Polyaddition Reaction

Abstract

Polyurethanes are typical polymers synthesized by polyaddition reaction. This article reviews reactions used in polyurethane synthesis, reaction mechanism of isocyanate with active hydrogen groups by use of quantum computer chemistry, the role of hard segment length, and design criteria of high performance polyurethanes. The reactions were speculated to proceed via formation of hydrogen bonding and six membered ring 1: 2 complexed of isocyanate with alcohol, water, and amine. The calculated activation energy for reaction of phenyl isocyanate with ethanol or methylamine was 12.4 and 4.12 kcal mol^-1, respectively. The design criteria of polyurethane are described from a point of view of chemical and physical factors.