Facile metal‐free living cationic polymerization of various vinyl ethers by hydrogen chloride with ether

Synthesis of biocompatible and biodegradable block copolymers of polyvinyl alcohol‐block‐poly(ε‐caprolactone) using metal‐free living cationic polymerization

“…According to a previous article, HCl · Et 2 O initiating system allows to polymerize various vinyl ethers 13. The detailed polymerization mechanism has been described, which is the facile metal‐free method.…”

“…To meet these demands, no HCl/metal Lewis acid, for example, ZnCl 2 , EtAlCl 2 , SnCl 2 , initiating system but the HCl alone in diethyl ether (Et 2 O)13 was applied in the polymerization of vinyl ether polymers. Obtaining a material of desired properties led to the idea to try poly(ε‐caprolactone) (PCL) with a combination of polyvinyl alcohol (PVA)14 because both are completely biocompatible/biodegradable to nontoxic metabolites and well tolerated by tissues 15.…”

HCl·Et2O-Catalyzed Metal-Free RAFT Cationic Polymerization: One-Pot Transformation from Metal-Free Living Cationic Polymerization to RAFT Radical Polymerization1

“…Here, note that the addition of the proton to the VE (eq 6) is rapid. 19 However, the addition to a carbonyl group seems to be faster than that to an alkenyl group under this polymerization condition. Thus, eq 6 is considered to represent a negligible initiation process during the reactions of both cationogens at [IDTA or MOEA] 0 / [HCl] 0 ratios of 4.0−32.0/2.8 (mM).…”

“…Relationship between M n or M w /M n of poly(IBVE) and [HCl] 0 for MLCP using HCl·Et 2 O with either IDTA or MOEA in hexane at 0°C: [IBVE] 0 = 0.80 M, [IDTA or MOEA] 10.1021/acs.macromol.5b01071Macromolecules XXXX, XXX, XXX−XXX min 19. However, the polymerization with IDTA was found to progress slowly without an induction period and was completed in 24 h to afford soluble polymers in quantitative yields.…”

Halogen‐Bonding‐Mediated and Controlled Cationic Polymerization of Isobutyl Vinyl Ether: Expanding the Catalytic Scope of 2‐Iodoimidazolium Salts

“…[12] Alternatively, metal impurities that may be responsible for the degradation and coloration of polymers shouldb er educed or removed to produce high-quality materials commercially.I n light of this, the development of metal-free initiating system for the living cationic polymerization is in high demanda nd is as tate-of-the-artr esearch topic in the community of precision polymer synthesis. [17] As the former example, Webster [18] and Sugihara [19] have revealed the effectivenesso fs ulfide and ether additives to achievet he living cationic polymerization. [13][14][15] The addition of ammonium salts affected the polymerizations, and the optimizationo ft he counter anion resulted in living polymerizations.…”