A Novel Characterization Method for Graft‐Polymer Structures Chemically Attached on Thermally Stable Polymer Films

Most polymer grafts in grafted polymer films obtained by radiation‐induced solid graft polymerization are not analyzed in detail due to difficulties in isolation of the grafts without structural decomposition. Herein, a novel structural and molecular weight characterization method is reported for polymer grafts that are chemically attached to thermally and chemically stable polymer substrates, based on a swelling‐induced graft detachment in hot water. Polymer grafts prepared by the radiation‐induced polymerization of alkyl acrylate into poly(ethylene‐ co ‐tetrafluoroethylene) (ETFE) followed by a sulfonation reaction are found to have a ternary copolymer structure whose monomer units contain –COOH or –SO 3 H groups, or both.