Synthesis and reactions of telechelic polyacetals

Abstract

Telechelic polyacetals have been synthesized by endcapping of bifunctionally living polyacetals with tertiary amines. Bifunctionally living poly‐(1, 3‐dioxolane) (poly‐DXL) was obtained by polymerization of the cyclic acetal initiated with terephthaloyl‐bis‐triflate. Attempts to prepare well defined bifunctionally growing poly‐DXL with trifluoro‐methane sulfonic acid anhydride failed. Low molecular weight dialkyl formals containing functional groups were used as transfer agents for the polymerization of cyclic acetals to control the molecular weight of the polymer and to introduce functional endgroups. Polytelechelic hydroxy‐terminated poly‐DXL was synthesized by copolymerization of DXL and glycidol. The latter monomer reacts as comonomer through its epoxy ring and as transfer agent by its hydroxyl group.

Segmented network structures for the separation of water/ethanol mixtures by pervaporation

“…21. BrieÑy, the cationic ring opening polymerization of DXL occurs at room temperature in dichloromethane with methyl triÑate as initiator and methylene bis(oxyethylacrylate) as transfer agent.…”

Hyperbranched aliphatic polyethers obtained from environmentally benign monomer: glycerol carbonate

“…5,6 Two different types of aliphatic hyperbranched polyethers have been obtained from latent AB 2 -type monomers. The polymerization of glycidol, which can be carried out according to anionic 7,8 or cationic 1,[9][10][11] mechanisms, leads to polyglycerol, and cationic polymerization of 3-ethyl-3-(hydroxymethyl)oxetane [12][13][14] to polytrimethylolpropane. However, the anionic polymerization of substituted oxetane has been recently reported.…”

Cationic polymerization of glycidol: coexistence of the activated monomer and active chain end mechanism

“…Only recently, Goethals reported on the cationic polymerization of glycidol, leading to branched polyols. 4 Polymerization of glycidol proceeding by the ACE mechanism would lead to the backbone composed exclusively of-CH2~CH(CH20H)-0repeating units; thus only primary hydroxyl groups should be present as substituents of the polyether chain:…”