Study On Preparation Of High Strength Molding Packaging Materials From Straw Fiber

Under the premise of national policies and the international environment,the demand for green packaging materials is huge,and pulp molding is developing rapidly.However,the national policy restricts harvesting,and a large amount of wood and waste paper rely on imports,which seriously restricts the development of pulp molding materials in China.Therefore,it is urgent to find a substitute raw material.This paper combines the basic national conditions of China,using straw straw as the main raw material,optimizes the preparation process of molded packaging materials,and simulates the performance of straw molded products.The main research contents and conclusions are as follows:The effect of alkali amount,liquid ratio,holding time and cooking temperature on the tensile and bending properties of molding materials during the pulping process was investigated by single factor experiment.The results showed that the material had the best performance under the conditions of cooking temperature of 100?,liquid ratio of 1:5,alkali content of 8%and holding time of 90 min.The index was:the crude pulp yield was 73.97%.The crack length is 6254.05m,the bending strength is 76.13MPa,and the elastic modulus is 6813.71 MPa.The experiment was confirmed by the verification experiment to be reproducible.Compared with wood residue,waste paper pulp and untreated straw,the results show that the molded material prepared by straw pulp has excellent flexural modulus and overall performance is better than waste paper.The optimal interval of wet paper embryo moisture content,hot pressing temperature and hot pressing pressure during the molding process was determined by single factor experiment.The optimization experiment was carried out by the response surface method to obtain the optimal process parameters.When the hot pressing temperature is 175?,the hot pressing pressure is 6.9 MPa,the wet paper embryo water content is 70%,and its performance index:the crack length is 7697.93m,and the bending strength is 72.36 MPa,which are close to the predicted value.The influence of various factors in the molding process on the properties of the molding material is as follows:wet paper embryo moisture content>hot pressing pressure>hot pressing temperature.On the basis of the previous optimization experiment,the shower control valve was used as a packaging product to simulate the drop test of the pulp molded packaging liner prepared from straw pulp and waste paper pulp.The results show that the deformation resistance of straw molded liner is better than that of waste paper pulp,and the straw molding material has a certain resilience and can absorb energy well,which is in line with the characteristics of high-strength pulp molding packaging materials.The simulation results of ANSYS software are basically consistent with the actual drop situation,which provides experimental and theoretical basis for the application of computer simulation software in the field of pulp molding.