Synthesis of telechelic living poly(vinyl ethers)

Abstract

Reaction of ethyl vinyl ether (EVE) with an equimolar amount of hydrogen iodide (HI) in nonpolar solvents at -30 °C gave an adduct [CH3CH(OEt)I] (1) in quantitative yield. Similarly to the HI/I2 initiating system, 1, in conjunction with iodine, initiated living polymerization of a series of vinyl ethers in nonpolar media at -5 to -40 °C to give monodisperse polymers. Treatment of l,4-bis(vinyloxy)butane with 2 equiv of HI led to a diadduct [CH3CH(I)0(CH2)40CH(I)CH3] (2) quantitatively, under the conditions similar to those for the EVE/HI system. In the presence of 2 equiv of iodine, 2 acted as an effective bifunctional initiator that generated monodisperse, telechelic living poly(vinyl ethers) in nonpolar solvents at -40 °C. These bifunctional living polymers were capable of polymerizing vinyl ethers to give ABA-type triblock copolymers with a narrow molecular weight distribution in a high blocking efficiency; e.g., poly(methyl vinyl ether-b-hexadecyl vinyl ether-b-methyl vinyl ether). Telechelic poly(EVE) having sec-amino termini was obtained by quenching the living ends with n-butylamine. Chain extension using hexamethylenediamine as coupling agent led to poly(EVE) with in-chain amino ether linkages and a broad molecular weight distribution extending from 104 to 106.

ABC triblock polymethacrylates: Group transfer polymerization synthesis of the ABC, ACB, and BAC topological isomers and solution characterization

“…35 Aqueous GPC was performed using a Pharmacia Biotech ''Superdex'' 200 HR 10/30 GPC column Techniques like GTP and living cationic polymerization 36 allow only the polymerization of monomers containing a very hydrophilic stationary phase based on dextran covalently bound to highly crosswith similar chemistry and consequently similar reactivities. This precludes a large effect of the selinked porous agarose beads.…”

Near-monodisperse,n-alkyl, end-functionalized poly(methyl vinyl ether)s: Synthesis by living cationic polymerization and solution characterization

“…The advent of living cationic polymerization of vinyl ethers in 1984 4 enabled the synthesis of near-monodisperse homopolymers and block copolymers based on vinyl ethers, [5][6][7][8] including MVE. 9,10 In most studies, however, the focus has been on the synthesis rather than the aqueous solution characterization of the polymers.…”

Multifunctional Coupling Agents for Living Cationic Polymerization. 7. Synthesis of Amphiphilic Tetraarmed Star Block Polymers with α-Methylstyrene and 2-Hydroxyethyl Vinyl Ether Segments by Coupling Reactions with Tetrafunctional Silyl Enol Ether

“…11,16 Thus, when the conversion of RMeSt reached ca. 95% in 10 min, SiVE was added to a solution of the resultant living polymer 4 ([RMeSt] 0 ) [SiVE] 0 ) 0.20 M; [3] 0 ) 10 mM). The second-stage polymerization immediately ensued to give ca.…”