A hybrid mathematical modeling/optimization approach based on theresponse surface methodology (RSM) and desirability function (DF) capabili-ties was applied here to imitate and optimize the mechanical properties ofthermoplastic starch-based biocomposites. In order to prepare the biodegrad-able and renewable biocomposites, rice straw (RS) was chemically modified toobtain more effective sustainable reinforcing fillers for starch, having semi-thermoset and core-shell structures. A combination of different RS productswas used in the biocomposites and the composition of RS-based fillers waschosen as control variable. A series of experiments, by using RSM, weredesigned to assess the effects of filler loading and composition on the Youngmodulus, tensile strength, ultimate strain, and absorbed energy of the bio-composites. The best-fitting regression functions were identified via RSM sta-tistical analysis and transformed into DF to optimize the desired responsesconcurrently. The findings demonstrate that the starch/RS product bio-composites with optimum elastic modulus (339.3 MPa), tensile strength(9.8 MPa), elongation at break (13.8%), and absorbed energy (1831.2 kJ/m2)were obtained by incorporating RS-based fillers with both semi-thermoset andcore-shell structures in combination with each other at loadings of 13.5 and6.5 phr, respectively.

Keywords