- 作者: 唐政猷 ; 施正雄
- 作者服務機構: 台灣師範大學化學系
- 中文摘要: Various crown ethers were used as phase-transfer catalysts for free radical polymerizations of some water-insoluble vinyl monomers such as acrylonitrile, methylmethacrylate and styrene with persulfate as initiator. The catalytic abilities of these crown ethers for free radical polymerization of acrylonitrile with S/sub 2/ O/sub 8//sup 2-/ ion as an initiator were in the order: 18- crown-6>15-crown-4>12-crown-4>benzo-15-crown-5>dibenzo-18- crown-6. Among various persulfates such as Na/sub 2/S/ sub 2/ O/sub 8/, K/sub 2/S/sub 2/O/sub 8/ and (NH/sub 4/)/sub 2/ S/sub 2/O/sub 8/, ammonium persulfate was the optimum initiator for the polymerization of acrylonitrile catalyzed by 18-crown-6 or 15-crown-5. Among the organic solvents used, chloroform seems to be the best solvent for the catalytic polymerization of acrylonitrile. An apparent activation energy of 72.9kJ/mol was observed for the polymerization of acrylonitrile. The catalytic reaction rates of free radical polymerization for these hydrophobic vinyl monomers were in the order: acrylonitrile>methylmethacrylate>styrene>isoprene. Effects of concentrations of crown ether, initiator, and nitrogen on the polymerization of these vinyl monomers were investigated.
- 英文摘要: --
- 中文關鍵字: Crown Ether; Phase Transfer Catalyst; Free Radical Polymerization; Hydrophobic Vinyl Monomer; Initiator
- 英文關鍵字: 冠醚;相轉移觸媒;自由基聚合;疏水性乙烯單分子;啟始劑