Premium
Solid‐state graft polymerization of styrene in spherical polypropylene granules in the presence of TEMPO
Author(s) -
Sun Fangli,
Fu Zhisheng,
Deng Qingtian,
Fan Zhiqiang
Publication year - 2008
Publication title -
journal of applied polymer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.575
H-Index - 166
eISSN - 1097-4628
pISSN - 0021-8995
DOI - 10.1002/app.29415
Subject(s) - polymer chemistry , polymerization , polystyrene , polypropylene , grafting , tacticity , styrene , materials science , molar mass distribution , chemical engineering , chemistry , polymer , composite material , copolymer , engineering
A series of polypropylene‐ graft ‐polystyrene (PP‐ g ‐PS) were prepared by solid‐state graft polymerization of styrene (St) in the presence of tert ‐butyl perbenzoate (TBPB) and 2,2,6,6‐tetramethyl‐piperidinyloxy (TEMPO) using nascent spherical isotactic polypropylene (PP) granules as matrix. Reaction conditions such as ratio of TEMPO to TBPB, amount of TBPB and St, reaction time and temperature were investigated. The grafting degree (GD) decreased slightly with the addition of TEMPO, but the introduction of TEMPO reduced gel formation and degradation of PP chain. Introduction of camphor sulfonic acid in the TEMPO‐mediated grafting polymerization system lead to evident increase in molecular weight of PP‐ g ‐PS and decrease of gel formation with slight changes of GD. GPC curves of the product synthesized with TEMPO addition showed obvious tailing at high molecular weight end. Complex viscosity in dependence on angular frequency of the melt of product showed obvious shear‐thinning behaviors. All the experimental results indicated existence of long‐chain branches in the product of graft polymerization. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009