Radiation degradation of α‐substituted acrylate polymers and copolymers

Radiation degradation is observed in poly(methyl α‐chloroacrylate), poly(methyl α‐cyanoacrylate), and poly(α‐chloroacrylonitrile) homopolymers and their respective MMA copolymers when γ‐irradiated in vacuo. Polymer degradation susceptibilities are quantified in terms of G(scission radicals) and G(scission) − G(crosslinks), measured by EPR and membrane osmometry, respectively, values by these two methods are compared. Higher G(rads) values ranging from 2 to 6 and [G(s) − G(x)] values ranging from 2 to 11 are obtained for the substituted polymers and copolymers relative to the values for PMMA (1.6; 1.9), a standard e‐beam positive resist, which suggests that these modified polymers are more sensitive e‐beam resists than PMMA.