1. College of Chemical and Biological Engineering, State Key Laboratory of Chemical Engineering, Zhejiang University, Hangzhou 310058, China;
2. Institute of Zhejiang University - Quzhou, Quzhou 324000, China
Abstract:The copolymerization reaction of 2,5-dihydroxytoluene, hydroquinone and 4,4’-difluorobenzophe was studied. The results showed that the molecular weight distribution of the PEEK-CH3 initially decreased and then increased with an elevation in solid content, reaction temperature, and the ratio of potassium carbonate to phenolic monomers in alkali metal carbonate. The optimal reaction conditions were identified as follows: a solid content of 25%, condensation temperature of 200 ℃, molar ratio of alkali metal carbonate to phenolic monomer was 1.05:1, molar ratio of sodium carbonate to potassium carbonate in alkali metal carbonate was 19:1, and reaction time was 3.5 h. In the PEEK-CH3 bromination reaction, the proportion of the crucial dibromide substitution product (PEEK-CHBr2) was critical. With a liquid bromine dosage 20 times that of the —CH3 molar equivalent, a reaction temperature of 160 ℃, UV light conditions at 365 nm, and reaction time 2 h, the PEEK-CHBr2 proportion reached 95.8%. Finally, through the oxidation of PEEK-CHBr2 with sodium hypochlorite, carboxyl-functionalized polyether ether ketone (PEEK-COOH) was successfully synthesized with an average molecular weight of 4.6×104 and a characteristic viscosity of 1.5 dL/g. The water contact angle decreased from 133.9° of unmodified PEEK to 29.9°.
. Preparation of Carboxylated Polyether Ether Ketone via Copolymerization of Methoxyphenol Monomer-Bromination-Carboxylation[J]. Chemical Reaction Engineering and Technology, 2024, 40(2): 150-159.