Akio Nakanishi

New industrial process of PTMG catalyzed by solid acid

Polymerization of THF catalyzed by solid acid in the presence of acetic anhydride was studied. A moderate Lewis acid catalyst produces required PTME (PTMG-acetate) having adequate M n . Zeolitic material is not suitable for this production because very high molecular weight PTME is co-produced. From this aspect, mixed oxide materials show good performance because only these have the required acidic character. Mass-transfer study suggests the importance of pore size of support and the homogeneity of active sites. They affect on the M n and the M w /M n strikingly. The commercial technology has established by utilizing these results.

92 New industrial process of PTMG catalyzed by solid acid supported on mesoporous material

Abstract Polymerization of tetrahydrofuran (THF) catalyzed by solid acid in the presence of acetic anhydride was studied. A moderate Lewis acid catalyst produced PTME (PTMG-diacetate) having appropriate molecular number (Mn). Zeolites were not suitable for this reaction because they produced PTME having very large Mn together. On the contrary, mixed oxide materials showed good performance. Py-IR result suggested that the acidic characters had an important role to control Mn. Mass transfer study suggested the importance of pore size of support and the homogeneity of active sites. They affected on the Mn and the polydispersity (Mw/Mn) strikingly. The commercial technology has been established by utilizing these results.