This technology is available from Temarex Corporation.

BICOMPONENT NETWORKS OF POLYISOBUTYLENE AND SILOXANE

Title: MULTI-COMPONENT POLYMERIC NETWORKS CONTAINING POLYISOBUTYLENE

Inventor(s): J. Kennedy, M. Sherman

Disclosure 308 U.S. Patent not yet issued

This invention relates to synthesis of bicomponent networks (BCNs) containing polyisobutylenes (PIB) and polysiloxanes.

These bicomponent networks (BCNs) are synthesized by linking multifunctional PIB with bifunctional linear polysiloxanes by hydrosilation. Similarly, multiblock copolymers are synthesized by endlinking difunctional allyl-terminated PIB with difunctional SiH-terminated linear polysiloxanes by hydrosilation.

The bicomponent networks of the present invention should be distinguished from more traditional interpenetrating polymer networks (IPNs). A BCN is defined as a single elastomeric network comprising two chemically different covalently bonded sequences; whereas, an IPN consists of two or more unlinked independent networks. The distinction to be made is significant in that the polymers in the IPNs are not linked chemically, but rather are two separate tangled networks. Most two-component systems studied to date concern IPNs, with very few studies having been performed using BCNs.

BCNs containing PIBs and polysiloxanes may be of great commercial interest to the extent that PIB is known for low cost, superior mechanical properties, extremely low gas permeability and excellent environmental, hydrolytic and high temperature resistance while, in contrast, polysiloxanes, such as polydimethylsiloxanes (PDMS) are relatively expensive, have poor mechanical properties, but excel in regard to high gas permeability, low surface energy and biocompatibility.

BCNs of the present invention are swellable elastomers and are believed to have significant ramifications in the rubber industry by taking advantage of the combined PIB\polysiloxane properties to control gas permeability, water repellency, environmental stability and biocompatibility. Thus this invention provides a new material for possible applications in biotechnology, insulation, separation membranes, fabric coating to confer water repellency, emulsifying or compatibilizing agents, gaskets, adhesives, sealants, o-rings, grommets, electrical connectors and the like.

From review of experimental data, it was surprisingly noted that the BCN films (about 0.8 mm thick) were optically clear over the entire composition range examined (small newsprint clearly legible upon overlay), suggesting the presence of very efficient phase mixing.