SCIENCE AND SERENDIPITY IN POLYOLEFIN ELASTOMER DEVELOPMENT

Abstract

Abstract Polyolefin elastomers based on ethylene, propylene, and isobutylene plus other monomers are now widely used in many diverse applications. Major research and development efforts have led to thermoplastic polyolefin soft automobile bumpers, modifiers for lubricating oils, and fast extrusion grades of ethylene–propylene–diene terpolymers. These and other successful commercial innovations depend on the tools of the basic science of structure–property relationships, proper needs assessments, sound engineering, and good management. These tools have been largely provided by my colleagues at ExxonMobil Chemical, customers, and universities and I thank them profoundly. Several historical commercial developments are discussed, including thermoplastic polyolefin elastomers based on ethylene–propylene copolymer–isotactic–polypropylene blends, shear stable viscosity modifiers based on ethylene–propylene copolymers, bimodal molecular weight and compositional distribution EPDM to control rheological characteristics, and diene structure and interchain distribution. In addition, the ongoing research on nanocomposites for tire innerliners based on isobutylene polymers and clay is reviewed. The roles of polymer science, serendipity, and lost opportunity costs on innovation are also discussed.