Curable silicone composition

• US 4,654,408 A
• Filed: 03/14/1986
• Issued: 03/31/1987
• Est. Priority Date: 03/14/1985
• Status: Expired due to Term

• Current Assignee: Shin-Etsu Chemical Company Limited
• Original Assignee: Shin-Etsu Chemical Company Limited
• Inventors: Okinoshima, Hiroshige
• Primary Examiner(s): Marquis, Melvyn I.
• Application Number:
  US06/839,562
• Time in Patent Office: 382 Days
• Field of Search: 528/32, 528/15, 528/33, 556/430, 524/861, 524/862
• US Class Current: 528/15
• 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

Abstract

A curable silicone composition comprising (A) an organosilicon compound having at least two radicals of the formula: ViSi(R¹)₂ Si(R¹)₂ --Z-- wherein R¹ is a lower alkyl radical and Z is a bivalent radical of --O-- or --CH₂)_n in which n is an integer of 1 to 3, (B) a platinum catalyst, and optionally (C) an organosilicon compound having silicon bonded vinyl groups. The composition is cured through a new crosslinking mechanism without any byproducts, and has high stability at normal temperatures and good curability.

Claims

1. A curable silicone composition comprising:

(A) an organosilicon compound represented by the formula (I);

##STR8## wherein Vi represents vinyl radical, R¹, which may be the same or different, is a lower alkyl radical, R² is a substituted or unsubstituted univalent hydrocarbon radical, Z is a bivalent radical represented by --O-- or --CH₂ --_n wherein n is an integer of from 1 to 3, and a and b are numbers such that 0<

a≦

4, 0≦

b<

4 and 0<

a+b≦

4, and having at least two radicals of the formula;

ViSi(R¹) ₂ Si(R¹) ₂ --z-- in it molecule, and

(B) a platinum catalyst.

2. A composition according to claim 1, wherein said organosilicon compound of component (A) is:

ViMe₂ SiMe₂ SiO(SiMe₂ O)_n SiMe₂ SiMe₂ Vi,

ViMe₂ SiMe₂ SiCH₂ CH₂ SiMe₂ O(SiMe₂ O)_n -SiMe₂ CH₂ CH₂ SiMe₂ Vi, or

[(ViMe₂ SiMe₂ SiCH₂ CH₂ SiMe₂ O)₂ RSi]₂ O

wherein n is an integer of not less than 0, and R represents a lower alkyl group.

3. A composition according to claim 1 or 2, wherein the content of said platinum catalyst of component (B) is from 1 to 100 ppm, as platinum, in the whole composition.

4. A composition according to claim 1, which further comprises:

(C) an organosilicon compound represented by the formula (II);

##STR9## wherein Vi represents vinyl radical, R³ is a substituted or unsubstituted univalent hydrocarbon radical, and c and d are numbers such that 0<

c≦

4, 0≦

d<

4 and 0<

c+d≦

4, and, where c+d has a value of less than 4, having at least two silicon atoms to each of which at least two vinyl radicals are bonded, or, where c+d has a value of 4, having at least three vinyl radicals in its molecule.

5. A composition according to claim 4, wherein said organosilicon compound of component (C) is:

##STR10## wherein n is an integer of not less than 0.

6. A composition according to claim 4, wherein the amount of said organosilicon compound of component (C) is not more than 10,000 parts by weight per 100 parts by weight of said organosilicon compound of component (A).

7. A composition according to claim 6, wherein the amount of said organosilicon compound of component (C) is from 100 to 1,000 parts by weight per 100 parts by weight of said organosilicon compound of component (A).

8. A composition according to claim 4, 5, 6 or 7, wherein the content of said platinum catalyst of component (B) is from 1 to 100 ppm, as platinum, in the whole composition.

9. A composition according to claim 1 or 4 which further comprises at least one selected from the group consisting of inorganic fillers, pigments, dyes, antioxidants and reaction inhibitors.