Experimental studies on the preparation and properties of starch-graft-poly(hexyl acrylate) copolymers

The preparation and the properties such as the chemical stability, solution properties, moisture absorption, ability to gelation, glass transition temperatures, thermal stabilities and the decomposition course of starch-graft-poly (hexyl acrylate) copolymers have been studied. In general, it can be said that as the grafting percent increases the chemical resistance in alkaline, inert, acidic and buffer environments, and the solubility in non-polar solvents of the copolymers increases. In turn, the solubility in polar solvents decreases compared to the solubility of starch. The T-g of starch-g-poly(hexyl acrylate) copolymers is in the range 102-133 degrees C and is much higher than Tg of poly(hexyl acrylate) homopolymer. The thermal stability of all tested copolymers is higher than 274 degrees C (inert conditions) and 230 degrees C (oxidative conditions). In inert conditions, all tested copolymers decompose in two main stages related to pyrolysis combined with the emissions of the following volatiles: CO, CO2, H2O, aldehydes, alcohols, acids, ester, furanes, aliphatic and alkene fragments. In turn, the copolymers decompose in main three stages in oxidative conditions. The emission of CO, CO2, H2O, aldehydes, alcohols, acids, aliphatic, furanes and alcohols as a result of pyrolysis, oxidation, decarboxylation, dehydration, and combustion processes was confirmed.

Automated summary

The preparation and properties of starch-graft-poly(hexyl acrylate) copolymers were studied, including chemical stability, solution properties, moisture absorption, gelation ability, glass transition temperatures, thermal stabilities, and decomposition course. It was found that as the grafting percent increases, the copolymers exhibit higher chemical resistance in various environments and increased solubility in non-polar solvents. However, their solubility in polar solvents decreases compared to starch. The copolymer's Tg is in the range of 102-133 degrees C, higher than that of poly(hexyl acrylate) homopolymer. The thermal stability of the copolymers is higher than 274 degrees C (inert conditions) and 230 degrees C (oxidative conditions). Decomposition of the copolymers in inert and oxidative conditions occurs in two main and three main stages, respectively, with the emission of various volatile compounds.