Fuente: Journal of applied polymer Lugar: RESEARCH ARTICLE Process flow for producing Thermoplastic Agar/PBAT blending using a melt-mixing extruder, with applications in molded products.


ABSTRACT
This research examines a sustainable substitute for polyethylene through the application of marine-sourced agar in the form of thermoplastic agar (TPA). TPA was combined with polybutylene adipate terephthalate (PBAT) and modified using methylene diphenyl diisocyanate (MDI) as a compatibilizer. The bioplastic composites were processed via a twin-screw extruder. A thorough material characterization was conducted, encompassing Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), tensile testing, scanning electron microscopy (SEM), melt flow index (MFI), water absorption analysis, color assessment, and biodegradability evaluation. The addition of MDI markedly improved interfacial compatibility between TPA and PBAT, leading to an increase in tensile strength (from 8.65 to 16.02 MPa), elastic modulus, and resistance to water absorption and microbial degradation. The formulation containing 10% PBAT in the TPA/PBAT-MDI blend (TIP10%) exhibited the optimal equilibrium between mechanical performance and biodegradability, with tensile characteristics akin to those of low-density polyethylene (LDPE). The findings indicate that TPA/PBAT blends, especially when compatibilized with MDI, possess significant promise as biodegradable alternatives to standard polyethylene in packaging and related applications.