Synthesis and Properties of Co‐Poly(Aryl Ether Ketone) With Bulky Side Groups and Enhanced Heat Deflection Temperature

ABSTRACT A series of copolymerized Poly(aryl ether ketone) (co‐PAEK) materials were synthesized through the copolymerization of hydroquinone (HQ), phenolphthalein anilide (PPA), and 4,4′‐difluoro diphenylmethanone (DFBP). When the feed ratio of HQ to PPA varied from 0:10 to 5:5, the resulting copolymers were amorphous and showed good solubility in organic solvents. While, when the HQ to PPA ratio reached 7:3 or higher, the copolymers exhibited a semi‐crystalline structure. By incorporating bulky and non‐coplanar side groups into the backbone of polyetheretherketone (PEEK), the glass transition temperature ( T g ) significantly increased from 143°C to 246°C, and the heat deflection temperature (HDT) rose from 151°C to 237°C. The creep tests conducted at 150°C demonstrated that the co‐PAEKs possess superior dimensional stability compared to PEEK. These enhanced properties suggest that the co‐PAEKs have potential applications in areas such as polymer bearings and gears.