The effect of a blowing agents that affected Polylactic acid (PLA) and Epoxidized natural rubber (ENR) the blowing agents composed of citric acid (CA) and sodium hydrogen carbonate (NaHCO3) mixing by twin screw extruder with co-rotation screw. The properties of biodegradable foams were investigated. Blended foams of all composition were prepared by using compression molding at 200°C using different proportions of PLA, ENR, CA and NaHCO3. Mechanical properties of the samples were characterized by using universal testing machine. Thermal properties including Glass transition temperature (Tg), crystallization temperature (Tc) and melting temperature (Tm) were examined by using differential scanning calorimetry (DSC). Physical properties including morphology and density of blended foams were also investigated and morphological properties were studied with a scanning electron microscope (SEM).

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The present research aimed to develop biodegradable mulch films that could resolve the environmental problem in agriculture. The research also compared the properties of transparent and black commercial mulch films. Blended films were prepared by blown-film extrusion, heating at 170 °C, and rotation at 55 rpm. The results revealed that the appearance of FTIR spectra were shown as functional groups of PBAT, described at 1710 cm-1 and 1267 cm-1, which corresponds to carbonyl groups in ester linkage and C-O in ester linkage, respectively. The presence of O-H carboxylic acids, attributed within the range 910-950 cm-1. The films containing 10% PLA loading showed peaks from 937 to 1712 cm-1, more than films containing 20% PLA loading. The carbon black contained in the biodegradable film could interrupt the mobility of the polymer chain, leading to decreased Tm, while the incorporation of carbon black in biodegradable mulch films could increase the tensile properties of blends.

The aim of this study was to characterize thermoplastic starch containing corn starch and tapioca residues, which were used as reinforcement in a blended matrix. In the process, the composites were prepared with different tapioca residue contents at 20, 30, 40, 50 and 60 % by weight using compression molding at 135 °C for 8 min. Subsequently, their mechanical, thermal and morphology properties were evaluated. The results showed that the reinforcing effect of tapioca residue lead an increase in the stiffness of the samples. Young’s modulus increased with higher tapioca residue content. When the loading of tapioca residue increased tensile strength for 80/20 and 70/30 mixtures from 7.46 to 8.58 MPa. In addition to the highest of tapioca residue could increase tensile strength dramatically. Further, the glass transition temperature tended to decrease with the increased loading of tapioca residue. Moreover, the morphology showed that the increment of tapioca residue content appeared embedded in the polymer matrix.