Study on Blending of Degradable Resin

The blending of several fully biodegradable resins can make up for the respective shortcomings of single-component fully biodegradable materials without affecting the degradation performance of the material. It provides a fully biodegradable material with excellent mechanical properties and processing properties that can replace general plastics. reference.

Butylene succinate (PBS) has good biodegradability, and the large amount of methylene structure in the main chain makes it have mechanical and physical properties similar to general polyethylene materials, suitable for blown films and hollow containers, Extrusion processing of sheet, spinning, injection molding and other processing techniques can be used to prepare a variety of fully biodegradable polymer products. However, the general PBS has low molecular weight, low processing temperature and low viscosity, and the mechanical properties of the prepared material cannot be compared with PE, and blending modification studies are required. Moreover, polybutylene succinate is expensive, and its application and promotion are restricted.

Polylactic acid (PLA) is a synthetic polymer material with excellent biocompatibility and biodegradability. Polylactic acid products can be completely decomposed into CO2 and H2O after being discarded, so it is a completely natural recycling type biodegradable material. However, PLA has many shortcomings in performance, such as brittleness, poor impact resistance, poor processing thermal stability and gas barrier properties. At present, a variety of small molecule toughening agents are used as processing aids for PLA, and the toughening effect is very good. However, with changes in environmental conditions such as temperature and humidity, small-molecule tougheners will migrate out of the product, thereby reducing the performance of the product.

PLA/PBS has a certain degree of compatibility, PLA/PBS blend is a partially compatible blend system. In the process of melt blending, a certain degree of transesterification occurred between the polyester components in the blending system, which improved the compatibility of the blending system. PLA has high modulus and tensile strength, but low elongation at break and poor toughness; while PBS has strong flexibility, but its tensile strength and modulus are lower than PLA. It is blended with PLA and PBS. An effective way to improve the toughness of PLA.