Statistical and Block Copolymers of Ethylene and Vinyl Acetate via Reversible Addition‐Fragmentation Chain Transfer Polymerization

Abstract

A dithiocarbamate chain transfer agent (CTA) based on Z‐group substituted with a diphenyl amine (–NPh2) moiety is selected for the synthesis of statistical and diblock copolymers of ethylene and vinyl acetate via reversible addition–fragmentation chain transfer polymerization. Benefiting from the good chain growth control of polyethylene (PE), poly(vinyl acetate) (PVAc), and poly(ethylene‐co‐vinyl acetate) (EVA) achieved with this CTA, linear diblock copolymers of the type EVA‐b‐PE, EVA‐b‐EVA, and PVAc‐b‐EVA are successfully synthesized. A three‐arm EVA star is additionally obtained starting from a trifunctional dithiocarbamate CTA.

Telechelic polyethylene, poly(ethylene-co-vinyl acetate) and triblock copolymers based on ethylene and vinyl acetate by iodine transfer polymerization

“…The shape of this signal evolves from a clean triplet to a broad signal with increasing the VAc content. Similar behaviors were already seen when synthesizing EVAs at different VAc contents by RAFT 33 and ITP. 35 Indeed, a terminal ethylene–iodine unit is less readily reactivated than a terminal VAc–iodine unit.…”

“…The experimental setup and conditions used to polymerize ethylene are similar to previous works from our group. [31][32][33][34][35] ITPs were conducted in a 160 mL autoclave reactor at 70 °C and at constant ethylene pressure (80 bar) in 50 mL of DMC. The ethylene consumption was determined gravimetrically after solvent evaporation.…”

“…Very recently, the use of a trifunctional dithiocarbamate offered the possibility to synthesize an original three-arm EVA star copolymer. 33 Even if control of ethylene polymerization has not yet been fully depicted by Co-mediated radical polymerization (CMRP), triblock and macrocycles based on ethylene and VAc have nevertheless been synthesized. 36–38…”

“…While the obtainment of well-defined copolymers with low ethylene incorporation have been reported, 29,30 progresses over ethylene controlled radical polymerization have only been made over the last ten years using RDRPs based on degenerative chain transfer process. These include reversible addition-fragmentation chain transfer (RAFT), [31][32][33] organotellurium mediated radical polymerization (TERP) 34 or iodine transfer polymerization (ITP) 35 techniques. These systems are now able to control the polymerization of ethylene and its copolymerization with vinyl acetate (VAc) to produce well-defined poly(ethylene-co-vinyl acetate) (EVA).…”

“…Very recently, the use of a trifunctional dithiocarbamate offered the possibility to synthesize an original three-arm EVA star copolymer. 33 Even if control of ethylene polymerization has not yet been fully depicted by Co-mediated radical polymerization (CMRP), triblock and macrocycles based on ethylene and VAc have nevertheless been synthesized. [36][37][38] Concerning ITP, the use of chain transfer agents (CTAs) with two active iodine atoms such as I-C 6 F 12 -I (CTA-1) reported in Scheme 1 has already been reported to prepare polymers bearing iodine at both polymer chain-ends by ITP.…”