Efficient synthesis of poly(oxymethylene) dimethyl ethers over PVP-stabilized heteropolyacids through self-assembly  

作　　者：Xiaolong Fang Jin Chen Linmin Ye Haiqiang Lin Youzhu Yuan 

机构地区：[1]State Key Laboratory of Physical Chemistry for Solid Surfaces, National Engineering Laboratory for Green Chemical Productions of Alcohols,Ethers and Esters, College of Chemistry and Chemical Engineering, Xiamen University

出　　处：《Science China Chemistry》2015年第1期131-138,共8页中国科学（化学英文版）

基　　金：financially supported by the National Basic Research Program of China(2011CBA00508);the National Natural Science Foundation of China(21173175,21303141);the Research Fund for the Doctoral Program of Higher Education(20110121130002);the Program for Changjiang Scholars and Innovative Research Team in University(IRT1036)

摘　　要：A series of polyvinylpyrrolidone-stabilized heteropolyacids(PVP-HPAs)are generated by self-assembly of HPAs and PVP in methanol.The PVP-HPAs are then employed as catalysts for the synthesis of poly(oxymethylene)dimethyl ethers(DMMn,n1)by the methanolysis of trioxane.The results suggest that the acidity of PVP-HPAs is tunable by changing the ratio of PVP and HPAs,which is a key factor for the selectivity of the DMMn product.By optimizing the composition and reaction conditions,two types of PVP-HPA,PVP-phosphotungstic acid(PVP-HPW)in a PVP/HPW ratio of 1/4:1 and PVP-silicotungstic acid(PVP-HSi W)in a PVP/HSi W ratio of 1/4:3/4,respectively afford 52.4%and 50.3%yields of DMM2–5.The optimized catalysts are reusable for a minimum of 10 times without a significant drop in performance.A series of polyvinylpyrrolidone-stabilized heteropolyacids （PVP-HPAs） are generated by self-assembly of HPAs and PVP in methanol. The PVP-HPAs are then employed as catalysts for the synthesis of poly（oxymethylene） dimethyl ethers （DMMn, n≥1） by the methanolysis of trioxane. The results suggest that the acidity of PVP-HPAs is tunable by changing the ratio of PVP and HPAs, which is a key factor for the selectivity of the DMMn product. By optimizing the composition and reaction conditions, two types of PVP-HPA, PVP-phosphotungstic acid （PVP-HPW） in a PVP/HPW ratio of 1/4：1 and PVP-silicotungstic acid （PVP-HSiW） in a PVP/HSiW ratio of 1/4：3/4, respectively afford 52.4% and 50.3% yields of DMM2-5. The optimized catalysts are reusable for a minimum of 10 times without a significant drop in performance.

关 键 词：poly（oxymethylene） dimethyl ethers METHANOL TRIOXANE HETEROPOLYACIDS POLYVINYLPYRROLIDONE 

分 类 号：O632.4[理学—高分子化学]