Mechanical properties and crystallization behavior of three kinds of straws/nylon 6 composites.

After alkali treatment, wheat straw, maize straw and rice straw were mixed with a mixture of nylon 6 (PA6) and prepared into composites using the melt blending method. The mechanical properties and crystallization behavior of three kinds of straw fiber/PA6 composites were studied using tensile and impact tests, differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The results showed that increasing of the three kinds of straw fibers initially increased the tensile strength of the composites and then decreased, and that the tensile strength reached a maximum value when the wheat straw fiber content was 10%, which was 56.9% higher than that of the pure PA6. The impact strength of the composites initially decreased and then increased, with the maximum impact obtained for the composites with the wheat straw fiber content of 10%, which was 39.2% higher than that of the pure PA6. The introduction of the three kinds of straw fiber also induced the formation of α crystal formed in the PA6. With the increase of the straw fiber content, the grain size of the composite increased continuously, the crystallization temperature (Tc) decreased, the melting temperature (Tm) and crystalline changed slightly, and the maximum degree of crystallinity was obtained when the wheat straw fiber content was 10%.