22.1 Introduction

  • Polymerization is a reaction in which chain-like macromolecules (polymers) are formed by combining small molecules (monomers).

  • Natural polymers: cellulose, proteins, etc.

  • Many modern commercial products are derived from polymers.

  • Commercial polymers have molecular weights greater than 5,000.

  • A homopolymer is a macromolecule derived from a single monomer, whereas a copolymer contains structural units of two or more different precursors.

  • Resin: In polymer technology the term resin usually means a powdered or granular synthetic polymer suitable for use, possibly with the addition of other nonpolymeric ingredients.

  • The huge polymer market directly results from extensive work in synthetic organic compounds and catalysts. Ziegler’s discovery of a coordination catalyst in the titanium family paved the road for synthesizing many stereoregular polymers with improved properties. Even greater control of the polymerization is obtained using a new class of catalysts—the metallocenes.