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Synthesis of stereoblock poly(methyl methacrylate) via transformation of isotactic‐specific living polymer anion to syndiotactic‐specific anion
Author(s) -
Kitayama Tatsuki,
Fujimoto Nobutaka,
Yanagida Takatsune,
Hatada Koichi
Publication year - 1994
Publication title -
polymer international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.592
H-Index - 105
eISSN - 1097-0126
pISSN - 0959-8103
DOI - 10.1002/pi.1994.210330207
Subject(s) - tacticity , methyl methacrylate , copolymer , polymer chemistry , materials science , polymer , polymerization , composite material
Polymerization of methyl methacrylate (MMA) by isotactic poly(methyl methacrylate) (PMMA) living anion, prepared with t ‐C 4 H 9 MgBr in toluene at −60°C, was carried out at −78°C in the presence of trialkylaluminiums (R 3 Al; R = CH 3 , C 2 H 5 , and n ‐C 4 H 9 ) to obtain a stereoblock PMMA, isotactic PMMA‐ block ‐syndiotactic PMMA. Among the R 3 Als, (CH 3 ) 3 Al gave most effectively the steroblock PMMA with narrow molecular weight distribution. The fraction of rr triad in the syndiotactic PMMA block increased with increase in the ratio of Al/Mg and reached about 76% at a ratio of Al/Mg ≥ 6. The method was also used to prepare stereoblock copolymer comprising isotactic PMMA block and syndiotactic block of butyl methacrylate. Stereocomplex formation and solution viscosity of the stereoblock PMMA were also studied.