U.S. patent application number 10/486486 was filed with the patent office on 2004-10-21 for polysiloxanes and their preparation.
Invention is credited to Hupfield, Peter Cheshire, Surgenor, Avril, Westall, Stephen.
Application Number | 20040210074 10/486486 |
Document ID | / |
Family ID | 9920561 |
Filed Date | 2004-10-21 |
United States Patent
Application |
20040210074 |
Kind Code |
A1 |
Hupfield, Peter Cheshire ;
et al. |
October 21, 2004 |
Polysiloxanes and their preparation
Abstract
An amino-functional polysiloxane is prepared by reacting an
aminosilane (A) which contains an aminoalkyl group and at least one
alkoxy group bonded to Si with a carboxylic acid and a
silanol-functional polysiloxane (B). The aminosilane (A) is
partially converted into its carboxylate salt which acts as a
catalyst for the siloxane condensation polymerization reaction
between (A) and (B).
Inventors: |
Hupfield, Peter Cheshire;
(Carmarthen, GB) ; Surgenor, Avril; (Cardiff,
GB) ; Westall, Stephen; (Barry, GB) |
Correspondence
Address: |
McKellar Stevens
Poseyville Professional Complex
784 South Poseyville Road
Midland
MI
48640
US
|
Family ID: |
9920561 |
Appl. No.: |
10/486486 |
Filed: |
May 13, 2004 |
PCT Filed: |
August 12, 2002 |
PCT NO: |
PCT/EP02/09821 |
Current U.S.
Class: |
556/413 |
Current CPC
Class: |
C08G 77/388 20130101;
C08L 83/04 20130101; C08K 5/09 20130101; C08K 5/544 20130101; C08G
77/08 20130101; C08L 83/04 20130101; C08G 77/16 20130101 |
Class at
Publication: |
556/413 |
International
Class: |
C07F 007/10 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 17, 2001 |
GB |
012005813 |
Claims
What is claimed is:
1. A process for the preparation of an amino-functional
polysiloxane comprising reacting an aminosilane (A) which contains
an aminoalkyl group and at least one alkoxy group bonded to Si with
a carboxylic acid (C) and a silanol-functional polysiloxane (B),
the amount of carboxylic acid (C) being such that the molar ratio
of carboxylic acid groups of (C) to amino groups of aminosilane (A)
is less than 1:1 and the amount of silanol-functional polysiloxane
(B) being such that the molar ratio of silanol groups of (B) to
Si-bonded alkoxy groups of aminosilane (A) is greater than 1:1,
whereby the aminosilane (A) is partially converted into its
carboxylate salt which acts as a catalyst for the siloxane
condensation polymerization reaction between (A) and (B).
2. A process according to claim 1, wherein the aminosilane (A) has
the formula 4wherein A and A' are each independently a linear or
branched alkylene group having 1 to 6 carbon atoms; q=0 to 4; R is
selected from the group consisting of hydrogen, an alkyl group, and
a hydroxyalkyl group having 1 to 4 carbon atoms; R' is selected
from the group consisting of an alkyl group and an alkoxyalkyl
group having 1 to 6 carbon atoms; and Y and Y' are each
independently selected from the group consisting of a group --OR',
substituted alkyl groups, substituted aryl groups, unsubstituted
alkyl groups, and unsubstituted aryl groups.
3. A process according to claim 2, wherein the group Y of
aminosilane (A) is an unsubstituted alkyl group and the group Y' is
of the formula --OR'.
4. A process according to claim 2 wherein the linkages A and A' of
aminosilane (A) are each independently a linear or branched
alkylene group having 2 to 4 carbon atoms; q=1; and R is
hydrogen.
5. A process according to claims 1 wherein the silanol-functional
polysiloxane (B) is a linear hydroxyl endblocked
polydimethylsiloxane of degree of polymerisation 4 to 1000.
6. A process according to claim 1 wherein the silanol-functional
polysiloxane (B) is a linear hydroxyl endblocked
polydiorganosiloxane containing methyl groups and 2 to 30 carbon
atom containing groups selected from the group consisting of alkyl
groups, alkenyl groups, aryl groups and aralkyl groups
7. A process according to claim 1 wherein the carboxylic acid (C)
is substituted by an electron-withdrawing moiety.
8. A process according to claim 7 wherein the carboxylic acid (C)
is selected from the group consisting of lactic acid and
fluoroalkanoic acids.
9. A process according to claim 1 wherein the carboxylic acid is an
aliphatic carboxylic acid having 6 to 20 carbon atoms.
10. A process according to claim 1 wherein the amount of carboxylic
acid (C) is such that the molar ratio of carboxylic acid groups of
(C) to amino groups of aminosilane (A) is 0.002-0.25:1
11. A process according to claim 1 wherein the amount of
silanol-functional polysiloxane (B) is such that the molar ratio of
silanol groups of (B) to Si-bonded alkoxy groups of aminosilane (A)
is 1.2-2.0:1.
12. A process according to claim 1 wherein an alcohol is co-reacted
with the aminosilane (A), carboxylic acid and silanol-functional
polysiloxane (B).
13. A process according to claim 12 wherein the alcohol is an
aliphatic alcohol having 8 to 30 carbon atoms.
14. A process according to claim 12 wherein the alcohol is selected
from the groups consisting of an ether alcohol and
hydroxy-terminated polyethers.
15. A process according to claim 16 wherein the carboxylic acid (C)
is selected from the group consisting of an alkanoic acid having 1
to 3 carbon atoms and a hydroxy-substituted carboxylic acid, and
the alcohol is selected from the group consisting of linear
alkanols having 2 to 4 carbon atoms and branched alkanols having 2
to 4 carbon atoms.
16. A process according to claim 1 wherein the condensation
reaction between (A) and (B) is carried out at a temperature in the
range 60-140.degree. C.
17. A process according to claim 1 wherein the aminosilane (A), the
carboxylic acid and the silanol-functional polysiloxane (B) are
mixed with a surfactant and water to form an emulsion, and the
condensation reaction between (A) and (B) is carried out in the
emulsion, thereby forming an emulsion of an amino-functional
polysiloxane.
18. A process according to claim 17 wherein the aminosilane (A),
carboxylic acid, silanol-functional polysiloxane (B), surfactant
and water are mixed to form an emulsion at a temperature below
50.degree. C. and the emulsion is heated to a temperature in the
range 60-140.degree. C. to effect the condensation reaction.
19. A process according to claim 1 wherein a material selected from
the group consisting of water and an alcohol endblocker is added to
the reagents after a desired reaction time in order to quench the
reaction.
20. A process according to claim 1 wherein a non-reactive
polysiloxane having a viscosity of less than 375 mPas is added to
the reagents and reaction is continued in the non-reactive
polysiloxane as diluent, thereby forming a solution of
amino-functional polysiloxane in the non-reactive polysiloxane.
21. A process according to claim 20 in which the non-reactive
polysiloxane is a cyclic polysiloxane having at least 5 silicon
atoms.
22. A process according to claim 20 in which the non-reactive
polysiloxane is a trimethylsilyl-terminated
polydimethylsiloxane.
23. An amino-functional polysiloxane of the formula 5where A, A', R
and q are defined as in claim 2; Y is selected from the group
consisting of substituted alkyl groups, unsubstituted alkyl groups,
substituted aryl groups and unsubstituted aryl groups; Z and Z',
which can be the same or different, are each selected from the
group consisting of substituted alkyl groups, unsubstituted alkyl
groups, substituted aryl groups, and unsubstituted aryl groups;
wherein in each group X is selected from the group consisting of
hydrogen, an aliphatic group and aliphatic groups containing one or
more ether linkages, at least one group X being an aliphatic group
having 8 to 30 carbon atoms; m=4-100; and n is 1-1000.
24. An amino-functional polysiloxane according to claim 23 wherein
0.2-25% of the amino groups are in carboxylate salt form.
25. A polysiloxane composition comprising a substantially linear
amino-functional polydiorganosiloxane having at least one group of
the formula R--(NH-A').sub.q-NH-A- bonded to silicon, wherein A and
A' are each independently a linear or branched alkylene group
having 1 to 6 carbon atoms; q=0-4; R is selected from the group
consisting of hydrogen, alkyl groups having 1 to 4 carbon atoms,
and hydroxyalkyl groups having 1 to 4 carbon atoms, and having a
viscosity of at least 10 Pa.s, dissolved in a non-reactive cyclic
polysiloxane having at least 5 silicon atoms and having a viscosity
of less than 375 mPa.s.
26. A polysiloxane composition according to claim 25 wherein the
content of octamethyltetrasiloxane is less than 0.25% by weight.
Description
FIELD OF THE INVENTION
[0001] This invention relates to amino-functional polysiloxanes and
to their preparation and to polysiloxane compositions containing
them.
BACKGROUND TO THE INVENTION
[0002] Amino-functional polysiloxanes are widely used in the
textile industry as fibre lubricants and as fabric softeners and
anti-wrinkle agents, and are also used in the personal care
industry as hair conditioners and in skin care compositions.
[0003] Amino-functional polysiloxanes can be prepared by mixing a
catalyst comprising both (i) at least one compound selected from
barium hydroxide and strontium hydroxide and (ii) at least one
compound selected from borates and phosphates of sodium with a
silanol terminated organopolysiloxane compound and an organosilicon
compound having at least one silicon-bonded alkoxy or alkoxyalkoxy
group and an aminoalkyl group and reacting at a temperature of at
least 50.degree. C., as described in U.S. Pat. No. 5,391,675. This
process is effective in preparing the amino-functional polysiloxane
but requires an intensive filtration step to remove catalyst
residues. Residual barium is often present in materials made via
this route due to complexation with amine functionality. This may
be detrimental in certain applications.
[0004] U.S. Pat No. 5,344,906 describes a process for the
production of an organosilicon condensation product which comprises
contacting an organosilicon compound having at least one silanol
group and wherein the silicon-bonded organic substituents can be
hydrocarbon groups optionally substituted by amino, halogen,
mercapto, hydroxyl, amido or ester substituents, with a quaternary
ammonium phosphate, borate, carbonate or silicate.
[0005] U.S. Pat No. 4,633,002 describes a process for the
preparation of an aminofunctional organosilicone compound
comprising reacting a silanol-terminated organosilicone compound
with an aminofunctional silane compound in the presence of a
catalytic amount of an organometallic compound.
[0006] WO-A-99/06486 and U.S. Pat. No. 6,284,860 describe
preparation of amino-functional polysiloxanes by reacting an
organopolysiloxane with OH end groups with an alkoxysilane which
contains at least one secondary or tertiary amine group in the
presence of a Bronstedt or Lewis acid. The Bronstedt or Lewis acid,
which is preferably an acidic phosphoric ester, but can be an
inorganic acid or a sulphonic or carboxylic acid, is used in
equivalent amount or a slight excess based on OH groups of the
OH-terminated organopolysiloxane, and the alkoxysilane is added in
stoichiometric excess based on the OH-terminated
organopolysiloxane.
SUMMARY OF THE INVENTION
[0007] A process according to the present invention for the
preparation of an amino-functional polysiloxane comprises reacting
an aminosilane (A) which contains an aminoalkyl group and at least
one alkoxy group bonded to Si with a carboxylic acid and a
silanol-functional polysiloxane (B), the amount of carboxylic acid
(C) being such that the molar ratio of carboxylic acid groups of
(C) to amino groups of aminosilane (A) is less than 1:1 and the
amount of silanol-functional polysiloxane (B) being such that the
molar ratio of silanol groups of (B) to Si-bonded alkoxy groups of
aminosilane (A) is greater than 1, whereby the aminosilane (A) is
at least partially converted into its carboxylate salt which acts
as a catalyst for the siloxane condensation polymerization reaction
between (A) and (B).
[0008] The process of the invention has the advantage that the
amino-functional polysiloxane reaction product does not contain
unwanted catalyst residues. The amine carboxylate salt which acts
as catalyst is incorporated in the amino-functional polysiloxane as
amine units which are in carboxylate salt form. The amine
carboxylate salt is an excellent catalyst for the reaction between
SiOH groups and Si-bonded alkoxy groups, and is also a good
catalyst for the siloxane chain extending reaction of SiOH groups
with SiOH groups. The amino-functional polysiloxane reaction
product does not require filtration, nor does it require heat
treatment to decompose the ammonium salt catalyst, which has the
risk of generating trialkylamine odour in the product. The
amino-functional polysiloxane can be prepared as a clear liquid
reaction product which is ready for use in many applications.
DETAILED DESCRIPTION OF THE INVENTION
[0009] The aminosilane (A) contains an aminoalkyl group and at
least one alkoxy group bonded to Si. The aminoalkyl group is
preferably of the formula R-(NH-A').sub.q-NH-A- wherein A and A'
are each independently a linear or branched alkylene group having 1
to 6 carbon atoms and optionally containing an ether linkage;
q=0-4; R is hydrogen or an alkyl or hydroxyalkyl group having 1 to
4 carbon atoms. Most preferably R is hydrogen; q=0 or 1; and A and
A' (if present) each contain 2 to 4 carbon atoms. Examples of
preferred aminoalkyl groups include --(CH.sub.2).sub.3NH.sub.2,
--(CH.sub.2).sub.4NH.sub.2,
--(CH.sub.2).sub.3NH(CH.sub.2).sub.2NH.sub.2,
--CH.sub.2CH(CH.sub.3)CH.su- b.2NH(CH.sub.2).sub.2NH.sub.2,
--(CH.sub.2).sub.3NHCH.sub.2CH.sub.2NH(CH.s- ub.2).sub.2NH.sub.2,
--CH.sub.2CH(CH.sub.3)CH.sub.2NH(CH.sub.2)3NH.sub.2,
--(CH.sub.2).sub.3NH(CH.sub.2).sub.4NH.sub.2 and
--(CH.sub.2).sub.3O(CH.s- ub.2).sub.2NH.sub.2. The alkoxy group
bonded to Si can contain an unreactive substituent or linkage such
as an ether linkage. The aminosilane (A) preferably has the formula
1
[0010] wherein A, A', q and R are defined as above; R' is an alkyl
or alkoxyalkyl group having 1 to 6 carbon atoms, for example,
methyl, ethyl, butyl or methoxyethyl; and Y and Y' are each
independently a group --OR' or an optionally substituted alkyl or
aryl group. Most preferably, for the preparation of linear
polydiorganosiloxanes, the group Y of aminosilane (A) is an
unsubstituted alkyl group such as methyl and the group Y' is of the
formula --OR', preferably methoxy or ethoxy. Examples of preferred
aminosilanes (A) are aminoethyl-aminoisobutyl methyl dimethoxy
silane (CH.sub.3O).sub.2(CH.sub.3)Si--CH.sub.2CH(CH.sub.3)CH.su-
b.2NH(CH.sub.2).sub.2NH.sub.2 and aminopropyl methyl diethoxy
silane
(C.sub.2H.sub.5O).sub.2(CH.sub.3)Si--(CH.sub.2).sub.3NH.sub.2.
[0011] The silanol-functional polysiloxane (B) is preferably a
linear hydroxyl-tipped polydiorganosiloxane. It can for example be
a linear hydroxyl-tipped polydimethylsiloxane, preferably a liquid
polydimethylsiloxane of degree of polymerisation 4-1000, most
preferably 10-100. Alternatively the polysiloxane (B) can contain
2-30C alkyl, for example, ethyl, propyl, pentyl or hexyl,
substituted alkyl, for example fluoroalkyl such as
3,3,3-trifluoropropyl, or alkenyl, for example vinyl, allyl or
hexenyl, groups or aryl, for example phenyl, or aralkyl, for
example 2-phenylpropyl, groups bonded to Si. Such groups may for
example be present as --Si(CH.sub.3)R"--O-- units, where R" is
2-30C alkyl or alkenyl, aryl or aralkyl, or as --Si(R").sub.2--O--
units. Preferably at least 80% of the total silicon-bonded
substituents are methyl groups.
[0012] The amount of silanol-functional polysiloxane (B) used is
sufficient that the molar ratio of silanol groups of (B) to
Si-bonded alkoxy groups of aminosilane (A) is greater than 1:1.
This ensures that chain extension polymerization takes place,
rather than merely capping of the silanol-functional polysiloxane
(B) by the amino-functional alkoxysilane (A). The molar ratio of
silanol groups of (B) to Si-bonded alkoxy groups of aminosilane (A)
is preferably in the range (1.2-2.0:1?).
[0013] The carboxylic acid used in the reaction, which reacts with
the aminosilane (A) to form a carboxylate salt catalyst, can be
chosen from a wide range of carboxylic acids, although the choice
of carboxylic acid can affect the physical form of the
amino-functional polysiloxane reaction product. The carboxylic acid
can for example be an aliphatic carboxylic acid having 1 or 2 up to
20 carbon atoms. We have found that aliphatic carboxylic acids
having at least 4 carbon atoms have the advantage of producing a
clear liquid reaction product. The use of aliphatic carboxylic
acids having 6 to 20, particularly 8 to 18 carbon atoms, for
example octanoic, decanoic or lauric acid, to produce a clear
reaction product is one preferred embodiment of the invention.
Aliphatic carboxylic acids having 1 to 3 carbon atoms, for example
acetic or propionic acid, or carboxylic acids substituted by a
hydrophilic group such as hydroxyl, for example lactic acid, can be
used but may form a hazy amino-functional polysiloxane reaction
product in the absence of any co-solvent. Carboxylic acids
substituted by an electron-withdrawing moiety, for example halogen
such as fluorine or chlorine or a hydroxyl group, may be preferred
since amine carboxylate catalysts formed from these acids yield
products with considerably reduced odour. Examples of such acids
substituted by an electron-withdrawing moiety are lactic acid and
fluoroalkanoic acids such as fluoroacetic acid or
4,4,4-trifluorobutanoic acid.
[0014] The carboxylic acid is preferably used at 0.05-5,
particularly 0.1 or 0.2 up to 1.0 or 2.0,% by weight based on the
aminosilane (A). At this level of addition the molar ratio of
carboxylic acid groups of (C) to amino groups of aminosilane (A) is
less than 1:1, and is generally in the range 0.002-0.25:1.
Accordingly, only a minor proportion of the amino groups of the
aminosilane (A), for example 0.2-25% of the amino groups, are in
carboxylate salt form.
[0015] In one preferred process according to the invention, an
alcohol is co-reacted with the aminosilane (A), carboxylic acid and
silanol-functional polysiloxane (B). The alcohol tends to become
incorporated in the amino-functional polysiloxane as an
end-blocking alkoxy group. The reaction between the alcohol group
and Si--OH groups is much slower than that between Si-alkoxy groups
and Si--OH groups, but is sufficiently fast that the alcohol acts
as a modifier of molecular weight. In the absence of an alcohol or
any other chain-stopping reagent, high molecular weight
hydroxyl-tipped amino-functional polysiloxanes are produced. The
alcohol can be an aliphatic alcohol having 8 to 30 carbon atoms,
for example n-octanol, n-decanol, octadecanol, cetyl alcohol or a
commercial mixture of linear and branched 12-16C alcohols. Such
high molecular weight aliphatic alcohols are preferred when
producing a clear liquid reaction product using an aliphatic
carboxylic acid having 6 to 20 carbon atoms. The alcohol can
alternatively be an ether alcohol, for example 2-methoxypropanol or
2-butoxyethanol or a hydroxy-terminated polyether, for example a
polyethoxylated fatty alcohol or a polypropylene glycol monoether.
Where the carboxylic acid reacted with the aminosilane (A) is an
alkanoic acid having 1 to 3 carbon atoms or a hydroxy-substituted
carboxylic acid, the alcohol can advantageously be a linear or
branched alkanol having 2 to 4 carbon atoms, particularly a
branched alcohol such as isopropanol or isobutanol. The 2-4C
alcohol acts as a cosolvent allowing the formation of a clear
liquid amino-functional polysiloxane reaction product.
[0016] The reaction between the aminosilane (A), carboxylic acid
and silanol-functional polysiloxane (B) can in general be carried
out at any temperature in the range 0-200.degree. C. Temperatures
of at least 50.degree. C. are preferred, most preferably from
60.degree. C. up to 120 or 140.degree. C. Such elevated
temperatures are particularly preferred for reactions in which the
aminosilane (A) has only two alkoxy groups bonded to Si, since the
initial reaction of the aminosilane with the silanol-functional
polysiloxane (B) forms a polysiloxane (B) terminated with a single
somewhat hindered Si-bonded alkoxy group. The reaction can in
general be carried out at pressures in the range from 5 mbar up to
5 bar, for example at ambient pressure; it is frequently preferred
that at least the later part of the reaction is carried out under
reduced pressure, for example 10 to 400 mbar, particularly if there
is a need to promote removal of volatile by-product (such as
methanol or ethanol evolved from the amino-functional alkoxysilane)
from the reaction system.
[0017] The reaction between the aminosilane (A), carboxylic acid
and silanol-functional polysiloxane (B) can conveniently be carried
out undiluted in the liquid phase, since the polysiloxane (B)
generally has a low enough viscosity to permit ready reaction. The
reaction can alternatively be carried out in solution, dispersion
or emulsion. Reaction in emulsion may be preferred if the
aminosiloxane product is to be used in emulsion; textile treating
agents such as fibre lubricants, softening agents and anti-wrinkle
agents are often applied from emulsion.
[0018] In one preferred process, the aminosilane (A), the
carboxylic acid and the silanol-functional polysiloxane (B) are
mixed with a surfactant and water to form an emulsion, and the
condensation reaction between (A) and (B) is carried out in the
emulsion, thereby forming an emulsion of an amino-functional
polysiloxane. The surfactant can for example be a nonionic, anionic
or cationic surfactant, for example an ethoxylated alcohol or
phenol nonionic surfactant. The amount of surfactant added can for
example be at least 0.2% based on the total weight of
silanol-functional polysiloxane (B) and aminosilane (A), preferably
at least 0.5%, for example from 2% up to 10 or 20%. Water is
preferably added in two stages. The aminosilane (A), the carboxylic
acid and the silanol-functional polysiloxane (B) are first mixed
with a surfactant and a small amount of water to form a viscous oil
in water emulsion ("thick phase"). The amount of water added at
this stage is generally at least 0.5% based on the total weight of
silanol-functional polysiloxane (B) and aminosilane (A), preferably
at least 1 % up to 10 or 20%. Further water can subsequently be
added, for example from 20 or 30% up to 100 or 200%, to form a
diluted emulsion of suitable viscosity for carrying out the
condensation reaction between (A) and (B). In general it is
preferred that the aminosilane (A), carboxylic acid,
silanol-functional polysiloxane (B), surfactant and water are mixed
to from an emulsion at a low temperature, generally below
50.degree. C., for example ambient temperature, and the emulsion is
heated to a temperature in the range 50-200.degree. C., preferably
60-140.degree. C., to effect the condensation reaction.
[0019] The emulsion of amino-functional polysiloxane produced is
generally of low particle size, for example less than 500 nm and
frequently less than 300 nm. If the mixture of aminosilane (A),
carboxylic acid, silanol-functional polysiloxane (B), surfactant
and water are acidified to a pH below 4, for example in the range 2
to 4 and preferably about pH3, it may be possible to form a
microemulsion, that is an emulsion of particle size below 100 nm,
for example 5 to 50 nm, which forms without need for vigorous
mixing. Such a low pH can be achieved by use of a carboxylic acid
of low pKa and/or by use of an acid-functional surfactant of low
pKa.
[0020] The time of reaction can for example be from 10 minutes up
to 24 hours. The reaction can be quenched after a desired time by
adding water or an alcohol endblocker to the reagents, although
quenching is not necessary. The alcohol endblocker can be selected
from the alcohols described above. The reaction can be
substantially slowed by removal of heat and if a modifier of
molecular weight such as an alcohol is present an equilibrium will
be reached. If water quenching is used, the product is a dispersion
or emulsion in which the amino-functional polysiloxane is generally
stably dispersed.
[0021] Because the amine carboxylate is a highly selective catalyst
for the reaction between Si--OH and Si-alkoxy and does not catalyse
chain scission and equilibration of Si--O--Si bonds, the
amino-functional polysiloxane produced has a more regular structure
than amino-functional polysiloxanes produced by known methods. The
amino-functional polysiloxane produced according to the invention
has the formula 2
[0022] where A, A', R and q are defined as above; Y is an
optionally substituted alkyl or aryl group; Z and Z', which can be
the same or different, are each an optionally substituted alkyl,
aryl or aralkyl group; X is hydrogen or an aliphatic group
optionally containing one or more ether linkages; m is for example
4-1000; and n is for example 1-1000, preferably 2-100. Most
preferably Y, Z and Z' are all methyl groups. The majority, and
usually at least 90%, of the 3
[0023] units in the amino-functional polymer retain the chain
length m of the silanol-functional polysiloxane (B). Where an
alcohol is co-reacted with the aminosilane (A), carboxylic acid and
silanol-functional polysiloxane (B), at least one, and usually
both, the groups X are generally derived from the alcohol. For
example, if the alcohol is an aliphatic alcohol having 8 to 30
carbon atoms, each group X in the amino-functional polysiloxane is
usually an aliphatic group having 8 to 30 carbon atoms.
[0024] The reaction between the aminosilane (A), carboxylic acid
and silanol-functional polysiloxane (B) can if desired be carried
out in the presence of a liquid organic or silicone non-reactive
diluent. A preferred diluent is a non-reactive polysiloxane having
a viscosity of less than 375 mPas, for example 5 to 100 mPa.s.
Examples of such polysiloxanes include hexamethyldisiloxane,
octamethyltrisiloxane, decamethyltetrasiloxane,
dodecamethylpentasiloxane, tetradecamethylhexasiloxane or
hexadecamethylheptasiloxane, octamethylcyclotetrasiloxane,
decamethylcyclopentasiloxane or dodecamethylcyclohexasiloxane,
heptamethyl-3-{(trimethylsilyl)oxy}-trisil- oxane (M.sub.3T),
hexamethyl-3,3,bis{(trimethylsilyl)oxy} trisiloxane (M.sub.4Q) or
pentamethyl {(trimethylsilyl)oxy} cyclotrisiloxane, or a
non-reactive, for example trimethylsilyl-terminated,
polydimethylsiloxane. Cyclic polysiloxanes having at least 5
silicon atoms, especially decamethylcyclopentasiloxane (D5), are
particularly preferred. For skin contact uses, it is sometimes
preferred to avoid the presence of octamethylcyclotetrasiloxane
(D4). The process of the present invention has the advantage that
the amine carboxylate is a highly selective catalyst for the
reaction between Si--OH and Si-alkoxy and does not catalyse chain
scission and equilibration of Si--O--Si bonds. Thus the reaction
can be carried out in a non-reactive siloxane such as D5 or a
trimethylsilyl-terminated, polydimethylsiloxane without formation
of any cyclotetrasiloxane by-product.
[0025] The liquid organic or silicone non-reactive diluent can be
present from the start of the reaction or can be added during the
reaction. Use of the non-reactive diluent allows the production of
easily handled compositions containing amino-functional
polysiloxanes of high molecular weight and high viscosity.
Amino-functional polysiloxanes of viscosity above 10 Pa.s,
preferably above 20 Pa.s, and up to 100 Pa.s or more can be
prepared as solutions or dispersions of viscosity suitable for
application in textile and personal care. Solutions of such high
viscosity amino-functional polysiloxanes in a non-reactive cyclic
polysiloxane having at least 5 silicon atoms and having a viscosity
of less than 375 mPa.s. are new and useful compositions. Where the
non-reactive diluent is a silicone, the product is generally a
solution of the amino-functional polysiloxane. These high viscosity
amino-functional polysiloxanes are particularly effective in
conditioning of hair and as fibre lubricants.
[0026] When producing high molecular weight amino-functional
polysiloxanes, it may be preferred to remove some reagent during
the later stages of preparation. For example, the aminosilane (A),
carboxylic acid and silanol-functional polysiloxane (B) can
initially be reacted in the presence of an alcohol which acts as a
chain terminating agent. A silicone non-reactive diluent can be
added during the reaction. The reaction can then be continued to
increase the chain length of the amino-functional polysiloxane.
Such continued reaction can for example be at increased temperature
and/or reduced pressure to promote removal of the alcohol. The
amount of liquid organic or silicone non-reactive diluent present
can for example be from 10 to 2000%, preferably 20 to 500% by
weight based on the total weight of aminosilane (A) and
silanol-functional polysiloxane (B). The resulting solution of
amino-functional polysiloxane in non-reactive diluent can be
further diluted for use if required.
[0027] The polysiloxane composition product, comprising a
substantially linear amino-functional polydiorganosiloxane having
at least one group of the formula R--(NH-A').sub.q-NH-A- bonded to
silicon, where A, A', R and q are defined as in Claim 2, and having
a viscosity of at least 10 Pa.s, dissolved in a non-reactive
polysiloxane having a viscosity of less than 375 mPa.s., is a
valuable product for use in hair conditioning or textile treatment.
The weight ratio of amino-functional polysiloxane to non-reactive
polysiloxane is preferably from 10:1 to 1:50. If no D4 is used in
the production of the composition, the D4 content of the
composition is generally less than 0.25% by weight of the silicone
materials present, usually less than 0.1% and frequently less than
0.01%.
[0028] The amino-functional polydiorganosiloxanes produced
according to the present invention can in general be used in the
textile industry as fibre lubricants, for example for polyester,
polyamide, acrylic, cotton or wool fibres, and as fabric softeners
and/or anti-wrinkle agents, and can be used in the personal care
industry as hair conditioners and in hair shampoos or skin care
compositions, and can also be used as ingredients of polishes or
protective coatings. In particular, when used as a conditioning
agent for hair the amino-functional polydiorganosiloxanes produced
according to the present invention make wet hair easier to comb and
dry hair softer and easier to comb without imparting greasy
characteristics to the hair.
[0029] The amino-functional polydiorganosiloxane can be used in
organic solvent solution or in aqueous solution or suspension and
can be used in free amine or in salt form, for example a chloride
salt or a carboxylate salt produced by adding carboxylic acid to
the formed amino-functional polydiorganosiloxane. Compositions
containing the amino-functional polysiloxane can contain additional
ingredients such as surfactants, thickeners, rheology modifying
additives, perfumes, waxes, emollients, cleaning agents,
lubricating oils, electrolytes, flavouring agents, biocides,
pharmaceutical or cosmetic active materials.
[0030] The amino-functional polysiloxane can be chemically modified
by reaction after it has been formed. Such modifications are known
for example in preparing textile treatment agents. It can for
example be reacted with a lactone, particularly a lactone of an
omega-hydroxy carboxylic acid having 3 to 8 ring carbon atoms such
as epsilon-caprolactone or gamma-butyrolactone, under the
conditions described in U.S. Pat. No. 5,824,814, to form a polymer
having hydroxyamide groups of the formula
--N--C(O)--(CH.sub.2).sub.x--OH, where x is 2 to 7. The
amino-functional polysiloxane can be reacted with an epoxide to
form a polymer containing beta-hydroxyamine groups, for example
with ethylene oxide to form --NH--CH.sub.2CH.sub.2OH groups as
described in U.S. Pat. No. 5,352,817 or with glycidol to form
--NH--CH(CH.sub.2OH).sub.2 groups. Alternatively it can be reacted
with an acrylate or other activated C.dbd.C bond in a Michael-type
addition, for example with hydroxyethyl acrylate to form
--NH--CH.sub.213 CH.sub.2--COO--C.sub.2H.sub.4OH groups. The
amino-functional polysiloxane can be quaternised by reaction with
an alkylating agent such as dimethyl sulphate as described in U.S.
Pat. No. 5,164,522.
EXAMPLES
[0031] The invention is illustrated by the following Examples.
Example 1
[0032] A silanol end-blocked with a viscosity of approximately 60
cP (90 g), aminoethyl-aminoisobutyl methyl dimethoxy silane (5.0
g), acetic acid (0.5 g) and a C.sub.13-C.sub.15 aliphatic alcohol
(5.1 g) were charged to a three necked flask fitted with a
condenser and thermometer, upon which they were heated to
85.degree. C. for two hours under nitrogen. The reaction mixture
was then devolatilised at 85.degree. C. under reduced pressure (100
mbar) for four hours. The resulting hazy fluid was an
amino-functional polydimethylsiloxane copolymer end capped with a
mixture of C.sub.13-C.sub.15 alkoxy, methoxy and silanol end
groups. The polymer had a viscosity of 1265 cP.
Example 2
[0033] A silanol end-blocked polydimethylsiloxane with a viscosity
of approximately 60 cP (90.2 g), aminoethyl-aminoisobutyl methyl
dimethoxy silane (5.2 g), octanoic acid (1.0 g) and a
C.sub.13-C.sub.15 aliphatic alcohol (5.1 g) were charged to a three
necked flask fitted with a condenser and thermometer, upon which
they were heated to 85.degree. C. for one hour under nitrogen. The
reaction mixture was then devolatilised at 85.degree. C. under
reduced pressure (25 mbar) for one hour. The resulting clear fluid
was an amino-functional polydimethylsiloxane copolymer end capped
with a mixture of C.sub.13-C.sub.15 alkoxy, methoxy and silanol end
groups. The polymer had a viscosity of 798 cP.
Example 3
[0034] A silanol end-blocked polydimethylsiloxane with a viscosity
of approximately 60 cP (80 g), aininoethyl-aminoisobutyl methyl
dimethoxy silane (5.2 g), octanoic acid (1.0 g) and a
C.sub.13-C.sub.15 aliphatic alcohol (15 g) were charged to a three
necked flask fitted with a condenser and thermometer, upon which
they were heated to 85.degree. C. for two hours under nitrogen. The
reaction mixture was then devolatilised at 85.degree. C. under
reduced pressure (50 mbar) for two hours. The resulting clear fluid
was an amino-functional polydimethylsiloxane copolymer end capped
with a mixture of C.sub.13-C.sub.15 alkoxy, methoxy and silanol end
groups. The polymer had a viscosity of 586 cP.
Example 4
[0035] A silanol end-blocked polydimethylsiloxane with a viscosity
of approximately 60 cP (400 g), aminoethyl-aminoisobutyl methyl
dimethoxy silane (25 g), octanoic acid (5.0 g) and a
C.sub.13-C.sub.15 aliphatic alcohol (100 g) were charged to a three
necked flask fitted with a condenser and thermometer, upon which
they were heated to 85.degree. C. for four hours under nitrogen.
The reaction mixture was then devolatilised at 85.degree. C. under
reduced pressure (50 mbar) for two hours. The resulting clear fluid
was an amino-functional polydimethylsiloxane copolymer end capped
with a mixture of C.sub.13-C.sub.15 alkoxy, methoxy and silanol end
groups. The polymer had a viscosity of 210 cP.
Example 5
[0036] A silanol end-blocked polydimethylsiloxane with a viscosity
of approximately 60 cP (95.2 g), aminoethyl-aminoisobutyl methyl
dimethoxy silane (3.2 g), octanoic acid (0.13 g) and a C
.sub.13-C.sub.15 aliphatic alcohol (1.7 g) were charged to a three
necked flask fitted with a condenser and thermometer, upon which
they were heated to 85.degree. C. for four hours under nitrogen.
The reaction mixture was then devolatilised at 85.degree. C. under
reduced pressure (100 mbar) for four hours. After four hours the
reaction was terminated to yield a clear aminofunctional siloxane
The resulting clear fluid was an amino-functional
polydimethylsiloxane copolymer end capped with a mixture of
C.sub.13-C.sub.15 alkoxy, methoxy and silanol end groups. The
polymer had a viscosity of 903 cP.
Example 6
[0037] A silanol end-blocked polydimethylsiloxane with a viscosity
of approximately 60 cP (95 g), aminoethyl-aminoisobutyl methyl
dimethoxy silane (3.3 g), heptafluorononanoic acid (0.5 g) and a
C.sub.13-C.sub.15 aliphatic alcohol (15 g) were charged to a three
necked flask fitted with a condenser and thermometer, upon which
they were heated to 85.degree. C. for three hours under nitrogen.
The reaction mixture was then devolatilised at 100.degree. C. under
reduced pressure (100 mbar) for three hours. The resulting clear
fluid was an amino-functional polydimethylsiloxane copolymer end
capped with a mixture of C.sub.13-C.sub.15 alkoxy, methoxy and
silanol end groups. The polymer had a viscosity of 1222 cP.
Example 7
[0038] A silanol end-blocked polydimethylsiloxane with a viscosity
of approximately 60 cP (259.1 g), aminoethyl-aminoisobutyl methyl
dimethoxy silane (15.5 g), octanoic acid (0.88 g) and a
C.sub.13-C.sub.15 aliphatic alcohol (18.3 g) were charged to a
three necked flask fitted with a condenser and thermometer, upon
which they were heated to 85.degree. C. for two hours under
nitrogen. The reaction mixture was then devolatilised at 85.degree.
C. under reduced pressure (20 mbar) for six hours. The resulting
clear fluid was an amino-functional polydimethylsiloxane copolymer
end capped with a mixture of C.sub.13-C.sub.15 alkoxy, methoxy and
silanol end groups. The polymer had a viscosity of 6,099 cP.
Example 8
[0039] A silanol end-blocked polydimethylsiloxane with a viscosity
of approximately 60 cP (98 g), amninoethyl-aminoisobutyl methyl
dimethoxy silane (1.99 g) and octanoic acid (0.50 g) were charged
to a three necked flask fitted with a condenser and thermometer,
upon which they were heated to 85.degree. C. for two hours under
nitrogen. The reaction mixture was then devolatilised at 85.degree.
C. under reduced pressure (20 mbar) for two hours. The resulting
clear fluid was an amino-functional polydimethylsiloxane copolymer
end capped with a mixture of methoxy and silanol end groups. The
polymer had a viscosity of 10,690 cP.
Example 9
[0040] A silanol end-blocked polydimethylsiloxane with a viscosity
of approximately 60 cP (139.8 g), aminoethyl-aminoisobutyl methyl
dimethoxy silane (7.35 g), lactic acid (0. 10 g) and a
C.sub.13-C.sub.15 aliphatic alcohol (2.59 g) were charged to a
three necked flask fitted with a condenser and thermometer, upon
which they were heated to 85.degree. C. for two hours under
nitrogen. The reaction mixture was then devolatilised at 85.degree.
C. under reduced pressure (100 mbar) for two hours. The resulting
hazy fluid was an amino-functional polydimethylsiloxane copolymer
end capped with a mixture of C.sub.13-C.sub.15 alkoxy, methoxy and
silanol end groups. The polymer had a viscosity of 1,297 cP.
Example 10
[0041] A silanol end-blocked polydimethylsiloxane with a viscosity
of approximately 60 cP (349.3 g), aminoethyl-aminoisobutyl methyl
dimethoxy silane (18.38 g), lactic acid (0.37 g) and a
C.sub.13-C.sub.15 aliphatic alcohol (7.35 g) were charged to a
three necked flask fitted with a condenser and thermometer, upon
which they were heated to 85.degree. C. for two hours under
nitrogen. The reaction mixture was then devolatilised at 85.degree.
C. under reduced pressure (140 mbar) for two hours. The resulting
hazy fluid was an amino-functional polydimethylsiloxane copolymer
end capped with a mixture of C.sub.13-C.sub.15 alkoxy, methoxy and
silanol end groups. The polymer had a viscosity of 1,779 cP.
Example 11
[0042] A silanol end-blocked polydimethylsiloxane with a viscosity
of approximately 60 cP (314.1 g), aminoethyl-aminoisobutyl methyl
dimethoxy silane (16.52 g), lactic acid (0.33 g), C.sub.13-C.sub.15
aliphatic alcohol (6.60 g) and isopropanol (37.5g) were charged to
a three necked flask fitted with a condenser and thermometer, upon
which they were heated to 80.degree. C. for two hours under
nitrogen. The reaction mixture was then devolatilised at
100.degree. C. under reduced pressure (200 mbar) for two hours. The
resulting clear fluid was an amino-functional polydimethylsiloxane
copolymer end capped with a mixture of C.sub.13-C.sub.15 alkoxy,
methoxy and silanol end groups. The polymer had a viscosity of
2,556 cP.
Example 12
[0043] A silanol end-blocked polydimethylsiloxane with a viscosity
of approximately 60 cP (139.1 g), aminoethyl-aminoisobutyl methyl
dimethoxy silane (7.35 g), lactic acid (0.25 g) and isopropanol (14
g) were charged to a three necked flask fitted with a condenser and
thermometer, upon which they were heated to 80.degree. C. for two
hours under nitrogen. The reaction mixture was then devolatilised
at 85.degree. C. under reduced pressure (100 mbar) for four hours.
The resulting clear fluid was an amino-functional
polydimethylsiloxane copolymer end capped with methoxy and silanol
end groups. The polymer had a viscosity of 5,136 cP.
Example 13
[0044] A silanol end-blocked polydimethylsiloxane with a viscosity
of approximately 60 cP (139.1 g), aminoethyl-aminoisobutyl methyl
dimethoxy silane (7.35 g), lactic acid (0.25 g) and isopropanol (14
g) were charged to a three necked flask fitted with a condenser and
thermometer, upon which they were heated to 80.degree. C. for two
hours under nitrogen. The reaction mixture was then devolatilised
at 85.degree. C. under reduced pressure (100 mbar) for eight hours.
The resulting clear fluid was an amino-functional
polydimethylsiloxane copolymer end capped with methoxy and silanol
end groups. The polymer had a viscosity of 980,051 cP.
Example 14
[0045] A silanol end-blocked polydimethylsiloxane with a viscosity
of approximately 60 cP (98.3 g), aminopropyl methyl diethoxy silane
(3.2 g) and octanoic acid (0.53 g) were charged to a three necked
flask fitted with a condenser and thermometer, upon which they were
heated to 85.degree. C. for two hours under nitrogen. The reaction
mixture was then devolatilised at 100.degree. C. under reduced
pressure (200 mbar) for three hours. The resulting clear fluid was
an amino-functional polydimethylsiloxane copolymer end capped with
methoxy and silanol end groups. The polymer had a viscosity of 1064
cP.
Example 15
[0046] A silanol end-blocked polydimethylsiloxane with a viscosity
of approximately 60 cP (139 g), aminoethyl-aminoisobutyl methyl
dimethoxy silane (7.35 g), lactic acid (0.25 g), isopropanol (14.1
g) and hexadecanol (20 g) were charged to a three necked flask
fitted with a condenser and thermometer, upon which they were
heated to 85.degree. C. for two hours under nitrogen. The reaction
mixture was then devolatilised at 85.degree. C. under reduced
pressure (100 mbar) for four hours. The resulting fluid was an
amino-functional polydimethylsiloxane copolymer end capped with C16
alkoxy, methoxy and silanol end groups. The polymer was a low
melting wax-like material with a melting point between 40.degree.
C. and 50.degree. C.
Example 16
[0047] A silanol end-blocked polydimethylsiloxane with a viscosity
of approximately 60 cP (237.6 g), aminoethyl-aminoisobutyl methyl
dimethoxy silane (5.37 g), lactic acid (0.61 g) and isopropanol (30
g) were charged to a three necked flask fitted with a condenser and
thermometer, upon which they were heated to 85.degree. C. for two
hours under nitrogen. The reaction mixture was then devolatilised
at 85.degree. C. under reduced pressure (100 mbar) for four hours,
upon which a C.sub.13-C.sub.15 aliphatic alcohol (27 g) was added.
The reaction mixture was then devolatilised at 85.degree. C. and
100 mbar for a further two hours. The resulting clear fluid was an
amino-functional polydimethylsiloxane copolymer end capped with
C.sub.13-C.sub.15 alkoxy, methoxy and silanol end groups. The
polymer had a viscosity of 1,795 cP.
Example 17
[0048] A silanol end-blocked polydimethylsiloxane with a viscosity
of approximately 60 cP (275.5 g), aminoethyl-aminoisobutyl methyl
dimethoxy silane (9.54 g), lactic acid (2.67 g), isopropanol (33 g)
and a C.sub.13-C.sub.15 aliphatic alcohol (4.95 g) were charged to
a three necked flask fitted with a condenser and thermometer, upon
which they were heated to 85.degree. C. for two hours under
nitrogen. The reaction mixture was then devolatilised at 85.degree.
C. under reduced pressure (100 mbar) for four hours, upon which
further C.sub.13-C.sub.15 aliphatic alcohol (10 g) was added. The
reaction mixture was then devolatilised at 85.degree. C. and 100
mbar for a further two hours. The resulting clear fluid was an
amino-functional polydimethylsiloxane copolymer end capped with
C.sub.13-C.sub.15 alkoxy, methoxy and silanol end groups. The
polymer had a viscosity of 1,516 cP.
Example 18
[0049] A silanol end-blocked polydimethylsiloxane with a viscosity
of approximately 60 cP (98 g), aminopropylmethyl diethoxy silane
(2.0 g) and octanoic acid (0.1 g) were charged to a three necked
flask fitted with a condenser and thermometer, upon which they were
heated to 85.degree. C. for two hours under nitrogen. The reaction
mixture was then devolatilised at 100.degree. C. under reduced
pressure (200 mbar) for four hours, upon which water (10% w/w) was
added. The resulting milky white fluid was an amino-functional
polydimethylsiloxane copolymer end capped with methoxy and silanol
end groups. The polymer had a viscosity of 1,159 cP.
Example 19
[0050] A silanol end-blocked polydimethylsiloxane with a viscosity
of approximately 60 cP (96.7 g), aminoethyl-aminoisobutyl methyl
dimethoxy silane (1.99 g), octanoic acid (0.33 g) and a
C.sub.13-C.sub.15 aliphatic alcohol (1.24 g) were charged to a
three necked flask fitted with a condenser and thermometer, upon
which they were heated to 85.degree. C. for two hours under
nitrogen. The reaction mixture was then devolatilised at 85.degree.
C. under reduced pressure (100 mbar) for five hours upon which
water (10% w/w) was added. The resulting milky white fluid was an
amino-functional polydimethylsiloxane copolymer end capped with a
mixture of C.sub.13-C.sub.15 alkoxy, methoxy and silanol end
groups. The polymer had a viscosity of 4,615 cP.
Example 20
[0051] A silanol end-blocked polydimethylsiloxane with a viscosity
of approximately 60 cP (139 g), aminoethyl-aminoisobutyl methyl
dimethoxy silane (7.35 g), propan-2-ol (14 g) and lactic acid (0.25
g) were charged to a three necked flask fitted with a condenser and
thermometer, upon which they were refluxed for two hours under
nitrogen. The propan-2-ol was then removed under reduced pressure
(100 mbar). After 1 hour, decamethylcyclopentasiloxane (146.35 g)
was added and the reaction continued at 85.degree. C./100 mbar.
After 6.5 hours the reaction was stopped. The resulting solution of
an amino-functional polydimethylsiloxane copolymer in
decamethylcyclopentasiloxane had a viscosity of 60,000 cts.
.sup.29Si NMR analysis showed no formation of
octamethylcyclotetrasiloxane.
Example 21
[0052] A silanol end-blocked polydimethylsiloxane with a viscosity
of approximately 60 cP (170 g), aminoethyl-aminoisobutyl methyl
dimethoxy silane (10.1 g) and octanoic acid (2.0 g) were charged to
a three necked flask fitted with a condenser and thermometer, upon
which they were heated to 85.degree. C. for two hours under
nitrogen. The reaction mixture was then devolatilised at 85.degree.
C. under reduced pressure (100 mbar) for four hours. The reaction
mixture was then cooled to 50.degree. C. upon which glycidol (8.0
g) was added. The reaction was held at 50.degree. C. for four hours
and then heated to 85.degree. C. and held at this temperature for a
further two hours. The resulting clear fluid was an
aminopolyol-functional polydimethylsiloxane copolymer end capped
with C.sub.13-C.sub.15 alkoxy, methoxy and silanol end groups. The
polymer had a viscosity of 25,000 cP.
Example 22
[0053] A silanol end-blocked polydimethylsiloxane with a viscosity
of approximately 60 cP (170 g), aminoethyl-aminoisobutyl methyl
dimethoxy silane (10.1 g) and octanoic acid (5.0 g) were charged to
a three necked flask fitted with a condenser and thermometer. The
reagents were allowed to stir at room temperature for two hours.
After two hours the above cold-blend (15.0 g) was mixed with
Softanol 50 (3 g) and Softanol 70 (6 g) for ten minutes after which
water (7.2 g) was added. Softanol 50 and Softanol 70 are
ethoxylated C12-14 secondary alcohol surfactants with 5 and 7
ethylene oxide groups respectively. The resulting thick phase was
stirred for a further ten minutes upon which further water was
added over the period of an hour (68.5 g). On complete addition of
the water, acetic acid was added (0.25 g) and the resulting
microemulsion heated to 85.degree. C. under reduced pressure (400
mbar) for a further six hours yielding an aminofunctional siloxane
microemulsion.
* * * * *