Photocurable silicone composition, and method of making same

• US 5,348,986 A
• Filed: 01/25/1993
• Issued: 09/20/1994
• Est. Priority Date: 11/19/1990
• Status: Expired due to Term

• Current Assignee: Loctite Corporation (Henkel AG & Co KGaA)
• Original Assignee: Loctite Corporation (Henkel AG & Co KGaA)
• Inventors: Cross, Robert P., Welch, Edward K. II, Chu, Hsien-Kun, Crossan, David I.
• Primary Examiner(s): BERMAN, SUSAN W
• Application Number:
  US08/007,946
• Time in Patent Office: 603 Days
• Field of Search: 522/99, 522/37, 522/40, 522/44, 522/46, 522/81, 522/83, 524/860, 524/862, 528/32, 528/33
• 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

Photocurable silicone compositions based on capping of a silicone with a silyl diacrylate capper of the formula ##STR1## wherein: R₁, R₂, R₃, R₄, R₅, R₆, R₇, R₈, R₉, and R ₁₀ are independently selected from hydrogen, halo, and organo radicals; and n is an integer having a value of from 1 to 4.

In specific embodiments, the compositions include a polymodal-cure resin composition comprising an acryloxy-functional capped silicone, and a photocurable silicone gel composition and precursor thereof.

Claims

1. A silicone:

(i) capped, by a non-hydrolysis capping reaction, with acryloxy functional moieties of a silyl diacrylate caper of the formula;

##STR36## 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;

whereby said silicone is partially curable under radiation exposure conditions curingly effective therefor, optionally including the presence therewith of a photoinitiator, and

(ii) having additional functionality imparting to the silicone at least one partial curing modality different from the partially curingly effective radiation exposure conditions constituting a first partial curing modality therefor, or

being present with another material which is curable by curing conditions other than actinic radiation exposure curingly effective for the silicone by virtue of the acryloxy-functional moieties thereof.

2. A silicone according to claim 1, of the formula:

##STR37## wherein;

each R is independently selected from the group consisting of hydrogen, halo, and organo radicals;

each X is independently;

(i) an acryloxy-functional capping moiety derived from said silyl diacrylate capper and imparting actinic radiation exposure curability, optionally in the presence of a photoinitiator, to the silicone, or

(ii) an additional function moiety imparting to the silicone another cure modality differing form its actinic radiation exposure curability by virtue of acryloxy-functional moieties thereof;

each of a,b,c, and d is independently 0, 1, 2, or 3;

s is 0 or a positive integer; and

t is a positive integer;

provided that;

(a+b)=(c+d)=3;

(b+d+s)is greater than or equal to 2; and

the equivalents ratio of acryloxysilyl functionality to said additional functionality (ii) is selected from the group consisting of;

(A) an equivalents ratio of from 0.1;

0.9 to 0.8;

0.2; and

(B) 0.1;

0.9 to 1.0;

0.0, when the silicone is present with another material which is curable by curing conditions other than actinic radiation exposure curingly effective for the silicone by virtue of the acryloxy-functional moieties thereof.

3. A silicone according to claim 2, wherein each R is independently selected from C₁ -C₈ alkyl, and phenyl.

4. A silicone according to claim 2, wherein each R is methyl.

5. A silicone according to claim 2, wherein s is less than 20.

6. A silicone according to claim 2, wherein s is less than 8.

7. A photocurable composition comprising a silicone according to claim 2, and a photoinitiator.

8. A photocured product formed by exposure of the photocurable composition of claim 7 to radiation exposure conditions curingly effective therefor.

9. A cured silicone formed by subjecting the photocured silicone composition of claim 8 to additional curing conditions further curingly effective therefor to produce a fully cured silicone composition.

10. A silicone according to claim 1, comprising a photocurable silicone gel composition formed as a reaction product of:

(a) a first silane of the formula;

##STR38## 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;

##STR39## 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 polysiloxane 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.

11. A composition according to claim 10, wherein the reaction is carried out at a temperature of from about 0°

C. to about 100°

C.

12. A composition according to claim 10, wherein the reaction is carried out at room temperature.

13. A composition comprising a photocurable silicone gel composition according to claim 10, and an effective amount of a photoinitiator for curing of said photocurable silicone gel composition under radiation exposure curing conditions.

14. A composition according to claim 13, wherein the photoinitiator comprises a material selected from the group consisting of benzophenone, benzoin, acetophenone, benzil, and their substituted forms, and mixtures thereof.

15. A composition according to claim 13, wherein the photoinitiator comprises diethoxyacetophenone.

16. A composition according to claim 13, further comprising a filler.