Slurry Rheological Properties And Buffering Characteristics Of Biomass Cushion Packaging Products

With the worsening of the environment in recent years, the industries of our country are affected in different degrees. Especially, the packaging industry is changing from polluting industries to the environmental protecting industry. So, environmental indicators are the important factors for the development of this industry. At home and abroad, the main green packaging materials include:paper pulp molding, corrugated cardboard, honeycomb cardboard, etc. However, owing to various problems in these green packaging materials, they still have a broad development space. Biodegraded cushion packaging materials become a research hotpot because of the advantages including the rich material sources, reproducible, good cushioning property, non-pollution in whole life cycle, etc.Biodegraded cushion packaging materials contain plant fiber, starch and other auxiliary as the main raw materials, and they are in one-step compression foam molding. But in mass production, the plastic viscosity and yield force of the materials restrict the automatic feeding. The starch aging retro gradation and fiber dividing fibrillation also have a direct influence on the forming and cushioning properties. Scholars at home and abroad have little research on the pretreatment and rheological properties of the raw material. So, in this test, the rheological properties of the raw material and the starch pretreatment are the research points, mainly including:(1) observing and analyzing the structure of starch in biodegraded cushion packaging materials by SEM, and understanding its structure characteristics and chemical properties; according to the characteristics of the corresponding plasticizing effect, analyzing the crystallinity of starch by XRD, after the plasticization; analyzing the hydroxyl of thermoplastic starch by FTIR, then determining the plasticizing starch process, parameters and the matching relationship.(2) studying the rheological properties of paste of biodegraded cushion packaging materials. The data analysis shows that the slurry is non-newtonian fluid with the property of shear thinning, and the systematic apparent viscosity declines along with the shear rate increasing and tends to be stable finally. Via analysis, Carson model can fit confluence variable test data better. With temperature rising, the plastic viscosity and yield strength of paste become smaller, and the slurry rheological property is sensitive to temperature.(3) Studying the composition distribution ratio of biodegraded cushion packaging materials and its influence on cushioning performance. Get the optimal distribution ratio by compression test, tensile test and the spring back test. Compared with EPE and EPS, the biodegraded cushion packaging materials have the advantages such as simple preparation process and full degradability, and its mechanical properties can basically meet the requirements of the product packaging.In order to provide theoretical basis to analysis the molecular binding and optimize the pretreatment process and formula of the packaging material, provide basic data for the design of automatic feeding system in the industrialization production of this material, the starch pretreatment, the rheological properties of the slurry and the impact of main compositions on cushioning performance of the material are the research points in this paper.