Soluble Photosensitive Polyimide Precursor with Bisphenol A Framework: Synthesis and Characterization

A soluble photosensitive polyamide ester precursor (BAFPAE) was synthesized through copolymerization of 2,2-bis [4-(4-aminophenoxy)phenyl]hexafluoropropane (HFBAPP) with 4,4'-(4,4'-isopropylidenediphenoxy)bis(phthalic anhydride) (BPADA). Hydroxyethyl methacrylate (HEMA) was incorporated as a photosensitive functional group, and a transparent photosensitive polyimide film was obtained by thermal curing of the precursor film. The effects of reaction temperature and varying HEMA equivalents on the mechanical properties of the film were systematically investigated. The results indicated that the formation of polyacrylate-polyimide interpenetrating polymer networks (IPNs) was pivotal in preserving the mechanical integrity of the material. The optimized BAF-x-y exhibited a toughness of 12.69 MJ m³, a Young's modulus of 2.86 GPa, an elongation at break of 21.16%, and a tensile strength of 92.68 MPa.