Chunyan Wei

Research on sound absorption properties of multilayer structural material based on discarded polyester fiber

Thermoplastic polyurethane was reinforced with discarded polyester fiber to develop excellent mechanical properties of fiberboard composites, by hot pressing and mixing method. The fiberboard was drilled and made as a perforated plate, which was then coupled with polyester fabric; so a multiple layer structural material with good sound absorption function was achieved. Sound absorption properties were studied by changing holes diameter, air cavity depth, and perforation ratio. Theoretical absorption coefficient was obtained through building analytical model and massive theoretical calculation. It was found that it has good agreement with the experimental results. Hence, the analytical model could be adopted to predict the sound absorption coefficient of multilayer structural composites.

Effect of Micro-slit Plate Structure on the Sound Absorption Properties of Discarded Corn Cob Husk Fiber

Discarded degummed corn cob husk fiber was used as reinforced material and discarded thermoplastic polyurethane (TPU) particles were used as matrix material. The composites were fabricated by blended mastication-hot processing and the micro-slit plate having excellent absorption acoustic performance was fabricated by processing micro-slit on the composites. Sound absorption properties were studied by changing slit rate, slit width and air cavity depth. The results were choosing a smaller slit rate, a smaller slit width and a larger air cavity depth as possible to improve sound absorption coefficient in low frequency level. The double layer micro-slit plate based on corn cob husk fiber and TPU was designed to broaden sound absorption band and to have a wider application. Theoretical absorption coefficient was obtained through building analytical model and massive theoretical calculation. It was found that it had good agreement with the experimental results. Hence, the analytical model could be adopted to predict the sound absorption coefficient of the double layer micro-slit plate.

Study of coupling agent modification of cotton stalk bast fibres reinforced polylactic acid flame–retardant composites

In this experiment, cotton stalk bast fibre was modified, respectively, with A–171, KH–550 and TC–114 coupling agent, to improve the mechanical properties of fibre board. After testing the modified fibre board for its mechanical properties and analysing coupled fibre with FT–IR, it is proved that there were some new groups introduced into the fibre. Experimental results showed that adding A–171 and KH–550 type of silane coupling agent improves the mechanics properties of the material increasingly. A–171–type silane coupling agent was better for tensile strength and bending strength of the fibre board, increased by 31 and 65%, respectively, and the notched impact strength of fibre board KH–550 silane coupling agent was larger, and could be increased by 52.2%.