Facile synthesis of acid mesoporous fluoropolymer as water-tolerant catalyst for esterification

Mesoporous fluoropolirmers with excellent hydrophobicity and acidity (H-PDVB-x-SSFAI) were solvothermally prepared by radical polymerization of perfluoroalkyl sulfonyl imide and divinylbenzene. The formation of mesopores depended on the synergy effect between nano-CaCO3 porogen and watered solvothermal media. The amount of doped water, and reactant ratio as well, was responsible for the textural properties. The fluoropolymers catalyzed the esterification of long-chain fatty acids with ethanol affording the conversion of 95%, along with TOF of 30.5 h(-1) (31.9 h(-1) reported for H2SO4). The high efficiency was attributed to its excellent hydrophobicity, Wettability for ethanol, and acidity. Stability trial evinced that the fluoropolymers were sufferable to 24 h water-boiling with 86% acid groups remained. These are promising recyclable fluoropolymers, maintaining fairly stable catalytic activity for esterification of acetic acid with pentanol at least 7 runs. (C) 2015 Elsevier Inc. All rights reserved.