Both terminated functional isotactic polypropylene (iPP) and blockcopolymers containing iPP segment are desirable for commercial applications. This paper provides a convenient, highly-efficient method to prepare hy...
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Both terminated functional isotactic polypropylene (iPP) and blockcopolymers containing iPP segment are desirable for commercial applications. This paper provides a convenient, highly-efficient method to prepare hydroxyl-terminated isotactic polypropylene (iPP-t-OH) and functional di-blockcopolymer containing the iPP segment through a combination of coordination polymerization and couplingreaction. The coordination polymerization was catalyzed by TiCI4/MgCI2/AIEt3 catalyst system using ZnEt2 as chain transfer agent. Further, the Zn-terminated iPP was oxidized and subsequently hydrolyzed to provide iPP-t-OH. Soxhlet extraction and 13C NMR were used to calculate the isotacticity of iPP-t-OH. The degree of polymerization and the number of hydroxyl groups at the chain end of iPP-t-OH were measured by GPC and 1H NMR. Despite the high molecular weight and heterogeneous reaction, iPP-t-OH is effectively linked with PEG-t-NCO to produce di-blockcopolymers. DSC analysis of the di-blockcopolymer shows an obvious decrease in Tm and To, which indicated that PEG was successfully linked to the terminal end of iPP.
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