 1.08 0.104 89 B2-5* 2/96.25 DY-T/4
F442/5 P400/5 n.u. 0.048 0.84 0.000 5 B2-6 2/96.25 DY-T/4 F442/5
P400/5 N-methyl urea/0.010 0.048 0.84 0.004 6 B2-7 2/96.25 DY-T/4
F442/5 P400/5 N-methyl urea/0.020 0.048 0.84 0.008 7 B2-8 2/96.25
DY-T/4 F442/5 P400/5 N-methyl urea/0.050 0.048 0.84 0.021 14 B2-9
2/96.25 DY-T/4 F442/5 P400/5 N-methyl urea/0.10 0.048 0.84 0.042 35
C3-1 3/97.5 DY-T/4 F442/5 P400/5 1,1 diethyl urea/0.010 0.048 0.84
0.003 7 C3-2 3/97.5 DY-T/4 F442/5 P400/5 1,1 diethyl urea/0.020
0.048 0.84 0.005 9 C3-3 3/97.5 DY-T/4 F442/5 P400/5 1,1 diethyl
urea/0.050 0.048 0.84 0.013 14 C3-4 3/97.5 DY-T/4 F442/5 P400/5 1,1
diethyl urea/0.10 0.048 0.84 0.027 24 A1-5 1/100 DY-T/4 F526/5
R1610/10 Propionamide/0.05 0.048 1.24 0.021 90 A1-6 1/100 DY-T/4
F526/5 R1610/10 Propionamide/0.13 0.048 1.24 0.053 130 A1-7 1/100
DY-T/4 F526/5 R1610/10 Propionamide/0.25 0.048 1.24 0.107 180 A4-1
4/97.5 DY-T/4 F526/5 R1610/10 Propionamide/0.25 0.048 1.24 0.107
>138 A1-8 1/100 DY-T/4 F555/5 n.u. Tolyl urea/0.010 0.048 0.08
0.002 12 A1-9 1/100 DY-T/4 F555/5 n.u. Tolyl urea/0.05 0.048 0.08
0.010 41 A1-10 1/100 DY-T/4 R1610/15 n.u. Carbalink HPC/0.13 0.048
1.34 0.034 30 A4-2 4/97.5 DY-T/4 R1610/15 n.u. Carbalink HPC/0.13
0.048 1.34 0.034 55 A1-11 1/100 DY-T/4 F526/0.25 R1610/5
Urea/0.0063 0.048 0.46 0.007 25 A1-12 1/100 DY-T/8 F526/2.5 R1610/5
Urea/0.063 0.096 0.31 0.033 97 A1-13 1/100 DY-T/12 F526/2.5 R1610/5
Urea/0.063 0.014 0.21 0.022 40 A5-1 5/110 DY-T/4 F526/2.5 R1610/10
Urea/0.063 0.048 1.07 0.065 150 A4-3 4/97.5 DY-T/4 R1610/15 n.u.
Carbalink HPC/0.033 0.048 1.34 0.009 14 A1-15 1/100 DY-T/1.5
F526/1.5 n.u. Urea/0.015 0.018 0.28 0.042 >65 D7-1 7/105 DY-T/4
F526/1 P400/5 Urea/0.010 0.048 0.79 0.010 >65 n.u. means `not
used` * comparative example
FURTHER EXAMPLES ACCORDING TO THE INVENTION
[0092] In Table 4 the information related to a few further
experiments has been given, similar to Table 3 with the exception
that the T.sub.g of the polyisocyanurate has been given instead of
the pot-life of the curable composition. The T.sub.g was measured
by Differential Mechanical Thermo Analysis on samples having a
thickness of about 4 mm which had been cured in an open mould for 1
hour at 125.degree. C. in an oven. With further post curing the
T.sub.g could be higher.
TABLE-US-00005 TABLE 4 Compositions Epoxy type/ Polyol type Polyol
type Epoxy/ OH/ Curable from table 2/ amount in 1/amount in
2/amount in Carboxamide type/ NCO epoxy Carboxamide/ Tg (tan
.delta.) compositions amount in pbw pbw pbw pbw amount in pbw ratio
ratio epoxy ratio in .degree. C. A4-4 4/97.5 DY-T/4 F526/2.5
R1610/12.5 urea/0.13 0.048 1.29 0.130 183.9 A1-14 1/100 DY-T/4
F526/2.5 R1610/12.5 urea/0.063 0.048 1.29 0.065 192.0 A6-1 6/96.25
DY-T/4 F526/2.5 R1610/12.5 urea/0.13 0.048 1.29 0.130 186.8 A1-7
1/100 DY-T/4 F526/5 R1610/10 Propionamide/0.25 0.048 1.24 0.107
213.1 .sup.(1) A1-10 1/100 DY-T/4 R1610/15 n.u. Carbalink HPC/0.13
0.048 1.34 0.034 221.7 .sup.(1) A1-5 1/100 DY-T/4 F526/5 R1610/10
Propionamide/0.050 0.048 1.24 0.021 239.6 B2-10 2/96.25 DY-T/4
F526/5 P400/5 N-methyl urea/0.25 0.048 1.08 0.105 183.4 A1-16 1/100
DY-T/4 F526/1 R1610/14 1,1 diethyl urea/0.025 0.048 1.32 0.007
194.3 A1-17 1/100 DY-T/8 F526/1.5 R1610/13.5 Urea/0.038 0.096 0.65
0.020 197.8 .sup.(1) cured for 1 h at 150.degree. C. n.u. means
`not used`
* * * * *