Abstract:

In order to make comprehensive utilization of agricultural waste banana stalk, the banana stalk fiber was extracted by chemical degumming process. On the basis of single factor test, the response surface method was used to establish quadratic regression equation with NaOH mass concentration, alkali cooking time and alkali cooking temperature as the influencing factors, and the tensile strength of banana stem fiber as the response value. The optimal combination was obtained by response surface analysis. The results showed that alkali cooking time had the greatest effect on the tensile strength of banana stem fiber, followed by NaOH mass concentration and finally the alkali cooking temperature. When the mass concentration of NaOH was 8.76 g/L, the alkali boiling time was 3.98 h, the alkali boiling temperature was 80.72℃, the ratio of solid to liquid was 1:20(g: mL), the degumming rate of banana stalk fiber was 82.4%, the cellulose was 67.69%, and the tensile strength was 433.93 MPa. Fourier transform infrared results showed that a large amount of hemicellulose and lignin were removed from banana stem fiber prepared by optimal conditions. Scanning electron microscopy showed that the fracture section of banana stem fiber showed a brittle-plastic composite fracture form.

Key words: banana pseudostem fiber, the response surface method, degumming rate, mechanical properties