Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1403042 | European Polymer Journal | 2008 | 4 Pages |
Isotactic 6-armed star-shaped poly(vinyl alcohol) (PVA) with a narrow molecular weight distribution was successfully prepared by the living cationic polymerization of 6-armed star-shaped poly(tert-butyl vinyl ether) (PTBVE) and subsequent acidic ether cleavage. The PTBVE was synthesized using hexa(chloromethyl) melamine (HCMM) as a hexafunctional initiator and ZnI2 or ZnCl2 as an activator in toluene/MC (1/1 v/v) at −70 °C. A better living stability of PTBVE was obtained in the ZnCl2 activator system. The number average molecular weight and the polydispersity index of the 6-armed star-shaped PTBVE polymerized with ZnCl2 at −70 °C for 24 h were 156,000 g/mol and 1.47, respectively. The fraction of the mm sequence of the resulting PVA was 52%.