US 5,204,408 A · Modified silicone vulcanization activator

Abstract

A modified organopolysiloxane comprising [R.sup.1.sub.2 SiO.sub.2/2 ] or [R.sup.1.sub.3 SiO.sub.1/2 ] units wherein R.sup.1 is a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms, at least two R.sup.1 substituents per molecule being replaced by specific isocyanurate or cyanurate groups is a vulcanization activator for assisting in vulcanization of fluorocarbon rubber or fluorocarbon/silicon rubber compositions with peroxide vulcanizing agents. It is prepared by reacting triallyl isocyanurate, triallyl cyanurate or a derivative thereof with dimethylchlorosilane or methyldichlorosilane in the presence of a platinum catalyst to form a chlorosilane containing diallylisocyanurate or diallylcyanurate groups, followed by hydrolysis. An alternative process is by reacting triallyl isocyanurate, triallyl cyanurate or a derivative thereof with a siloxane in the presence of a platinum catalyst.

Claims8

Dependent claims

A method of vulcanizing a rubber component with an organic peroxide in the presence of a vulcanization activator, wherein the rubber component contains a fluororubber, a mixture of a fluororubber and a silicone rubber, or a mixture of a fluororubber and a fluorosilicone rubber, the method comprising:

heating a mixture of the rubber component, the organic peroxide and the vulcanization activator in the presence of air to a temperature of 150.degree. C. to 200.degree. C. for about 10 to 30 minutes,
wherein the vulcanization activator is an organopolysiloxane comprising units selected from [R.sup.1.sub.2 SiO.sub.2/2 ] or [R.sup.1.sub.3 SiO.sub.1/2 ] wherein R.sup.1 is a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 21 carbon atoms, and wherein at least two R.sup.1 substituents per molecule are replaced by an isocyanurate or a cyanurate substituent selected from the group consisting of:
##STR24## wherein R.sup.3 is a --CH.sub.2 -- group, ##STR25## group, a --(CF.sub.2).sub.5 --OCH.sub.2 -- group, or a mixture thereof.

heating a mixture of the rubber component, the organic peroxide and the vulcanization activator in the presence of air to a temperature of 150.degree. C. to 200.degree. C. for about 10 to 30 minutes,
wherein the vulcanization activator is an organopolysiloxane having the formula:
##STR26## wherein R.sup.1 is a hydrogen atom, or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 21 carbon atoms,
R.sup.2 is a nitrogenous organic group represented by formula (1) or (4):
##STR27## wherein R.sup.3 is a --CH.sub.2 -- group, a ##STR28## group or a --(CF.sub.2).sub.5 --OCH.sub.2 --group, k is an integer of from 0 to 50,
m is an integer of 0 to 50,
n is equal to 1 or 2, and
wherein said Formula I organopolysiloxane contains at least two R.sup.2 substituents.

5 more elements

Dependencies are inferred from the claim text.

Modified silicone vulcanization activator

Life of this patent

Modified silicone vulcanization activator

Life of this patent

Abstract

Claims8