Crosslinked emulsions of pre-formed silicon modified organic polymers

• US 5,840,800 A
• Filed: 11/02/1995
• Issued: 11/24/1998
• Est. Priority Date: 11/02/1995
• Status: Expired due to Term

• Current Assignee: Dow Corning Corporation (Dow, Inc.)
• Original Assignee: Dow Corning Corporation (Dow, Inc.)
• Inventors: Tselepis, Arthur James, Wolf, Andreas Thomas Franz, Joffre, Eric Jude
• Primary Examiner(s): Marquis, Melvyn I.
• Application Number:
  US08/552,162
• Time in Patent Office: 1,118 Days
• Field of Search: 524/837, 524/806, 525/100, 525/103, 525/104, 525/105, 525/106, 525/474, 525/537
• US Class Current: 524/806
• CPC Class Codes: C08G 65/336 containing silicon
• CPC Class Codes: C08J 2300/108 containing hydrolysable silane groups
• CPC Class Codes: C08J 3/03 in aqueous media
• CPC Class Codes: C08L 101/10 containing hydrolysable silane groups

Abstract

A crosslinked polymer dispersion comprising a preformed polymer, selected from the group consisting of silicon modified organic polymers, mixtures of silicon modified organic polymers, mixtures of silicon modified organic polymer(s) with regular organic polymers, mixtures of silicon modified organic polymer(s) with siloxane polymers, mixtures of above polymers, and mixtures of above polymer(s) with organic plasticizers or solvents.

Claims

1. A method of forming a aqueous dispersion of a crosslinked silicon-modified organic polymer comprising:

forming a premixture comprising;

a) 100 weight parts of silicon-modified organic polymer,

b) 0.5 to 10 weight parts surfactant and

c) 0.5 to 1000 weight parts water;

agitating the premixture to form an emulsion; and

facilitating the crosslinking of the silicon-modified organic polymer in the emulsion;

wherein, the silicon-modified organic polymer is an organic polymer having a viscosity of 5 to 500 Pa.s, a glass transition temperature of less than 20°

C., and 1 to 5 substitutents represented by the formula;

space="preserve" listing-type="equation">--Y--(X.sub.b R.sup.1.sub.2-b SiO).sub.m SiX.sub.a R.sup.1.sub.3-a

wherein R¹ is the same or different alkyl, alkenyl, aryl, or aralkyl group having 1 to 20 carbon atoms, or a triorganosiloxy group represented by the formula R²₃ SiO--, where R² individually is a monovalent hydrocarbon group having from 1 to 20 carbon atoms,

X is the same or different hydroxyl group, condensable group or hydrolyzable group;

Y is a divalent group which forms hydrolytically stable bonds to the organic polymer and to a silicon atom of the substituent;

a is an integer from 0 to 3,

b is an integer from 0 to 2 with the proviso that if a is 0 then b is 1 or 2 in at least one siloxane unit of the substituent and m is an integer of from 0 to 19 with the proviso that if m is 0 then a is 1, 2, or 3.

2. The method of claim 1, wherein the crosslinking of the silicon-modified organic polymer is facilitated by adding up to 5 weight parts catalyst to the emulsion.

3. The method of claim 1, wherein the crosslinking of the silicon-modified organic polymer is facilitated by adding up to 50 weight parts crosslinker to the emulsion.

4. The method of claim 2, wherein the crosslinking of the silicon-modified organic polymer is facilitated by adding up to 50 weight parts crosslinker to the emulsion.

5. The method of claim 2, comprising adding a catalyst deactivator to the composition after 3 to 14 days of gestation time.

6. The method of claim 1, wherein the organic polymer is selected from the group consisting of polyether, polyester, ether-ester block co-polymer, polyurethane, polysulfide, polythioether, polythioester, polybutadiene, hydrogenated polybutadiene, styrene-butadiene co-polymer, acrylate-butadiene co-polymer, ethylene-butadiene co-polymer, vinylpyridinebutadiene co-polymer, ethylene-propylene co-polymer, ethylenevinyl acetate co-polymer, ethylene-acrylate co-polymer, polyisoprene, styrene-isoprene co-polymer, polyisobutylene, isobutylene-isoprene co-polymer, polychloroprene, styrene-chloroprene co-polymer, acrylonitrile-chloroprene co-polymer, polyacrylate, polymethacrylate, siloxane-ether block co-polymer, siloxane-olefin block co-polymer, fluoroolefin-ether co-polymer, and poly(perfluoroether).

7. The method of claim 1, wherein the silicon-modified organic polymer is crosslinked using a condensation reaction, in the presence of a condensation catalyst selected from the group consisting of organometallic compounds, amino compounds, carboxylic acids, salts of amino compounds with carboxylic or other acids, low molecular weight polyamide resins obtained by the reaction of excess of polyamines with polybasic acids, the reaction products between epoxy compounds and an excess of polyamines, and mixtures of aforesaid condensation catalysts.

8. The method of claim 3, wherein the crosslinker has on average at least one hydrolyzable or condensable group and is selected from the group consisting of

R_n SiX.sub.(4-n),

_n SiX_4-n,

R₃ SiO(SiR₂ O)_a (SiRXO)_b SiR₃,

cyclic siloxanes represented by the formula (R₂ SiO)_a (RXSiO)_b),

silsesquioxanes, containing X groups bound directly to silicon atoms,

organic oligomers, polymers or resins bearing Si--X groups bound to carbon atom(s) via Si--C or Si--Y--C bonds,

the partial hydrolysis products of the above crosslinkers;

and

mixtures of the above crosslinkers,

where;

X is the same or different hydrolyzable or condensable group individually selected from the class consisting of alkoxy, aryloxy, alkoxyalkoxy, alkoxyaryloxy, alkenoxy (--O--CR'"'"'═

CR'"'"'₂), acyloxy (O(O)CR'"'"'), oximo (O--N═

CR'"'"'₂), amino (NR'"'"'₂ or NR"), aminoxy (ONR'"'"'₂ or ONR"), amido (NR'"'"'--(CO)--R"), ureido (NR'"'"'--(CO)--NR'"'"'₂), imidato (N═

CR'"'"'₂), and isocyanato (--NCO),

R is individually selected from the group consisting of hydrogen, monovalent hydrocarbon radical and substituted hydrocarbon radicals having less than 7 carbon atoms, functionalized hydrocarbon radicals, and nitrogen compounds of the formula --N═

CR'"'"'₂ or --NR'"'"'COR'"'"' or --NR'"'"'₂ or --NR",

R'"'"' is either hydrogen or monovalent hydrocarbon or substituted hydrocarbon radical,

R" is a cycloalkyl radical,

a and b are independently either 0 or a positive integer,

n is either 0, 1, 2, or 3.

9. The method of claim 3, wherein the crosslinking is facilitated by a crosslinker and an optional catalyst, and the crosslinker is selected from the group consisting of hydroxy functional linear and cyclic siloxanes, liquid copolymers comprising SiO₂ and/or SiO_3/2 units and bearing silicon bonded hydroxyl groups, silsesquioxane containing hydroxyl groups bound directly to silicon atoms, and organic oligomers, polymers or resins having hydroxysilyl groups bound to carbon atom(s) via Si--C or Si--Y--C bonds, and the silicon modified organic polymer bears at least two X groups, wherein said X groups are the same or different hydrolyzable or condensable groups individually selected from the group consisting of alkoxy, aryloxy, alkoxyalkoxy, alkoxyaryloxy, alkenoxy, acyloxy, oximo, amino, aminoxy, amido, ureido, imidato, and isocyanato.

10. The method of claim 3, wherein the silicon modified organic polymer bears at least one X group, wherein X is the same or different hydrolyzable or condensable group individually selected from the group consisting of acyloxy, oximo, amino, aminoxy, amido, ureido, imidato, and isocyanato and wherein the cross-linker is selected from the group consisting of hydroxy functional linear and cyclic siloxanes, liquid copolymers comprising SiO₂ and/or SiO_3/2 units and bearing silicon bonded hydroxyl groups, silsesquioxane containing hydroxyl groups bound directly to silicon atoms, and organic oligomers, polymers or resins having hydroxysilyl groups bound to carbon atom(s) via Si--C or Si--Y--C bonds.

11. The method of claim 1, wherein the silicon modified organic polymer bears at least one X group, wherein X is the same or different hydrolyzable or condensable group individually selected from the group consisting of acyloxy, oximo, amino, aminoxy, amido, ureido, imidato, and isocyanato.

12. The method of claim 4, wherein the silicon modified organic polymer bears at least two X groups, the catalyst is a condensation catalyst, and the cross-linker has on average, more than two (2.0) hydrolyzable X groups;

wherein X is the same or different hydrolyzable or condensable group individually selected from the group consisting of alkoxy, aryloxy, alkoxyalkoxy, alkoxyaryloxy and alkenoxy (--O--CR'"'"'═

CR'"'"'₂) groups, wherein R'"'"' is either hydrogen or monovalent hydrocarbon or substituted hydrocarbon radical.

13. The method of claim 1, wherein the silicon modified organic polymer bears at least two X groups, and an optional condensation catalyst is present, wherein X is the same or different hydrolyzable or condensable group selected from the group consisting of alkoxy, aryloxy, alkoxyalkoxy, alkoxyaryloxy, alkenoxy, acyloxy, oximo, amino, aminoxy, amido, ureido, imidato, and isocyanato.

14. The method of claim 13, wherein a crosslinker is added bearing, on average, more than two (2.0) hydrolyzable groups.

15. The method of claim 4, wherein the silicon modified organic polymer bears at least two hydroxysilyl or alkoxysilyl groups, the catalyst is a condensation catalyst, and the cross-linker is selected from the group consisting of silica, silicate, siliconate (RSi(O^- M⁺)_n (OH)_3-n), silanolate (R₂ Si(OM)_m (OH)_2-m) (where R is monovalent hydrocarbon radical, substituted hydrocarbon radical, or functionalized hydrocarbon radical, M is selected from the group consisting of an alkali metal cation, an ammonium group, and a phosphonium group, and n is an integer or fraction having value of from 0.1 to 3, and m is an integer or fraction having a value of from 0.1 to 2), silanol functional silicone resin, and silanol functional organic resins and partial condensation products of above cross-linkers, which are not fully condensed.

16. The method of claim 4, wherein the silicon modified organic polymer bears at least two hydroxysilyl groups, the catalyst is a nucleophilic catalyst, and the crosslinker is a silane, a linear or cyclic siloxane, a silsesquioxane, an organic oligomer, polymer, or resin bearing at least two silacycloalkane group(s) --(Si(CH₂)_n), attached to the cross-linker via Si--C, Si--Y, Si--(O--Si)_n --C, or Si--(--Si)_n --Y--C bonds, wherein n is a positive integer.

17. The method of claim 2, wherein the silicon modified organic polymer, bears at least two silacycloalkane groups, the catalyst is a nucleophilic catalyst, and an optional cross-linker selected from the group consisting of hydroxy functional linear and cyclic siloxanes, liquid copolymers comprising SiO₂ and/or SiO_3/2 units and bearing silicon bonded hydroxyl groups, silsesquioxane containing hydroxyl groups bound directly to silicon atoms, and organic oligomers, polymers or resins having hydroxysilyl groups.

18. The method of claim 3, wherein the silicon modified organic polymer bears at least two hydroxysilyl groups, a condensation catalyst which is optionally present, and a cross-linker selected from the group consisting of a silane, a linear or cyclic siloxane, a silsesquioxane, an organic oligomer, polymer, and resin bearing at least two aza-silacycloalkane, cyclosilalactam, and cyclosila-urea group(s) attached to the cross-linker.

19. The method of claim 3, wherein the silicon modified organic polymer, bears at least two groups X where X is selected from the group consisting of aza-silacycloalkane, cyclosilalactam, cyclosila-urea, and other hydrolyzable and condensable groups, a condensation catalyst optionally present, and a cross-linker selected from the group consisting of hydroxy functional linear or cyclic siloxanes, liquid copolymers comprising SiO₂ and/or SiO_3/2 units and bearing silicon bonded hydroxyl groups, silsesquioxane containing hydroxyl groups bound directly to silicon atoms, and organic oligomers, polymers or resins having hydroxysilyl groups.

20. The method of claim 19, wherein a crosslinker is present and the crosslinker bears on average, more than two (2.0) hydrolyzable groups bonded to one or more silicon atoms.

21. The method of claim 2, where the catalyst is a Sn(IV) compound which is deactivated by addition of a complexing compound.

22. An aqueous dispersion comprising:

a) 100 weight parts of a crosslinked, silicon-modified organic polymer,

b) 0.5 to 10 weight parts surfactant and

c) 0.5 to 1000 weight parts water;

wherein the crosslinked, silicon-modified organic polymer is a crosslinked product of an organic polymer having a viscosity of 5 to 500 Pa.s, a glass transition temperature of less than 20°

C., and 1 to 5 substituents represented by the formula;

space="preserve" listing-type="equation">--Y--(X.sub.b R.sup.1.sub.2-b SiO).sub.m SiX.sub.a R.sup.1.sub.3-a

wherein R¹ is the same or different alkyl, alkenyl, aryl, or aralkyl group having 1 to 20 carbon atoms, or a triorganosiloxy group represented by the formula R²₃ SiO--, where R² individually is a monovalent hydrocarbon group having from 1 to 20 carbon atoms;

X is the same or different hydroxyl group, condensable group or hydrolyzable group;

Y is a divalent group which forms hydrolytically stable bonds to the organic polymer and to a silicon atom of the substituent;

a is an integer from 0 to 3;

b is an integer from 0 to 2 with the proviso that if a is 0 then b is 1 or 2 in at least one siloxane unit of the substituent and m is an integer of from 0 to 19 with the proviso that if m is 0 then a is 1, 2 or 3.

23. The crosslinked dispersion of claim 22, wherein the crosslinked dispersion includes 1 to 50 weight parts of liquid, branched methylsiloxane polymers comprising, (CH₃)₃ Si₀.5, (CH₃)₂ SiO, and CH₃ SiO₁.5, units and containing from 0.1 to 8% hydroxyl groups.

24. The crosslinked dispersion of claim 22, wherein the crosslinked dispersion includes 1 to 50 weight parts of branched methylsiloxane polymeric resins comprising, (CH₃)₃ Si₀.5, (CH₃)₂ SiO, CH₃ SiO₁.5, and SiO₂ units and containing from 0.1 to 8% hydroxyl groups.

25. The crosslinked dispersion of claim 22, wherein the crosslinked dispersion includes 1 to 10 weight parts of an organic solvent.

26. The crosslinked dispersion of claim 22, comprising up to 100 weight parts filler.

27. The crosslinked dispersion of claim 22, comprising up to 50 weight parts adhesion promoter.

28. The crosslinked dispersion of claim 22, comprising up to 50 weight parts of a shelf stabilizer.

29. The crosslinked dispersion of claim 22, comprising up to 50 weight parts of a silsesquioxane resin suspension.

30. The crosslinked dispersion of claim 22, comprising up to 10 weight parts of a catalyst deactivator.

31. The crosslinked dispersion of claim 22, which includes an amine stablizer selected from the group consisting of diethylamine, 2-amino-2-methyl-1-propanol, and tetramethylbutylguanidine.

32. The crosslinked dispersion of claim 22, wherein the surfactant is present in an amount comprising 2 to 5 weight parts.

33. The crosslinked dispersion of claim 22, wherein the water is present in an amount comprising 6 to less than 200 weight parts.

34. The crosslinked dispersion of claim 22, wherein the organic polymer is selected from the group consisting of polyether, polyester, ether-ester block co-polymer, polyurethane, polysulfide, polythioether, polythioester, polybutadiene, hydrogenated polybutadiene, styrene-butadiene co-polymer, acrylate-butadiene co-polymer, ethylene-butadiene co-polymer, vinylpyridinebutadiene co-polymer, ethylene-propylene co-polymer, ethylenevinyl acetate co-polymer, ethylene-acrylate co-polymer, polyisoprene, styrene-isoprene co-polymer, polyisobutylene, isobutylene-isoprene co-polymer, polychloroprene, styrene-chloroprene co-polymer, acrylonitrile-chloroprene co-polymer, polyacrylate, polymethacrylate, siloxane-ether block co-polymer, siloxane-olefin block co-polymer, fluoroolefin-ether co-polymer, and poly(perfluoroether).

35. The crosslinked silicon modified organic polymer dispersion of claim 22, wherein the silicon modified organic polymer bears at least one X group, wherein X is the same or different hydrolyzable or condensable group selected from the group consisting of alkoxy, aryloxy, alkoxyalkoxy, alkoxyaryloxy, alkenoxy, acyloxy, oximo, amino, aminoxy, amido, ureido, imidato, and isocyanato.

36. The crosslinked dispersion of claim 22, wherein the silicon modified organic polymer bears at least two hydroxysilyl or alkoxysilyl groups.

37. The crosslinked dispersion of claim 22, wherein the silicon modified organic polymer, bears at least two groups X where X is selected from the group consisting of aza-silacycloalkane, cyclosilalactam, cyclosila-urea, and other hydrolyzable or condensable groups.