Plasticized starch-based biocomposites containing modified rice straw fillers with thermoplastic, thermoset-like and thermoset chemical structures

Hybrid mathematical modeling and multi‐objective optimization of mechanical properties of green composites based on starch and modified rice straw fillers

“…On the other hand, the use of benzylated RS pulp (BP) and benzylated RS (BR) with thermoplasticized structures in thermoplastic starch caused a considerable enhancement in the toughness and elongation at break of the starch/RS biocomposites. Higher starch/glycerol miscibility, improved chain flexibility of the RS products along with strong interfacial adhesion between fillers and starch matrix were the main reasons behind these findings 21 …”

“…As mentioned, the first step of RSM is to identify the design factors, based on the prior knowledge or data obtained from the screening. According to our recent study, three different types of modified lignocellulosic RS fillers have more profound impacts on the final properties of thermoplastic starch 21 . Thus, the loading of different RS‐based fillers including rice straw pulp (RP), benzylated rice straw (BR), and benzylated rice straw pulp (BP) were chosen as the design variables here.…”

“…The treated RS fillers were prepared in accordance with our previous work and chemical treatments including soda‐pulping and benzylation processes were applied accordingly on rice straw 21 . The regenerated RS‐based fillers used here are as follows: benzylated rice straw (BR), benzylated rice straw pulp (BP) and rice straw pulp (RP).…”

“…BP was prepared by subjecting RP filler to benzyl chloride and NaOH solutions concurrently, whereas BR was obtained by subjecting intact RS powder to these solutions. The interested reader is referred to our previous work, 21 for further information on the preparation procedures of these fillers. The mentioned biocomposites were prepared based on the thermoplastic starch containing 40 wt% glycerol plasticizer and 60 wt% thermoplastic starch.…”

“…These fillers had different chemical structures such as thermoset, semi‐thermoset, and thermoplastic ones. It was shown that the chemical modification of RS fibers and elimination of their thermoset structures led to a notable enhancement in the mechanical properties of the starch‐based biocomposites 21 . In fact, the obtained RS pulp (RP), containing micron‐sized cellulosic fibers, increased the modulus and tensile strength of the plasticized starch matrix even more than the untreated RS.…”