Health & Environmental Research Online (HERO)


Print Feedback Export to File
6616594 
Journal Article 
Living cationic polymerization of beta-pinene with 1-phenylethyl chloride/TiCl4/Ti(OiPr)(4) 
Lu, J; Liang, H; Zhang, RF; , 
2000 
1 
Gaodeng Xuexiao Huaxue Xuebao / Chemical Journal of Chinese Universities
ISSN: 0251-0790 
HIGHER EDUCATION PRESS 
BEIJING 
1932-1935 
WOS:000167004800038 
The cationic polymerization of beta -pinene was carried out with l-phenylethyl chloride as an initiator and the mixture of TiCl4 and tetraisopropoxytitanium [Ti(OiPr)(4)] as a Lewis acid activator in CH2Cl2 at -40 degreesC. The polymerization with strong Lewis acid TiCl4 alone completed instantaneously and gave the polymers with broad molecular weight distributions. The addition of weak Lewis acid Ti(OiPr)(4), which alone had no catalytic activity for beta -pinene, retarded the polymerization by TiCl4 and led to polymers with narrower molecular weight distributions. When [Ti(OiPr)(4)](0)/[TiCl4](0)=1/3, the number-average molecular weight of the polymers increased in direct proportion to monomer conversion, and the molecular weight distribution of the polymers was narrow. The living nature of the polymerization was further demonstrated by monomer-addition experiments. H-1 NMR analysis of the polymers obtained at [Ti(OiPr)(4)](0)/[TiCl4](0)=1/3 showed that l-phenylethyl chloride served as an initiator and generated poly (beta -pinene) chains with the CH3CH(C6H5) head group and a tert-Cl tail group.