Microstructure study of styrene/n-butyl acrylate emulsion copolymers by 13C nuclear magnetic resonance spectroscopy

Polystyrene-block-poly(butyl acrylate) and polystyrene-block-poly[(butyl acrylate)-co-styrene] block copolymers prepared via controlled free-radical miniemulsion polymerization using degenerative iodine transfer

“…On the other hand, the composition microstructure of the second block was determined by 13 C NMR with the help of previously published data on peak assignments for the various triads. [13] The conclusions are illustrated in Fig. 5 and confirm the tapered structure of the poly[styrene-co-(butyl acrylate)] second block.…”

“…For instance, as in bulk, the overall rate of St and BA emulsion copolymerization is much lower than the rate of BA homopolymerization. [12] Moreover, the reactivity ratios below 1 (r BA = 0.18; r St = 0.66 in emulsion [13] ) ensure the incorporation of styrene as isolated units when a small proportion of this monomer is used, which should not drastically modify the properties of the poly(BA) block. This latter is expected to exhibit a tapered structure with an increasing proportion of BA towards the x-end of the chain.…”

Chemical heterogeneity analysis of high-conversion poly[styrene-co-(ethyl acrylate)]s by NMR and on-line coupled SEC-NMR

“…This can be due to the poor accuracy in the quantitative analysis of the experimental data or due to specifics of polymerization kinetics. Similar effects have been reported by Llauro-Darricades et al, who investigated the microstructure of styrene/ butyl acrylate emulsion copolymers by 13 C NMR 23) . They also obtained significant discrepancies between simulated and experimental data for acrylate centered triads in case of high butyl acrylate concentration.…”

Synthesis of Polystyrene-block-poly(butyl acrylate) Copolymers Using Nitroxide-Mediated Living Radical Polymerization in Miniemulsion

“…1 H NMR spectroscopy showed the copolymer exhibits the expected composition (49.75 mol-% styrene units versus 50.25 mol-% BuA units), providing further evidence of the absence of homopolymer. The copolymer microstructure was analyzed by means of 13 C NMR spectroscopy (PS quaternary carbon: 144.5 to 146.6 ppm; PBuA carbonyl group: 174.0 to 176.0 ppm [25] ). Two main triads corresponding to the SSS and AAA units (S: styrene and A: BuA) were observed.…”