Cationic Ring-Opening Polymerization of Five-Membered Cyclic Thiocarbonate Bearing an Adamantane Moiety via Selective Ring-Opening Direction

Abstract

A novel five-membered cyclic thiocarbonate bearing adamantane moiety, 4,6-dioxatetracyclo[6.3.1.1.3,1003,7]tridecane-5-thione (1), was synthesized from 1,2-adamantanediol and thiophosgene in the presence of pyridine. Monomer 1 underwent cationic ring-opening polymerization initiated by triethyloxonium tetrafluoroborate (Et3OBF4), methyl trifluoromethanesulfonate (TfOMe), trifluoromethanesulfonic acid (TfOH), and H2O with 2 mol % of boron trifluoride etherate (BF3OEt2) in CH2Cl2 at 30 °C to afford the polythiocarbonate by isomerization of the thiocarbonyl group into a carbonyl group with selective ring-opening direction. The number-average molecular weight and polydispersity of the polymer obtained by polymerization with H2O/BF3OEt2 were 10 600 and 1.44, respectively. The temperature with 5% weight loss of the obtained polymer was 338 °C. Monomer 1 expanded as large as 14% during the polymerization.

Effect of OH group on the water vapor sorption property of adamantane-containing polymer membranes

“…Recently, adamantane-containing polymers have been given much attention because they are expected not only to have high free volume but also to improve thermal stability, mechanical strength, optical property, and low dielectric property. Therefore, the effects of adamantyl unit on the physical and chemical properties, such as thermal, stiffness, optical, and electrical properties, have been widely investigated [22][23][24][25][26][27][28][29][30]. From these functions, the wide applications of adamantane-containing polymer materials, such as photo resistance [31,32], thermal stability and transparency [28,33], adhesion [30], separation of membrane materials [34][35][36] have been investigated.…”

Sulfur‐Containing Polymers

“…3.10 0 3.7 ]tridecane-5-thione, undergoes the cationic ROP to obtain the poly(monothiocarbonate) by isomerization of the thiocarbonyl group into a carbonyl group with selective ring-opening direction. The resulting polymer has good solubility and high thermal stability (310).…”

“…Segmented thiopolyurethanes prepared from thiodiol (138b) with x = 6 (440) and all thiodiols (138a) (310,311) as chain extenders, HDI (135a), and 20-80 mol% PTMO of M n = 1000 as the soft segment by one-step process in the same conditions as those for nonsegmented polymers are thermoplastic elastomers (except those based on 20% PTMO) showing partially crystalline structure. The polymers exhibit definite T g s (−70 to −60 • C) nearly independent of the hard segment content up to 50 wt% (40-80 mol% PTMO), indicating the existence of mainly microphase-separated soft and hard segments.…”

Superacid‐Catalyzed Reactions

“…[957][958][959][960][961] There has been a growing interest in poly(hydroxyalkanoates) and, in particular, polylactides as biodegradable and biocompatible polymers. 963 The cyclic thiocarbonate 290 undergoes a ring-opening polymerization into a poly(monothio)ester with the adamantane moieties in the backbone initiated by triflic acid 964 Polymerization of tetrahydrofuran to produce linear polyethers or cyclic oligomers is initiated by the protonation of the ring oxygen 965 (Scheme 5.97). 962 Polymerization was shown to occur selectively via acyl-oxygen cleavage [Eq.…”