Structure and kinetic rigidity of polymers as related to chain relaxations

Abstract

Kinetic rigidity of several polymers such as 2,6-bis(3-aminophenoxy)benzonitrile/4,4′oxydiphthalic anhydride (β-CN)APB/ODPA, poly[(2,2-dimethyl-1,3-dioxolan-4-yl)methyl acrylate)] (PACGA), and diglycidyl ether of bisphenol A (DEGEBA) was studied. Rigidity parameter D, Vogel’s temperature T0, and the activation energy Uα ( Tg) for the glass transition were evaluated through Vogel’s model along with relaxation data using “nonlinear” regression of Arrhenius function. The existence of certain functional groups within the structure, such as the aromatic rings, gives high level of kinetic rigidity to the structure as is the case of (β-CN)APB/ODPA and DEGEBA, while the aliphatic groups confer flexibility, as in PACGA.