Dual temperature curable silicone compositions, methods of manufacture, and articles prepared therefrom

Abstract

Dual temperature curable silicone compositions, articles made from such compositions, and methods for the manufacture and use thereof. In particular, a dual temperature curable silicone composition is manufactured from a composition comprising a vinyl silicone; a silicone hydride-containing crosslinker, a platinum-containing catalyst; and a peroxide catalyst.

1 . A dual temperature curable silicone composition, comprising:
 100 parts by weight of a vinyl silicone;   0.05-10 parts by weight of a silicone hydride-containing crosslinker;   0.5-5 parts by weight of a platinum-containing catalyst; and   0.2-5 parts by weight of a peroxide catalyst.   
     
     
         2 . The composition of  claim 1 , wherein the vinyl silicone is of Formula (I):
   R B [Si(R 1 R 2 )—O]—[(Si(R 3 R 4 )—O)] n —[Si(R 5 R 6 )—O)] m —Si(R 1 R 2 )—R A   (Formula I)
   wherein
 n has an average value of 1 to 200; 
 m is 0 or has an average value of 1 to 20,000; 
 R A , R B , R 1 , R 2 , R 3 , R 4 , R 5  and R 6  are each independently a C 1 -C 6  alkyl group; and 
   at least one of R A , R B , R 3  and R 4  has the formula —CH═CR F R G , where R F  and R G  are each independently hydrogen or a C 1 -C 6  alkyl group.   
     
     
         3 . The composition of  claim 2 , wherein at least one of R A , R B , R 3  and R 4  is —CH═CH 2 . 
     
     
         4 . The composition of  claim 2 , wherein at least one of R A  or R B  is —CH═CH 2  and R 1  and R 2  are both methyl groups. 
     
     
         5 . The composition  claim 1 , wherein
 the vinyl silicone comprises a polydiorganosiloxane functionalized with a terminal —Si(Me) 2 -CH═CH 2  group; and   the silicone hydride-containing crosslinker is of Formula (II):
   R D —Si(R 7 R 8 )O—[Si(R 9 R 10 )—O)] x —[Si(R 11 R 12 )—O)] y —Si(R 13 R 14 )—R E   (Formula II)
 
   
       wherein
 at least one of R D , R E , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13  and R 14  is hydrogen, and the others of R D , R E , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13  and R 14  are each independently hydrogen, or C 1 -C 6  alkyl; 
 x has an average value of 1 to 300; and 
 y is 0 or has an average value of 1 to 300. 
 
     
     
         6 . (canceled) 
     
     
         7 . The composition of  claim 5 , wherein both of R D  and R E  are hydrogen and R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13 , and R 14  are methyl. 
     
     
         8 . The composition of  claim 5 , wherein y is 0; both of R D  and R E  are methyl; R 9  is hydrogen and R 7 , R 8 , R 10 , R 13 , and R 14  are methyl. 
     
     
         9 . The composition of  claim 5 , wherein both of R D  and R E  are methyl; R 9  is hydrogen and R 7 , R 8 , R 10 , R 11 , R 12 , R 13  and R 14  are methyl. 
     
     
         10 . (canceled) 
     
     
         11 . The composition of  claim 1 , wherein
 the platinum-containing catalyst comprises a Pt(0) complex, a Pt(II) complex, a Pt(IV) complex, or a combination comprising at least one of the foregoing; and   the peroxide catalyst comprises an organic peroxide; an aliphatic peroxide; an aromatic peroxide; an organic hydroperoxide; or a combination comprising at least one of the foregoing.   
     
     
         12 . (canceled) 
     
     
         13 . The composition of  claim 11 , wherein the peroxide catalyst comprises benzoyl peroxide; di-t butyl peroxide; 2,4-dichlorobenzoyl peroxide; or 2,5-bis(t-butylperoxy)-2,5-dimethylhexan. 
     
     
         14 . The composition of  claim 1 , wherein the platinum-containing catalyst and peroxide catalyst are present in a weight percent ratio of 0.001:1 to 1:1. 
     
     
         15 . (canceled) 
     
     
         16 . (canceled) 
     
     
         17 . A method of fully curing a dual temperature curable silicone composition, comprising:
 providing a silicone composition of  claim 1 ;   exposing the silicone composition to a first temperature to activate the platinum catalyst but not the peroxide catalyst, to form a semi-cured composition; and   heating the semi-cured composition to a second temperature sufficient to activate the peroxide catalyst, to form a fully cured composition.   
     
     
         18 . The method of  claim 17 , wherein the first temperature is below 100° C., and the second temperature is 70° C. to 200° C., provided that the second temperature is higher than the first temperature. 
     
     
         19 . The method of  claim 17 , further comprising forming the semi-cured or fully cured silicone composition into a shape. 
     
     
         20 . (canceled) 
     
     
         21 . A method of semi-curing a dual temperature curable silicone composition, comprising:
 providing a dual temperature curable silicone composition comprising a vinyl silicone; a silicone hydride-containing crosslinker; a platinum-containing catalyst; and a peroxide catalyst;   exposing the silicone composition to a first temperature to activate the platinum catalyst but not the peroxide catalyst to form a semi-cured composition.   
     
     
         22 . The method of  claim 21 , wherein the first temperature is below 100° C. 
     
     
         23 . The method of  claim 21 , further comprising forming the curable composition or the semi-cured composition into a desired shape. 
     
     
         24 . (canceled) 
     
     
         25 . (canceled) 
     
     
         26 . A method of forming a semi-cured article comprising:
 providing the silicone composition of  claim 1 ;   exposing the uncured composition to a first temperature to activate the platinum catalyst but not the peroxide catalyst, to provide a semi-cured composition; and   shaping the semi-cured composition to provide a shaped, semi-cured article.   
     
     
         27 . A method of forming a semi-cured article comprising:
 shaping the silicone composition of  claim 1 ; and   exposing the shaped uncured composition to a first temperature to activate the platinum catalyst but not the peroxide catalyst, to provide a shaped, semi-cured article.   
     
     
         28 . A method of forming an article comprising:
 providing the silicone composition of  claim 1 ;   exposing the uncured composition to a first temperature to activate the platinum catalyst but not the peroxide catalyst, to provide a semi-cured composition;   shaping the semi-cured composition to provide a semi-cured article; and   heating the semi-cured composition to a second temperature sufficient to activate the peroxide catalyst, to form a fully cured article.   
     
     
         29 . A method of forming an article comprising:
 shaping the silicone composition of  claim 1  to form an uncured article;   exposing the uncured article to a first temperature to activate the platinum catalyst but not the peroxide catalyst, to provide a semi-cured article; and   heating the semi-cured article to a second temperature sufficient to activate the peroxide catalyst, to form a fully cured article.   
     
     
         30 . The method of  claim 26 , wherein the first temperature is below 100° C., and the second temperature is 70° C. to 200° C., provided that the second temperature is higher than the first temperature. 
     
     
         31 . The method of  claim 26 , wherein the shaping comprises casting or calendering to form a layer. 
     
     
         32 . The method of  claim 26 , further comprising forming the layer on a substrate, wherein the substrate has been treated with a a vinyl tris(alkoxyalkoxy)silane primer. 
     
     
         33 . The method of  claim 32 , wherein the vinyl tris(alkoxyalkoxy)silane is the vinyl tris(alkoxyalkoxy)silane is vinyl tris[(C 1 -C 6  alkoxy C 1 -C 6  alkoxy)]silane is present in an amount of 2-20 parts by weight. 
     
     
         34 . (canceled) 
     
     
         35 . The method of  claim 26 , wherein the second temperature is achieved by laminating the article.