Research On Forming Mechanism And Experiment Of Recycled Biological Packaging Materials With Starch And Pe

Recycled biological packaging material is a kind of biodegradable materials developing very fast in recent years. It can replace the white pollution and achieve the purpose of environmental protection. Research and application on the biological packaging material have become an inevitable trend in the development of packaging industry in the 21st century.This article on biological packaging materials by consulting the relevant literature and patents summarizes the current domestic and international overview of the development of bio-packaging materials and developes a program of preparation of bio-packaging material with starch, plant fiber, and polyethylene. In this paper, first, the forming mechanism of bio-packaging material was studied. Second, the flow field of extrusion and die were simulated by Adina software. According to results of the simulation, they were improved. Last, experimental platform was established for packaging materials which is prepared for a systematic experimental study.First, the scope of the main raw material was determined. Then, effects of starch, plant fiber, the amount of foam, screw speed, and barrel temperature on the material's mechanical properties were studied. Cushioning effect, moisture resistant, and degradation were investigated. Finally, response surface optimization of process parameters was made for finding the association between various factors and their impact on the material properties.The work and the main achievements in this thesis are as followed:1. This thesis studied the extrusion process, molding process, foaming process in forming mechanism of biological packaging materials, and formed a set of processing molding technology based on the mechanism of by current equipments.2. The single factor test identified the range of starch, plant fiber, polyethylene, foam blowing agents. The portion of starch is 50-70; the portion of plant fiber is 5-15; the portion of PE is 30-50 the portion of foaming agent is 1-3. Then how do screw speed, barrel temperature affect the material's mechanical properties and cushioning properties were studied.3. Water absorption of the material was studied. The study shows that the addition of the polyethylene improves a certain resistance to water absorption. Moisture agent can be greatly improved humidity resistant and anticorrosion performance of biological packaging material.4. A new approach for degrading biological packaging material is washing method. Through the washing method, the degradation rate of bio-packaging material can be accelerated, which can achieve the classification to reuse the recycal materials.5. Many factors were optimized with response surface method. Conclusions are as followed: extrusion temperature and screw speed is the main factors of influence tensile strength. The data were analyzed, and a statistical model was established about effects on the tensile strength. When screw speed is 100.73r/min; extrusion temperature is 118.14℃; the content of foaming agent is 2.75%; the content of filler is 5.62%, the tensile strength is biggest.