Full-biodegradable composite film and preparation method thereof

Abstract

The invention belongs to the technical field of polymer materials, and particularly relates to a full-biodegradable composite film and a preparation method thereof. The composite film is prepared from the following raw materials: polylactic acid, polyethylene glycol, citrate, ultrafine wool powder, a solubilizer, ultrafine zeolite powder, ultrafine aluminum powder, ultrafine vesuvianite powder, silicone oil and phosphite ester, is resistant in temperature, tearing and stretching, can be completely biodegraded, does not pollute environment, and has the characteristics of antibacterial property, good transparency, high glossiness and the like. The composite film can be used in the field of packaging bags, particularly in foods, daily necessities farmlands, shopping bags and the like. The preparation method adopts a three-layer co-extrusion casting film technology, can perform molding through a quenching roll, is high in accuracy, and can sufficiently exert performance of a processed material; and the size accuracy, optical performance, thickness uniformity and the like of the film can be guaranteed due to each process and parameter.

Description

technical field [0001] The invention belongs to the technical field of polymer materials, and in particular relates to a fully biodegradable composite film and a preparation method thereof. Background technique [0002] At present, the research and development of biodegradable plastics is mainly based on starch-based biodegradable plastics, and the main products are starch products added or blended with polyolefin or polystyrene. However, this starch / plastic blend does not achieve true complete biodegradation, but only breaks down the polymer into pieces, which still has a large impact on the environment. [0003] Polylactic acid (PLA) is a completely environmentally friendly biodegradable material with good mechanical properties and biodegradability. The raw materials come from a wide range of sources, including corn, wheat, tapioca and other starches as the initial raw materials. Its application in the field of packaging has important practical significance. It is easil...

AI Technical Summary

Problems solved by technology

The Chinese invention patent with the application number 201110129543.X discloses a method for preparing waste gas wool / polylactic acid ecologically compatible materials. The composite material prepared by this method can be completely biodegradable, but the composite material prepared by this method is not very good. Good to improve the mechanical properties of polylactic acid, the compatibility of polylactic acid and wool is poor, which limits its good application in the field of packaging materials

The Chinese patent application with the application number 201110292129.0 discloses a fully biodegradable keratin fiber reinforced and heat-resistant modified polylactic acid material and its preparation method. The raw materials used in this method include wool, cow hair, sheep horn, etc. Modified keratin fibers are obtained, and the modified polylactic acid material prepared by this method does not improve the strength and flexibility of polylactic acid well, and its elongation at break and impact strength cannot meet the requirements

[0006] At present, the main problems hindering the application of biodegradable polylactic acid are hard and brittle performance, low impact strength, poor toughness at low temperature, and high molecular weight polylactic acid is difficult to degrade.