A new process based on mixed-solvent precipitation polymerization to synthesize high molecular weight polyacrylonitrile initiated by ammonium persulphate
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- 作者：Yaqi Zhao ; Jingjing Liang ; Mixue Peng ; Lin Xu ; Zhenzhen Shao…
- 关键词：Acrylonitrile ; Itaconic acid ; Mixed ; solvent precipitation polymerization ; Ammonium persulphate
- 刊名：Fibers and Polymers
- 出版年：2016
- 出版时间：December 2016
- 年：2016
- 卷：17
- 期：12
- 页码：2162-2166
- 全文大小：
- 刊物类别：Chemistry and Materials Science
- 刊物主题：Polymer Sciences;
- 出版者：The Korean Fiber Society
- ISSN：1875-0052
- 卷排序：17
文摘
To obtain high performance polyacrylonitrile (PAN) polymers used to manufacture carbon fibers, high molecular weight acrylonitrile and itaconic acid (AN/IA) copolymers were successfully synthesized by mixed-solvent precipitation polymerization in dimethyl sulfoxide/water (DMSO/H2O) using the water-soluble initiator ammonium persulphate (APS) for the first time. Effects of the DMSO/H2O ratios and the AN/IA monomer ratios on the polymerization conversion and the molecular weight were discussed. Chemical structures and compositions of the PAN polymers were characterized by Fourier transform infrared (FTIR) spectroscopy and elemental analysis (EA). It is shown that the molecular the molecular weight of the produced polymers increased when the DMSO content decreased and reached a maximum value at 40 wt%. With furture decrease in the DMSO content, the molecular weight gradually decreased. The highest polymerization conversion was obtained at a DMSO/H2O ratio of 60/40 (wt/wt). The polymerization conversion exhibited slow growth until an increase in the IA content less than 4 wt%, and then reduced at an IA content of 10 wt%. The stretching vibration bands of the nitrile (C≡N) and carbonyl (C=O) groups dominated the FTIR spectra of the PAN polymers, indicating the presence of IA in the polymers. In addition, the oxygen contents determined in the polymers by EA were consistent with the increasing amount of added IA. Therefore, it should be supported that the copolymerization of AN and IA occurred via a mixed-solvent polymerization process.