Photocurable silicone gel composition, and method of making the same

• US 5,182,315 A
• Filed: 11/19/1990
• Issued: 01/26/1993
• Est. Priority Date: 11/19/1990
• Status: Expired due to Fees

• Current Assignee: Loctite Corporation (Henkel AG & Co KGaA)
• Original Assignee: Loctite Corporation (Henkel AG & Co KGaA)
• Inventors: Cross, Robert P., Chu, Hsien-Kun, Crossan, David I.
• Primary Examiner(s): McCamish, Marion E.
• Assistant Examiner(s): BERMAN, SUSAN W
• Application Number:
  US07/615,186
• Time in Patent Office: 799 Days
• Field of Search: 528/31, 528/32, 528/34, 522/99, 522/172, 522/37, 522/40, 522/44, 522/46
• US Class Current: 522/37
• CPC Class Codes: C08G 77/50 by carbon linkages C08G77/485 takes precedence
• CPC Class Codes: C08L 83/14 in which at least two but not all the silicon atoms are connected by linkages other than oxygen atoms C08L83/10 takes precedence
• CPC Class Codes: C09D 183/14 in which at least two but not all the silicon atoms are connected by linkages other than oxygen atoms C09D183/10 takes precedence
• CPC Class Codes: C09K 2003/1062 UV-curable materials
• CPC Class Codes: C09K 2200/0247 Silica
• CPC Class Codes: C09K 2200/0625 Polyacrylic esters or derivatives thereof
• CPC Class Codes: C09K 3/1018 Macromolecular compounds having one or more carbon-to-silicon linkages

Abstract

A silicone composition comprising:

(a) a first silane of the formula: ##STR1## wherein: R₁, R₂, R₃, R₄, R₅, R₆, R₇, R₈, R₉, and R₁₀ are independently selected from hydrogen, halo, and organo radicals; and

n is an integer having a value of from 1 to 4;

(b) a second silane of the formula: ##STR2## wherein: R₁₁ and R₁₆ are non-polymerizable groups and are independently selected from halo and organo radicals;

R₁₂, R₁₃, R₁₄, and R₁₅ are independently selected from hydrogen, halo, and organo radicals; and

n is an integer having a value of from 1 to 4; and

(c) a polysiloxane having at least two functional groups per molecule with which said first and second silanes are cappingly reactive;

wherein: (1) the first and second silanes together are provided in sufficient quantity relative to the polysiloxane to react with substantially all of the cappingly reactive functional groups of the polysiloxane; and (2) the first silane constitutes from about 50% to about 98% by weight of the total weight of the first and second silanes.

Claims

1. A silicone composition, comprising:

(a) a first silane of the formula;

##STR22## wherein;

R₁, R₂, R₃, R₄, R₅, R₆, R₇, R₈, R₉, and R₁₀ are independently selected from hydrogen, halo, and organo radicals; and

n is an integer having a value of from 1 to 4;

(b) a second silane of the formula;

##STR23## wherein;

R₁₁ and R₁₆ are non-polymerizable groups and are independently selected from halo and organo radicals;

R₁₂, R₁₃, R₁₄, and R₁₅ are independently selected from hydrogen, halo, and organo radicals; and

n is an integer having a value of from 1 to 4; and

(c) a polysiloxane having at least two functional groups per molecule with which said first and second silanes are cappingly and non-hydrolyzingly reactive;

wherein;

(1) the first and second silanes together are provided in sufficient quantity relative to said polysilxane to non-hydrolyzingly react with substantially all of the cappingly reactive functional groups of the polysiloxane, and (2) the first silane constitutes from about 50% to about 98% by weight of the total weight of the first and second silanes.

2. A composition according to claim 1, wherein the first silane constitutes from about 70% to about 90% by weight of the total weight of the first and second silanes.

3. A composition according to claim 1, wherein the first and second silanes together are provided in sufficient quantity relative to the polysiloxane to react essentially completely with the cappingly reactive functional groups of the polysiloxane.

4. A composition according to claim 1, wherein R₁₁ and R₁₆ are independently selected from hydrocarbyl, fluorocarbyl, and fluorohydrocarbyl.

5. A composition according to claim 1, wherein R₁₁ and R₁₆ are independently selected from organo groups containing from 1 to 8 carbon atoms.

6. A composition according to claim 1, wherein R₁₁ and R₁₆ are independently selected from C₁ -C₈ alkyl.

7. A composition according to claim 1, wherein the second silane contains at least two acetoxy functional groups.

8. A composition according to claim 1, wherein R₁, R₂, R₃, R₄, R₅, R₈, R₉, and R₁₀ are independently selected from hydrogen and C₁ -C₈ alkyl.

9. A composition according to claim 1, wherein R₆ and R₇ are independently selected from hydrogen, phenyl, and C₁ -C₈ alkyl.

10. A composition according to claim 1, wherein R₁, R₂, R₉, and R₁₀ are hydrogen;

R₄ and R₅ are each methyl;

R₆ and R₇ are independently selected from hydrogen, methyl, and phenyl; and

R₃ and R₈ are independently selected from hydrogen and methyl.

11. A composition according to claim 1, wherein R₁₁ and R₁₆ are independently selected from C₁ -C₈ alkyl and phenyl.

12. A composition according to claim 1, wherein R₁₄ and R₁₅ are independently selected from the group consisting of hydrogen, C₁ -C₈ alkyl, and phenyl.

13. A composition according to claim 1, wherein R₁₁ and R₁₆ are each methyl.

14. A composition according to claim 1, wherein n for each of said first and second silanes is 1.

15. A composition according to claim 1, additionally comprising

(d) a third silane of the formula:

##STR24## wherein;

R₄, R₅, R₆, and R₇ and n have the same meanings as in the first silane formula;

one of the G and X groups is ##STR25## wherein;

R₁, R₂, and R₃ have the same means as in the first silane formula, and the other of the G and X groups is R₁₁ having the same means as in the second silane formula.

16. A composition according to claim 1, wherein said polysiloxane functional groups comprise silicon-bonded functional groups including labile hydrogen constituents.

17. A composition according to claim 1, wherein said polysiloxane functional groups comprise functionality selected from the group consisting of:

--OH;

--N(R'"'"')₂, wherein each of the R'"'"' substituents is independently selected form hydrogen and organo groups, with the proviso that at least one R'"'"' substituent is hydrogen;

--SH;

--SO₃ H; and

##STR26## wherein each of the R" and R"'"'"'substituents is independently selected from hydrogen and organo groups;

with the proviso that said silicone functionality is ##STR27## only when the first and second silanes are present with residual acrylic acid groups deriving from the synthesis of at least one of the first and second silanes.

18. A composition according to claim 1, wherein said polysiloxane having at least two functional groups per molecule with which said first and second silanes are cappingly and non-hydrolyzingly reactive, comprises a linear polydiorganosiloxane.

19. A composition according to claim 1, wherein said polysiloxane functional groups comprise a terminal reactive functional group.

20. A composition according to claim 1, wherein said polysiloxane comprises a linear silicone with hydroxy functional groups at its termini.

21. A composition according to claim 20, wherein said linear silicone has a weight average molecular weight of from about 700 to about 300,000.

22. A composition according to claim 1, wherein the second silane comprises acetoxymethyldimethylacetoxysilane.

23. A composition according to claim 1, wherein said first silane has the formula:

##STR28## wherein R₁₇ and R₁₈ are independently selected from H and methyl.

24. A composition according to claim 1, wherein the equivalents ratio of acryloxy functionality of said first silane to polysiloxane functional groups non-hydrolyzingly reactive with said first silane is less than 1.0.

25. A photocured silicone material produced by curing a composition according to claim 1, under conditions curingly effective therefor.

26. A silicone composition, comprising:

a polysiloxane having at least two acryloxy-reactive functional sites per molecule; and

a composition comprising capping species non-hydrolyzingly reactive with said functional sites of said polysiloxane, including acryloxy functionality and non-polymerizable functionality, which when non-hydrolyzingly reacted with said polysiloxane functional sites are cappingly effective therefor to provide acryloxy functionality and non-polymerizable functionality on said polysiloxane, such that the acryloxy functionality on the capped polysiloxane functionalizes from about 50% to about 98% of the reactive functional sites on the polysiloxane, and the non-polymerizable functionality functionalizes the remaining reactive functional sites on the polysiloxane.

27. A composition according to claim 26, wherein the capping composition comprises a silane compound having acryloxy and non-polymerizable functionality in the same molecule.

28. A photocurable polysiloxane composition, comprising the non-hydrolysis reaction product of the composition of claim 26.

29. A photocured silicone material produced by curing the composition of claim 28, under conditions curingly effective therefor.

30. A method of capping a silicone having active hydrogen-containing functionality with (i) acrylic functionality to render the silicone photocurable in character, and with (ii) non-reactive functionality, comprising non-hydrolyzingly reacting the active hydrogen-containing functionality of said silicone with:

(A) a silyl diacrylate compound of the formula;

##STR29## wherein;

R₁ R₂, R₃, R₄, R₅ R₆, R₇, R₈ and R₁₀ are independently selected from hydrogen, halo, and organo radicals; and

n is an integer having a value of from 1 to 4; and

(B) a silane compound of the formula;

##STR30## wherein;

R₁₁ and R₁₆ are non-polymerizable groups and are independently selected from halo and organo radicals; and

R₁₂, R₁₃, R₁₄, are independently selected from hydrogen, halo, and organo radicals,

to yield a capped silicone having from about 50% to about 98% of the active hydrogen-containing functionality of the silicone capped with acryloxy functionality deriving from said silyl diacrylate compound, and the remainder of the active hydrogen-containing functionality of the silicone capped with capping moieties derived from said silane compound.

31. A method according to claim 30, wherein said silicone cappable functionality comprises a functionality selected form the group consisting of:

--OH;

--N(R'"'"')₂, wherein each of the R'"'"' substituents is independently selected from hydrogen and organo groups, with the proviso that at least one R'"'"' substituent is hydrogen;

--SH; and

--SO₃ H.

32. A method according to claim 30, wherein said silane diacrylate has the formula:

##STR31## wherein R₁₇ and R₁₈ are independently selected form H and methyl.

33. A method according to claim 30, further comprising forming a silicone composition which is photocurable to a gel, comprising mixing the capped silicone with a photoinitiator.

34. A method according to claim 33, wherein the photoinitiator is selected from the group consisting of benzophenone, benzoin, acetophenone, benzil, and substituted forms thereof, and mixtures thereof.

35. A method according to claim 33, further comprising exposing said photocurable silicone gel composition to radiation curingly effective therefor, to yield a photocured silicone composition.

36. A method according to claim 35, wherein said radiation comprises ultraviolet radiation.