Investigation of Methyl Methacrylate Grafting on Model Single Fatty Acid Alkyds

Abstract

Four model alkyds were prepared by the fatty acid process using a single fatty acid (stearic, oleic, linoleic, or linolenic acid) with phthalic anhydride and glycerol. These model alkyds were reacted with methyl methacrylate (MMA) in the presence of benzoyl peroxide or azobis(isobutyronitrile). 1 H NMR, 2D gradient heteronuclear multiple quantum coherence NMR, matrix assisted laser desorption ionization mass spectrometry, solvent extraction, and gas chromatography were used to evaluate each model alkyd system. The conversion of MMA was quantified, and the grafting mechanism of MMA onto each model alkyd was elucidated. In general, both polymerization rates and MMA conversions were inhibited in the presence of alkyd resins. For oleic alkyd model systems, the grafting site was primarily located at the double bond on the fatty acid chain. Both the homopolymerization and copolymerization of the MMA are significantly retarded by chain transfer of the hydrogen from the double allylic site in the linoleic and linolenic model systems. For the linoleic alkyd and linolenic alkyd model systems, the grafting reaction predominately occurred at the activated double allylic methylene group on the fatty acid chain via hydrogen abstraction by the primary radical and MMA radical, followed by grafting in a termination reaction with a propagating MMA radical.

Hybrid alkyds, the glowing route to reach cutting-edge properties?

“…Thereby, fatty acids, polyols and polyacids are added together and react through esterification reaction (Scheme 4). 4,8,34 Scheme 4: Polymerization of alkyd resin using fatty acids…”

Lignin nanoparticles modified with tall oil fatty acid for cellulose functionalization

“…The reactivity of different unsaturated fatty acids and TOFA based materials in grafting reactions, for example, with acrylic monomers has been studied, when so-called alkyd-acrylic copolymers and hybrid material have been prepared. It has been shown that both the isolated double bonds of oleic acid and the double allylic sites of linoleic and linolenic acids are reactive in free radical grafting reactions with monomers such as methyl methacrylate or butyl acrylate (Uschanov et al 2008;Wang et al 2018).…”

“…The TOFA and fatty acid esters of lignin have been synthetized to produce novel lignin-based products, for example, for coating of paper boards and to improve board properties (Hult et al 2013), or to improve compatibility of lignin with polystyrene (Pawar et al 2016). TOFA compounds contain reactive double bonds that can be utilized for grafting purposes (Uschanov et al 2008;Rämänen and Maunu 2014;Wang et al 2018). Lignin esters of maleic acid or trans-2-butenoic acid (crotonate) derivatives have also been used for improving the reactivity of lignin towards cross-linking and grafting reactions in thermal processes (Hu et al 2014;Luo et al 2018).…”