Copper mediated controlled radical copolymerization of styrene and 2-ethylhexyl acrylate and determination of their reactivity ratios

Abstract

Copolymerization is an important synthetic tool to prepare polymers with desirable combination of properties which are difficult to achieve from the different homopolymers concerned. This investigation reports the copolymerization of 2-ethylhexyl acrylate (EHA) and styrene using copper bromide (CuBr) as catalyst in combination with N,N,N′,N″,N″- pentamethyldiethylenetriamine (PMDETA) as ligand and 1-phenylethyl bromide (PEBr) as initiator. Linear kinetic plot and linear increase in molecular weights vs. conversion indicate that copolymerization reactions were controlled. The copolymer composition was calculated using 1H NMR studies. The reactivity ratio of styrene and EHA (r1 and r2) were determined using the Finemann–Ross (FR), inverted Finemann–Ross (IFR), and Kelen–Tudos (KT) methods. Thermal properties of the copolymers were also studied by using TGA and DSC analysis.

Copolymerization of Styrene and Pentadecylphenylmethacrylate (PDPMA): Synthesis, Characterization, Thermomechanical and Adhesion Properties

“…The difference might also be due to the different initiating system employed; as the literature studies were performed using cobalt based initiating system [38]. Similar observation of initiating system influencing the reactivity was also observed by Koiry and Singha in the polymerization of styrene with 2-ethyl hexyl acrylate [47]. They suggested a difference in the polymerization mechanism of ATRP and conventional radical polymerization due to the difficulty in formation of the polar catalyst complex with monomers having non-polar side chain.…”

Design of Waterborne Asymmetric Block Copolymers as Thermoresponsive Materials

“…The morphology of the AB hard-soft block copolymers was further analyzed using Bruker Dimension Icon AFM (Bruker, Karlsruhe, Germany) using Olympus OMCL-AC160TS cantilever (Olympus, Hamburg, Germany) for tapping with a resonant frequency of 300 kHz and spring constant 42 N/m (34)(35)(36)(37)(38)(39)(40)(41)(42)(43)(44)(45)(46)(47)(48)(49)(50). Samples were cryocut at −80 • C.…”

“…The second monomer was fed without any removal of the unreacted styrene from the initial block. Considering the reactivity ratios were r1 (styrene) = 1.29 and r2 (2EHA) = 0.73 [49], the soft block was not expected to be pure poly(2EHA), but rather a gradient polymer that still incorporates some styrene units close Figure 2. Miniemulsion polymerization of the polystyrene "A" block using RAFT Agent BM1430: (a) conversion versus time; (b) number average molecular weight and dispersity versus monomer conversion and molecular weight distributions of (c) polystyrene (pSt)30 and (d) pSt50 obtained by RI refractive index detector in GPC.…”

“…The second monomer was fed without any removal of the unreacted styrene from the initial block. Considering the reactivity ratios were r1 (styrene) = 1.29 and r2 (2EHA) = 0.73 [49], the soft block was not expected to be pure poly(2EHA), but rather a gradient polymer that still incorporates some styrene units close to the A block and with the end of the chain richer in 2EHA. Nevertheless, the B block is named as p(2EHA) throughout the text for simplicity reasons.…”

“…Prior to the analysis of the morphology of the AB block copolymers having hard-soft domains by both TEM and AFM techniques, the theoretical prediction of the morphology obtained from the composition of the block copolymers and the map presented by Bates and Fredrickson (considering full segregation) [54] are presented in Table 3. The composition of the block copolymers was determined by NMR using the method explained by Singha et al [49] (the NMR spectra of the final block copolymers can be found in Figure S3). Only in the case of p(St50/2EHA50) did the theoretical morphology correspond to the lamellar one; for the rest, the cylinder morphology was expected.…”