Combining ATRP of Methacrylates and ROP of L,L‐Dilactide and ε‐Caprolactone

Abstract

Coupling atom transfer radical polymerization (ATRP) and coordination‐insertion ring‐opening polymerization (ROP) provided a controlled two‐step access to polymethacrylate‐graft‐polyaliphatic ester graft copolymers. In the first step, copolymerization of methyl methacrylate (MMA) and 2‐hydroxyethyl methacrylate (HEMA) was carried out at 80 °C at high MMA concentration by using ethyl 2‐bromoisobutyrate and [NiBr2(PPh3)2] as initiator and catalyst, respectively. Kinetic and molar masses measurements, as well as 1H NMR spectra analysis of the resulting poly(MMA‐co‐HEMA)s highlighted the controlled character of the radical copolymerization, while the determination of the reactivity ratios attested preferential incorporation of HEMA. The second step consisted of the ROP of ε‐caprolactone or L,L‐dilactide, in THF at 80 °C, promoted by tin octoate (Sn(Oct)2) and coinitiated by poly(MMA‐co‐HEMA)s obtained in the first step. Once again, kinetic, molar mass, and 1H NMR data demonstrated that the copolymerization was under control and started on the hydroxyl functions available on the poly(MMA‐co‐HEMA) multifunctional macroinitiator.Comparison of the SEC traces for the poly(MMA‐co‐HEMA) macroinitiator P2 (line only), the polymethacrylate‐g‐PLA copolymer C2 (line marked by ○), and the polymethacrylate‐g‐PLA C3 (line marked by ▵).magnified imageComparison of the SEC traces for the poly(MMA‐co‐HEMA) macroinitiator P2 (line only), the polymethacrylate‐g‐PLA copolymer C2 (line marked by ○), and the polymethacrylate‐g‐PLA C3 (line marked by ▵).

Synthesis of poly(ɛ-caprolactone)-block-poly(n-butyl acrylate) by combining ring-opening polymerization and atom transfer radical polymerization with Ti[OCH2CCl3]4 as difunctional initiator: I. Kinetic study of Ti[OCH2CCl3]4 initiated ring-opening polymerization of ɛ-caprolactone

“…Meanwhile, ATRP has been proved to be efficient to synthesize polymer with desired macromolecular architectures [33][34][35][36]. Therefore, it is very interesting to combine ROP and ATRP to synthesize PCL-based copolymers with controlled length, composition, and architecture of polymer chains [37][38][39][40].…”

Branched aliphatic polyesters by ring-opening (co)polymerization

“…Using this methodology, graft copoly(ester-vinyl alcohol) [27,[141][142][143][144][145], copoly(ester-amine) [146], copoly(ester-acrylate) [42,147] and polyester grafts on polysaccharides [148][149][150][151][152] have been obtained.…”

“…Duda and Dubois used the "grafting from" technique for the synthesis of graft copolymers using MMA/HEMA copolymer as a backbone with pendant initiating -OH groups for ε-caprolactone and lactide polymerization (toluene as a solvent, 80°C, Sn(Oct) 2 as a catalyst) [147]. …”

Block and Graft Copolymerization by Controlled/Living Radical Polymerization Methods

“…Recently, many studies have been reported in the literature about the synthesis of macromolecules with various compositions (homopolymers, random, periodic, block, graft and gradient copolymers) and novel topologies (linear, star, comb, branched, hyper branched, networks, brushes etc.) using CRP techniques [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30]. It is observed that the significant improvement in block and graft copolymer synthesis has become with development of controlled/living radical polymerization (CRP) techniques.…”