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The production of biobased copolymers such as poly­(styrene-co-butyl acrylate-co-methacrylic acid) for paints and coating applications is indispensable for the establishment of sustainable biorefineries, but it is challenging because of the utilization of fossil-based sources for the syntheses of methacrylic acid (MAA) from biomass. We have studied the catalytic decarboxylation of biobased itaconic acid, citric acid, and aconitic acid to MAA. Among different tested catalysts, the spinel BaAl12O19 chemical substance was found to grant an additional active catalysis, it optimized selectivity, and a 50% synthesis yield of MAA was achieved. The as-synthesized MAA vinyl monomer has been consequently utilized for the production of a chain-growth poly­(St-co-BA-co-MAA) copolymer, industrially manufactured for coating, adhesive, and paint end-user applications. The latexes’ physical properties of bio-MAA-incorporated structured polymers have also been compared with a copolymerized commercial poly­(St-co-BA-co-MAA) terpolymer, fabricated from petroleumbased MAA. The functional group distribution, measured molecular weight (M w), determined polydispersity index (Đ M), glass transition temperature (T g), and integrated solid content (w S) of copolymerization poly­(St-co-BA-co-MAA) constituent units were comparable with benchmarks.

Semibatch, power feed, and shot‐addition feeding strategies were employed to synthesize carboxylated latex under acidic conditions, using emulsion polymerization. As a source of carboxyl groups, acrylic (AA) or methacrylic acid (MAA) was used. The distribution of carboxyl groups between feeding strategies were investigated using rheology, potentiometric/conductometric titrations, transmission electron microscopy, and FT‐IR spectroscopy. Upon alkalization, particle swelling was observed using dynamic light scattering. With increasing pH, both the AA‐ and MAA‐based latexes showed significant increase in hydrodynamic diameter as a consequence of the dissociation state of carboxyl groups. However, only MAA‐based latexes exhibit very pronounced increase in viscosity and storage modulus, and were therefore characterized as gels. The effect of feeding strategies was found to be more pronounced with the MAA functionalized latexes. By employing mentioned three procedures, significant differences in the rheological behavior of the neutralized dispersions were detected. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42062.

Chemical and physical parameters of the aqueous polyurethane dispersion (PUD) were studied after the synthesis. A prepolymer mixing process with a limited-chain extension step was used in order to examine the polymer and dispersion behavior with respect to the ageing time. Measurements of free isocyanate groups were performed with the aid of Fourier transform infrared spectroscopy (FT-IR). The pseudo-first-order kinetics of NCO disappearance was proposed and the value of the corresponding constant was determined. Additionally, particle size, particle size distribution, pH, conductivity and molecular mass were monitored and compared. Keywords: polyurethane dispersion, colloid, FT-IR V raziskavi smo preu~evali spreminjanje kemijskih in fizikalnih parametrov vodne poliuretanske disperzije (PUD) po sintezi. Disperzijo smo sintetizirali po postopku vme{avanja prepolimera z omejenim podalj{evanjem verig za preu~evanje polimerne disperzije z ozirom na~as po sintezi. Merjenje prostih izocianatnih skupin smo izvedli z metodo Fourierjeve transformacijske infrarde~e spektroskopije (FT-IR). Predpostavili smo kineti~ni model psevdoprvega reda z ozirom na reakcije izocianatnih skupin ter dolo~ili vrednost kineti~ne konstante. Dodatno smo spremljali in primerjali povpre~ne velikosti delcev, porazdelitev velikosti delcev, pH, prevodnost in molekulsko maso.

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