New highly efficient initiators for the copolymerization of 1,3‐dioxolane with 1,3,5‐trioxane based on the derivatives of trifluoromethanesulfonic acid

Abstract

A successful initiator for the preparation of a copolymer of 1,3,5-trioxane (1) with 1,3-dioxolane (2) which is further designed for practical uses should not only be able to give sufficiently high polymerization rates and polymerization degrees but also produce a polymer with a low content of the unstable fraction. Although it is known that these parameters as well as the copolymer structure l ) (tendency of the formation of blocks) depend on the initiator used, the reasons of these dependences are not yet fully understood. n 0 0 \o/ CH 1 2 3 F,CS020CHzOCH2CHzOSO~CF3 6Recently we have shown that in the homopolymerization of 2 with triphenylmethyl salts bearing various anions, both the rate of polymerization and the polymerization degree depend on the anion structure This dependence is due, at least in the homopolymerization of 2, to the lability of some of the anions. With the most unstable ones (e.g. SbC1;) no polymerization proceeds at all and j?-chloroethyl formate and SbC13, formed upon the decomposition of the 1,3-dioxolanylium tetrachloroantimonate, are the sole reaction products of the system consisting of triphenylmethylium tetrachloroantimonate and 2 in CH,Cl, as solvent. 243

Activated Monomer Mechanism (AMM) in Cationic Ring-Opening Polymerization. The Origin of the AMM and Further Development in Polymerization of Cyclic Esters

“…55,57 Triflic acid, belonging to the strongest acids, was used first in CROP a long time ago (1973), namely, in CROP of THF and cyclic acetals (the least basic among cyclic monomers). 86 Most probably TfOH is (or was) used (in ppm concentration) in industrial CROP of 1,3,5-trioxane, leading to the high molar mass thermoplastic polyacetal.…”

Poly(alkylene oxide) Ionomers. II. Solution Co- and Terpolymerization of Trioxane for the Preparation of Poly(oxymethylene) Ionomers

“…Penczek and coworkers 15 have shown that the best results, i. e., short induction periods, high polymerization rates, high degrees of polymerization and a low content of unstable fraction, comparable with other POM copolymers, have been obtained when TO was copolymerized with DO in the presence of the ester or anhydride derivatives of TFS. The excellent performance of these systems as cationic initiators was ascribed to the low nucleophilicity and stability of the CFaSOzoe anion.…”

“…Table VII shows a comparison of the results for the copolymerization of TO with DO in the presence of TFS, its anhydride or other types of cationic initiators. The copolymerizations 15 were conducted at 60°C in cyclohexane as the solvent and in the presence of 2.0 weight percent (sum of Table VII were carried out for three hours except for the one initiated with the triphenyl methylium salt (AsFs8 anion) which lasted for two and a half hours. The base stabilization of some copolymers was carried out in benzyl alcohol at 150°C in the presence of tri-n-butylamine for 30 min.…”

A kinetic study of the acceleration effect of substituted benzyl alcohols on the cationic photopolymerization rate of epoxidized natural oils

“…Penczek and Kubisa [17,18] have shown that in the presence of alcohols, the polymerization rate of epoxide monomers can undergo an acceleration effect. They have proposed an 'activated monomer mechanism'.…”