| Moulded pulp is a new type degraded environmental package and it is widely used for cushion packaging. It is made out of paper-pulp which is injected to mould pattern after fixing. It owns good properties such as excellent cushioning and toughness, lightweight, degradation and good air penetrability etc. However, a lot of work should be done to improve its design, manufacture, and application, especially to optimize the structure design of moulded pulp at present.In this thesis, the mechanical properties of material of moulded pulp are mainly studied.And at different conditions the relationship of stress-strain is measured through experiment. It can be concluded that the relationship of stress-strain of paper-pulp is sensitive to density and rate of strain.The study puts forward the structure cushioning mechanism on the base of evaluating its material properties, structure and loads imposed to the moulded pulp and comes to the conclusion. The cushion course of moulded pulp is the process of these protrusions' buckling deformation and energy absorption.In addition to the testing on real world moulded pulp packaging samples, FEM modeling and analysis is carried out using the protrusions similar to those used in testing. Based on this numerical modeling, the study discusses the relationship between structure parameters and properties of moulded pulp and concludes that such parameters as the thickness, the length of side wall bearing load, the number and relative position of the protrusions etc influencing the characteristic of moulded pulp considerably.Some parameters characterizing the behavior of the protrusions have been advanced for the structure design to forejudge the properties of moulded pulp. The parameters are the load per unit length, the number of bearing point in unit area, uniformity of bearing point, and load per unit contact area.At last the strategy for optimisation of the geometry to improve the cushioning properties is provided.
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