Preparation and thermal properties of poly[acrylonitrile-co-(β-methylhydrogen itaconate)] used as carbon fiber precursor

摘要: In order to replace terpolymer with bipolymer, a bifunctional comonomer β-methylhydrogen itaconate (MHI) containing carboxyl group and ester was synthesized prepare poly[acrylonitrile-co-(β-methylhydrogen itaconate)] [P(AN-co-MHI)] bipolymers used as carbon fiber precursor for improving the stabilization spinnability at same time. The P(AN-co-MHI) different monomer feed ratios were characterized by elemental analysis, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC). results show that both polymerization conversion molecular mass of reduce increasing MHI amounts in due larger volume than acrylonitrile (AN). reactivity calculated Fineman–Ross Kelen–Tudos methods, good agreement possesses higher AN. Two parameters \( E_{\text{s}} = A_{{1,629\,{\text{cm}}^{ - 1} }} /A_{{2,244\,{\text{cm}}^{ \) SI (I_{0} I_{\text{S}} )/I_{0} defined evaluate extent stabilization, activation energy (Ea) cyclization Kissinger method Ozawa method. FTIR, XRD, DSC exhibit significantly improved characteristics PAN homopolymer, such lower initiation temperature, smaller Ea cyclization, which is attributed ionic it beneficial preparing high-performance fiber.