Synthesis and Characterizations of Block Copolymer of Poly(n-butyl acrylate) and Gradient Poly(methyl methacrylate-co-N,N-dimethyl acrylamide) Made via Nitroxide-Mediated Controlled Radical Polymerization

Abstract

Methyl methacrylate (MMA)/N,N-dimethyl acrylamide (DMA) gradient copolymers with various chemical composition were synthesized by nitroxide-mediated controlled radical polymerization (NMP). Molecular weight (MW) characterization via gel permeation chromatography demonstrated that these materials were made in a “controlled” manner. The reactivity ratios values r 1(MMA) = 2.36 and r 2(DMA) = 0.33 were experimentally determined using the linear least-squares numerical method, results in good agreement with the literature. Characterization of the glass transition temperature, T g, by differential scanning calorimetry (DSC) of gradient copolymers exhibited one T g, with a value intermediate to the T g of pure poly(methyl methacrylate) (PMMA) and poly(N,N-dimethyl acrylamide) (PDMA). In contrast, di- and triblock copolymers made of poly(n-butyl acrylate) (PBA) as central block and PMMA/PDMA gradient copolymer as external block yielded two T g, one corresponding to the T g of PBA and the other intermediate to the T g of PMMA and PDMA, indicating microphase separation which was confirmed by dynamic mechanical analysis and TEM observations of films of di- and triblock copolymers showing lamellae structure.

Nanostructuration of Unsaturated Polyester by All‐Acrylic Block Copolymers, 1 ‐ Use of High‐Molecular‐Weight Block Copolymers

“…[36] Table 2 presents the molecular characteristics of P(MMA-co-DMA) random copolymers with same range of molar masses but different contents of DMA, as well as those of the PMMA, PDMA and PBA homopolymers. The corresponding characteristics of the triblock are shown in Table 3.…”

“…Molecular characteristics of the P(MMA-co-DMA) random copolymers and the different homopolymers, as determined by 1 H NMR analysis and SEC measurements (based on PS standards). [36] Polymer DMA M n PDI mol-% kg Á mol S1 [34] b) The values in brackets refers to UP precursors only, without S; c) From SEC measurements and based on PS standards; d) As determined by 1 H NMR analysis by comparing NMR spectra before and after styrene removal by evaporation; e) Ordelt reaction is the side reaction between -OH groups and the maleate double bonds during the UP prepolymer synthesis [35] Dynamic Mechanical Thermal Analysis (DMTA)…”

Synthesis of diblock and triblock copolymers from butyl acrylate and styrene by reverse iodine transfer polymerization

“…In recent years, controlled radical polymerizations (CRPs) have provided novel routes to synthesize well-defined low-polydispersity polymers with diverse architectures such as block, 1 graft, 1,2 or gradient 1,3 copolymers. The most well-known CRP techniques are nitroxide-mediated polymerization (NMP), 4 atom transfer radical polymerization (ATRP), 5 reversible addition-fragmentation chain transfer polymerization (RAFT), 6 and iodine transfer polymerization (ITP).…”

Application of Stable Radicals as Mediators in Living‐Radical Polymerization

“…An n-butyl acrylate macroinitator containing an alkoxyamine SG1 linkage on both ends was also synthesized and chain extended with methyl methacrylate and N, N -dimethyl acrylamide to give a triblock copolymer. 262 The RAFT and SFRP processes have been combined to make amphiphilic and thermosensitive graft copolymers, such as P(St-co-(p-CMS))-g-PNIPAAM. 263 Other amphiphilic block copolymers containing segments of monomethoxypoly(ethylene glycol) and polystyrene (MPEG-b-PS) using TEMPO have been reported by Shoaeifar et al .…”