Mechanism of the performance difference and effect of blow‐up ratio parameters on biodegradable poly (butyleneadipate‐co‐terephthalate)/polylactide composite mulch films

Abstract

The development and application of biodegradable mulching film is an efficient way to solve the “white pollution” of farmland. In the actual production, we found that the mulch film produced by different processing technology with the same formula showed quite different application properties. Here, the poly (butyleneadipate‐co‐terephthalate)/polylactide (PBAT/PLA) composite films with two die/screw diameters and eight blow‐up ratio were prepared by extrusion blowing. Results showed increasing blow‐up ratio can significantly improve the tensile strength at the transverse direction. In addition, the optical and water vapor barrier performances of the PBAT/PLA composite films were slightly effected. With the increasing of blow‐up ratio, the transverse molecular chain orientation of the polymer increases, resulting in changes in mechanical performance. This work can contribute to better understand the relationship between the performance and the manufacturing parameters of the biodegradable mulching films and foster the end‐user confidence in the eco‐friendly biodegradable mulch films.Highlights Eight PBAT/PLA mulch films with different blow‐up ratios were obtained. The properties of PBAT/PLA mulch films were mainly affected by blow‐up ratio. The relation between performance and manufacturing parameters was clarified. Die and screw diameter have no significant effect on film properties.