High Char-Yield in AN-AM Copolymer by Acidic Hydrolysis of Homopolyacrylonitrile

Abstract

Acrylonitrile (AN)-acrylamide (AM) copolymers were prepared by nitric acidic hydrolysis of homopolyacrylonitrile. The acrylamino group increased as a function of hydrolysis time, while crystallinity decreased. Differential scanning calorimetry and a thermal gravimetric analysis indicated that the acylamino introduced by acidic hydrolysis effectively enhanced the cyclization reaction at low temperature due to the change of the cyclization reaction mechanism. Char-yield of AN-AM copolymers also gradually increased with increasing hydrolysis time. The maximum char-yield was 49.48% when hydrolized at 23°C in 65% nitric acid solution for 18 h, which was 30% higher than that of non-acidic hydrolysis of homopolyacrylonitrile. Simulation of the practical process also showed an increase of char yields, where the char yields were 55.43% and 62.60% for homopolyacrylonitrile and copolyacrylonitrile, respectively, with a hydrolysis time of 13 h.

Self-Assembly of Mn(II)-Amidoximated PAN Polymeric Beads Complex as Reusable Catalysts for Efficient and Stable Heterogeneous Electro-Fenton Oxidation

“…48-2119). 41,42 Compared with original PAN beads, the shift of the (100) crystal face was found with higher diffraction angles and obvious reduction in the intensity of characteristic peaks was observed for AOPAN beads, indicating that the surface amidoxime modification had significant effect on the crystal structure of polymeric beads. After being chelated with Mn(II) ion, the intensity of the diffraction peaks was lowered for both samples Mn−PAN and Mn−AOPAN.…”