General Electric Company

David Francis Townsend

Robert Edgar Colborn

Roy M Griswold

Shaow B Lin

Vern Lowry

Matthew Hal Littlejohn

Shripathy Vilasagar

Ronald A Greenberg

Ke Feng

Dane M Ferraris

Ference Horkay

An emulsion polymerization process for the preparation of polybutadiene grafted with styrene and acrylonitrile monomers in a reaction system is provided. The resultant product has a low end content of unreacted residual monomers, low yellowness index, and improved impact strength. The diene rubber is prepared via a process wherein a chain transfer agent is added on a continuous basis to give a rubber substrate having a low crosslink density. In one embodiment of the invention, the process includes charging the reaction system with a pre-selected diene emulsion with a low crosslink density, adding a first portion of at least one of a styrene monomer and acrylonitrile monomer to the diene emulsion, adding to the reaction system, over a predetermined time, an initiator and a second portion of acrylonitrile and styrene monomer, and polymerizing the catalyzed reaction mixture of diene substrate, styrene and acrylonitrile to form ABS graft polymers. In another embodiment, a third monomer is added after the conversion rate of the monomers is greater than 98%.

Enhanced polymerization process

A pressure sensitive adhesive composition includes an alkenyl-terminated polydiorganosiloxane, a silanol-terminated polydiorganosiloxane, a resinous copolymer, an organohydrogenpolysiloxane with terminal Si&mdash;H groups, a hydrosilation catalyst, and an organic cross-linking agent. The composition provides excellent high temperature adhesion properties and enables coatable formulations with low solvent content.

Dual cure, low-solvent silicone pressure sensitive adhesives

Growing community of inventors

Loganville, GA, United States of America

David Francis Townsend