화학공학소재연구정보센터
Journal of Polymer Science Part A: Polymer Chemistry, Vol.32, No.14, 2699-2708, 1994
Multifinctional Coupling Agents for Living Cationic Polymerization .4. Synthesis of End-Functionalized Multiarmed Poly(Vinyl Ethers) with Multifunctional Silyl Enol Ethers
Telechelic (8) and end-functionalized four-arm star polymers (9) were synthesized through the coupling reactions of end-functionalized living poly(isobutyl vinyl ether) (5; DPBAR(n) approximately 10) with the bi- and tetrafunctional silyl enol ethers, H4-nC - [CH2OC6H4C(OSiMe3) = CH2]n (3 : n = 2; 4 : n = 4). The precursor polymers 5 were prepared by living cationic polymerization with functionalized initiators, CH3CH(Cl)OCH2CH2X (6), in conjunction with zinc chloride in methylene chloride at -15-degrees-C. The initiators 6 were obtained by the addition of hydrogen chloride gas to vinyl ethers bearing pendant functional groups X, including acetoxy [ - OC(O)CH3], styryl (- OCH2C6H4-p-CH = CH2), and methacryloyl [- OC(O)C(CH3) = CH2]. The coupling reactions with 3 and 4 in methylene chloride at -15-degrees-C for 24 h afforded the end-functionalized multiarmed polymers (8 and 9) in high yield (> 91%), where those with styryl or methacryloyl groups are new multifunctional macromonomers.