US 4,824,616 A · Method for the production of spherical silicone gel particles

Abstract

Spherical gel particles with elastomeric surfaces are made by dripping a liquid silicone gel composition containing alkenyl-containing organopolysiloxane, organohydrogenpolysiloxane, and a platinum catalyst into water or surfactant-containing water, curing and then contacting the surface of the silicone gel particles to organohydrogenpolysiloxane and curing to provide the elastomeric surface. The liquid silicone gel composition can also be extruded in fiber form into the water or surfactant-containing water with stirring to form the spherical particles which are cured and then the surface is contacted with organohydrogenpolysiloxane forming the silicone gel particles with elastomer surface. Alternatively, the liuqid silicone gel composition can be dripped or extruded in fiber form into a liquid having organohydrogenpolysiloxane to form the silicone gel particles with elastomer surface when the particles are cured. These spherical silicone gel particles are uniform and can be used to modify organic resins and be used for vibration absorption.

Claims8

Dependent claims

A method for the production of spherical silicone gel particles having a diameter of from 0.01 millimeters to 20 millimeters and having an elastomeric silicone layer on a silicone gel surface comprising

(a) forming cured spherical silicone gel particles by dispersing spherical particles of a liquid silicone gel composition in water and curing, where the liquid silicone gel composition comprises
(A) organopolysiloxane having at least two lower alkenyl groups in each molecule,
(B) organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms in each molecule, in a quantity such that the molar ratio between the total quantity of silicon-bonded hydrogen atoms in component (B) and the total quantity of all lower alkenyl groups in component (A) is from 0.1:1 to 1:1, and
(C) a platinum catalyst at 0.1 to 1,000 parts by weight of platinum metal for each one million parts by weight of the total quantity of components (A) plus (B), and
(b) forming the elastomeric layer on the surface of the spherical silicone gel particle by contacting the particles with organohydrogenpolysiloxane and curing to form the elastomer.

2 more elements

Dependencies are inferred from the claim text.

Method for the production of spherical silicone gel particles

Life of this patent

Method for the production of spherical silicone gel particles

Life of this patent

Abstract

Claims8