私密直播全婐app免费大渔直播,国产av成人无码免费视频,男女同房做爰全过程高潮,国产精品自产拍在线观看

相關鏈接
聯系方式
  • 通信地址:成都市武侯區望江路29號,四川大學化學學院
  • 郵編:610064
  • 電話:028-85410755
  • 傳真:
  • Email:wu_china_chengdu@126.com
當前位置:> 首頁 > 論文著作 > 正文
Copolymerization of poly (vinyl alcohol)-graft-poly (1, 4-dioxan-2-one) with designed molecular structure by a solid-state polymerization method
作者:SC Chen, XL Wang, KK Yang, G Wu, YZ Wang
關鍵字:biodegradable, solid-state polymerization, graft copolymer, poly(vinyl alcohol), poly(1,4-dioxan-2-one)
論文來源:期刊
具體來源:Journal of Polymer Science Part A: Polymer Chemistry
發表時間:2006年
Poly(vinyl alcohol)-graft-poly(1,4-dioxan-2-one) (PVA-g-PPDO) with designed molecular structure was synthesized by a solid-state polymerization. The solid-state copolymerization was preceded by a graft copolymerization of PDO initiated with PVA as a multifunctional initiator, and Sn(Oct)(2) as a coininitiator/catalyst in a homogeneous molten state. The polymerization temperature was then decreased and the copolymerization was carried out in a solid state. The products prepared by solidstate polymerization were characterized by H-1 NMR and DSC, and were compared with those synthesized in the homogeneous molten state. The degree of polymerization (D-p), degree of substitution (D-s), yield and the average molecular weight of the graft copolymer with different molecular structure were calculated from the H-1 NMR spectra. The results show that the crystallization process during the solid-state polymerization may suppress the undesirable inter- or intramolecular side reactions, then resulting in a controlled molecular structure of PVA-g-PPDO. The results of DSC measurement show that the molecular structures determine the thermal behavior of the PVA-g-PPDO.
主站蜘蛛池模板: 迁西县| 思南县| 舒兰市| 镇江市| 青龙| 白玉县| 方正县| 都江堰市| 泰来县| 双鸭山市| 繁峙县| 平度市| 南岸区| 丽江市| 甘孜县| 商洛市| 尖扎县| 同仁县| 荆门市| 武陟县| 蒙阴县| 突泉县| 阿合奇县| 务川| 永寿县| 阿克陶县| 长垣县| 永修县| 青田县| 廊坊市| 通海县| 永州市| 东港市| 乐至县| 襄垣县| 大悟县| 米脂县| 东海县| 昭平县| 奎屯市| 灵宝市|