A preparation method of degradable polylactic acid tableware with strong hygroscopicity resistance

Abstract

The invention discloses a preparation method of degradable polylactic acid tableware with strong hygroscopicity resistance, which comprises the following steps: (1) sequentially adding coconut shell powder, nano-silicon oxide dispersion, and aspartic acid-lysine copolymer In the mixing mixer, after high-speed stirring, the modified coconut shell powder is obtained; (2) adding a lubricant to the hot melt adhesive, after mixing and stirring, the hot melt adhesive-lubricant mixture is obtained; (3) Polylactic acid and modified coconut shell powder are respectively vacuum-dried, and then polylactic acid, modified coconut shell powder, hot melt adhesive-lubricant mixture, crosslinking agent, and antioxidant are added to the Blended in a moment rheometer, and then molded in a flat vulcanizer to prepare degradable polylactic acid tableware. The degradable polylactic acid tableware prepared by the invention solves the defect of poor moisture resistance and moisture resistance of polylactic acid tableware products in the prior art, and does not wrinkle or crack after soaking in water for a long time.

Description

technical field [0001] The invention belongs to the technical field of polylactic acid material preparation, and in particular relates to a preparation method of degradable polylactic acid tableware with strong moisture absorption resistance. Background technique [0002] Plastic tableware dominates the disposable tableware market due to its advantages of light weight, low price, and good mechanical properties. However, it brings serious plastic white pollution while facilitating people's lives. When the rice is hot, 16 kinds of toxins will be produced. When using foam tableware or plastic bags to hold the hot fried dough sticks, the toxins have been inadvertently dissolved in the food. So far, a variety of non-polluting disposable tableware products have come out, which can be roughly divided into two categories: photodegradation and biodegradation. Biodegradation includes synthetic polymers and natural polymers. The latter The main raw materials are natural products, curr...

AI Technical Summary

Problems solved by technology

For example, the crystallinity of pure poly-L-lactic acid is about 60%, the glass transition temperature is 60°C, the melting point is 180°C, the tensile strength exceeds 70MPa, and the tensile modulus is greater than 3GPa. It has good rigidity and strength, but its fracture Elongation is only about 3%, prone to brittle fracture

PLA is a compostable, biodegradable, and renewable thermoplastic "green" polymer material, but PLA's low heat distortion temperature, high brittleness, and insufficient barrier properties limit its large-scale application in the field of tableware.

In the prior art, some organic or inorganic powders such as bamboo powder are used to enhance the polylactic acid material, and the enhanced polylactic acid material can effectively solve the above-mentioned problems, but in actual use, it is still found that the polylactic acid material It has the defect of poor moisture resistance and moisture resistance. After soaking in water for too long, the surface will wrinkle and the mechanical properties will deteriorate, which seriously affects the quality of polylactic acid materials.

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