碱处理对马尼拉麻纤维结构及纸质振膜电声性能的影响.

The electro-acoustic (frequency response) characteristics of the loudspeaker usually be affected by the mechanical properties of the paper diaphragm. The mechanical properties of the diaphragm were improved by modifying the natural fiber. In this work, the structure of Manila hemp fiber and the mechanical properties, electro-acoustic performance of paper diaphragm were discussed on the effects of alkali concentration and treatment time. The surface morphology, crystal structure and chemical composition of Manila hemp fiber treated before and after were characterized by SEM, XRD, FT-IR, TGA. The results showed that the fiber surface roughness increased, and the crystallinity of the fiber increased and then decreased as the alkali concentration or the treatment time increased. The lignin and hemicellulose on the fiber surface were decreased. The thermo-stability of cellulose improved the same time lignin’s decreased. When the alkali concentration was too large or the treatment time was too long, the cellulose will be degraded, the mechanical strength of the diaphragm was affected. The fiber diaphragm has the best mechanical properties and electro-acoustic performance with 5 wt% of the alkali concentration, 3 h of the treatment time. [ABSTRACT FROM AUTHOR]