Chapter 1 The Beginner's Course: General Description of Transition Metal Catalysts and Catalytic Polymerization Reactions

Abstract

Publisher Summary This introductory chapter describes a large family of transition metal catalysts used for the polymerization of various alkenes. Two sets of definitions related to alkene polymerization reactions are used interchangeably in academia and in industry: (1) The historic name for alkenes, “olefins,” is universally used in industry, whereas researchers in academia usually prefer the chemically correct term, “alkenes;” and (2) Alkene polymers are nearly always called “polyolefins.” Terms ‘‘polymers'’ or ‘‘copolymers'’ are used for the description of these materials in academia (e.g., propylene polymers, ethylene/1-alkene copolymers), whereas the same materials are called ‘‘resins'’ in industry—polypropylene resins, linear low-density polyethylenes (LLDPE) resins, etc. The development of numerous new catalysts for alkene polymerization in the last 20 years called for separation of all transition metal-based polymerization catalysts into several groups. The following general terminology is commonly adopted. The first group, which includes mostly titanium and vanadium-based catalysts, has retained the name ‘‘Ziegler–Natta catalysts.’’ The members of the second catalyst group are commonly called ‘‘metallocene polymerization catalysts.’’ The third group includes polymerization catalysts based on hydrocarbon-soluble non-metallocene transition metal complexes. The fourth group constitutes chromium-based catalysts.