Protein-Intercalated Bentonite as Nano-Reinforcement in Bloodmeal-Based Bioplastics

Abstract

Novatein Thermoplastic Protein (NTP) is a biopolymer produced by modifying bloodmeal to a thermoplastic material, but requires reinforcement to improve mechanical properties. Proteinintercalated calcium (CaBt) and sodium bentonite (NaBt) were investigated as nano-scale reinforcements in NTP. These were prepared by recovering proteins from meat processing wastewater called stickwater, thereby reducing treatment cost and intercalating protein into clay layers in a single step. Using stickwater-modified NaBt improved the composite’s tensile strength by 23% (at 0.5 parts per hundred bloodmeal, pphBM) and Young’s modulus by 17% compared to standard NTP. Stickwater treatment greatly improved the compatibility of bentonite with NTP compared to gelatin-treated bentonite whose resulting composites only had similar or slightly improved mechanical properties. The improved mechanical properties are parallel with other improvements observed in thermal, crystallinity and filler distribution. Potential applications include plant pots and seedling trays for plant nursery and agricultural disposable tools such as weasand clips, nails and barbs.