Preparation And Modification Of Composite Foam Material Based On Citrus Pericarp Residue And Starch

In this study,the composite foam material was prepared by citrus pericarp residue mixing with corn starch though melt extrusion.Firstly,the ratio of raw material and process parameters were explored,and then the testing of response surface design was used to optimize extrusion parameters on the basis of material forming,screening out the formulation of material molding with better foaming effect and concern compression performance.Secondly,the composite foam material was nano-modified by addition of montmorillonite nanometer,to further improve the compression strength of citrus peel/starch-based composite foam materials.Finally,soil burial test was designed,simulating real environmental degradation,to analysis the degrade performance prepared by citrus peel/starch nano-composite foam materials.The main conclusions are as follows:1.the composite foam material with porus structure can be made by citrus peel mixing with corn starch though extrusion,and the addition of citrus peel had a certain influence on the structure and properties of the composite foam materials,its apparent density and compressive strength decreased with increasing levels of citrus peel,when the content of citrus peel reached 30%,the material had the maximum expansion radius,showing good foaming effect.2.Considering the effect of the foam state and compressive strength of the prepared material,the optimization parameters of citrus peel/starch-based composite foam material was obtained by software:bran 30%,glycerol 30%,and water 35%.Under this condition,the apparent density of the material was 0.942g/cm3,expansion was 287.82%,the compression strength was 210.58KPa.3.Addition of nano-montmorillonite had a greater impact on the performance of composite materials,nano with right amount added could not only enhance the compressive strength of the composite material,but also improved the foaming effect of citrus peel/starch composite material,of which 3%content nano materials had the greatest expansion and present a wealth of cell structure.However,material with too much nano would harm the composite extrusion,due to the reduced compatibility of composite material,5%and 7%nano-treated material presented darker appearance during the extrusion process,and their foaming and compressive strength were adversely affected.4.It was found the citrus peel/starch-based nano-composite foam material has very good performance of degradation when buried in the soil,and it degrade to the extent of 70%after burying in the soil three days.And the composite foam material improved pH values of soil in the degradation process,indicating that besides the excellent degradation performance the composite foam material had,it had the potential to increase soil fertility in the degradation process.In summary,the preparation of composite foam degradable material with citrus peel and starch is feasible,and the resulting material has good foaming effect.3%the modification of nano-montmorillonite on citrus peel/starch biodegradable composite foam material further improved the compression performance of materials and its expansion.In addition,the composite foam material has very good performance of degradation.Thus,citrus peel/starch biodegradable composite materials has great prospects on the replacing of traditional plastic foam packaging materials and the development of environment friendly material.