Electron Spin Resonance Study of the Photolysis of Polystyrene and Poly(α-Methylstyrene)

Abstract

The photolysis of polystyrene and poly (α‐methylstyrene) was studied by ESR techniques using highly concentrated glassy solutions of the polymers near liquid‐nitrogen temperature. Every attempt was made to insure detection of the earliest free‐radical species. The use of poly (1‐vinylnaphthalene) and polystyrene‐2,3,4,5,6‐d 5 verified that the primary radical species is located on the polymer chain and not the ring. The ESR spectra obtained for both polystyrene and poly (α‐methylstyrene) are consistent with the structure H H – C – Ċ – C – H φ H . Interpretation of the observed spectra is made on the basis of the stereochemistry of the polymer chain.