LAUSR

This manuscript studies the relation between macroscopic properties of the soy protein isolate (SPI)-based superabsorbent polymers (SAP) (e.g., water uptake capacity and tensile properties) and the extent of chemical modification conducted on the protein. The increase in the carboxyl group content, obtained from electrometric titrations, for acylated systems compared to native SPI brings with it an improvement in the protein hydrophilic character, as revealed by the determination of the water imbibing capacity. SEM images show that larger porous regions were developed in the acylated plastics. As for their mechanical properties, static tensile measurements indicated that acylated plastics with greater water uptake values display higher extensibility, compared to the reference sample. These natural-based SAP materials could be appropriate for applications in which maintaining the dimensional stability during service is not crucial (e.g. in agriculture and horticulture).