Degradation and kinetic modeling of polyvinyl alcohol in aqueous solutions by a H2O2/Mn(II) system

作者:Su, Yangfan; Li, Mengjuan*; Gao, Qiang; Li, Xiaoqiang; Ju, Anqi; Lu, Yang; Ge, Mingqiao*
来源:Fibers and Polymers, 2017, 18(12): 2269-2277.
DOI:10.1007/s12221-017-1092-y

摘要

This paper is about the degradation of polyvinyl alcohol (PVA) in aqueous solutions using a H2O2/Mn(II) system. Fourier transform infrared spectroscopy (FTIR) and gel permeation chromatography (GPC) were applied to analyze the degradation products of PVA, and the results revealed that the backbone chain of PVA could be effectively broken and oxidized. Several unsaturated degradation products, including carboxylic acids, ketones, aldehydes, olefins, and alkynes were also detected and identified by gas chromatography-mass spectrometry (GC-MS), which indicated that higher treatment temperatures would considerably promote the generation of lower molecular weight degradation products. According to the work presented in this paper, the degradation efficiency of PVA increased from 55 % at 60 oC to 99 % at 90 oC after treatment when the initial PVA concentration was 5 %, at pH=3 with a H2O2 and Mn(II) dose of 100 ml/l and 0.6 mol/l, respectively. In addition, kinetic modeling indicated that the experimental results were best fitted by the Page-modified model with an activation energy of 48.78 kJ/mol.