Mesoporous Zeolite as a New Class of Catalyst for Controlled Polymerization of Lactones
Autor: | Takashi Tatsumi, Takuzo Aida, Keisuke Kageyama, Shin-ichi Ogino |
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Rok vydání: | 1998 |
Předmět: | |
Zdroj: | Macromolecules. 31:4069-4073 |
ISSN: | 1520-5835 0024-9297 |
Popis: | Polymerization of lactones such as δ-valerolactone (VL) and e-caprolactone (CL) with protic compounds proceeded in the presence of an aluminosilicate mesoporous zeolite Al−MCM-41 (pore diameter of 27 A, surface area = 1010 m2 g-1, and Si/Al = 17), to give polyesters with a narrow molecular weight distribution. A sequential two-stage polymerization of VL and CL with Al−MCM-41/butanol gave a block copolymer. NMR and GPC studies showed that the produced polymer carries a terminal group originating from the protic compound. In contrast with Al−MCM-41, pure silicate MCM-41, an MCM-41 with masked SiOH functionalities, and a “microporous” aluminosilicate with much narrower pores (zeolite-Y; pore diameter = 8 A) were not effective for the polymerization under similar conditions. Infrared spectroscopy of an inclusion adduct of Al−MCM-41 with VL suggested a possible interaction of the monomer onto the aluminosilicate surface. Al−MCM-41, isolated from the polymerization mixture, could be used again for the polymeriz... |
Databáze: | OpenAIRE |
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