摘要

In order to improve the mechanical strength of prototypes fabricated from wood-plastic composite powders by selective laser sintering(SLS) and to design the new composite powders formula applicable to SLS technology, two kinds of wood-plastic composite powders of cellulose/polyether sulfone(PES) and cellulose/polypropylene(PP) were prepared. The systems of cellulose/PES and cellulose/PP blends were blending computed by using the methods of molecular mechanics and molecular dynamics simulation methods. The binding energy distribution curves of cellulose with PES and PP were obtained respectively. By establishing molecular models of cellulose/PES blends with different mass ratios, the Flory-Huggins interaction parameter and static elastic mechanical properties of the models were calculated, and the effect of content of cellulose on the elastic properties of the blends was analyzed. Laser sintering experiments of cellulose/PES and cellulose/PP blends were carried out for verifying the simulation conclusions. The results show that compared with cellulose/PP composite powders, cellulose has the better compatibility with PES, which is suitable for SLS technology. With the addition of 20% to 25% mass fraction of cellulose, the compatibility of the material is at the best condition. The established blend model of cellulose/PES can be used to predict the elastic properties of the fabricated material.

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