Solid-State Synthesis of Aminated Starch at Room Temperature and Its Application in Polyurethane Synthetic Leather
摘要
To enhance the preparation method of starch derivatives and broaden the application field of starch, this paper presents the synthesis of aminated starch via a solid-state reaction at room temperature, utilizing alcohol amine and water-soluble starch as raw materials, along with sodium dodecyl sulfonate as a surfactant catalyst. The resulting aminated starches were characterized using Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, contact angle measurements, relative crystallinity assessments, and degree of substitution analyses. Additionally, the mechanical properties of polyurethane synthetic leather were investigated by adding the water-soluble starch and aminated starch as fillers. The results indicate that the amination reaction between starch and alcohol amine predominantly occurs at the interface where starch contacts alcohol amine. Notable findings include a relative increase in crystal plane spacing at 2θ = 22.6°, the reconstruction of hydrogen bonding on the starch surface, the emergence of a new characteristic absorption peak at 1530 cm−1 corresponding to the N–H bond, variations in degree of substitution, the changes in micro-morphology, ammonia content, and a decrease in the contact angle of water droplets on the aminated starches. These observations collectively demonstrate the successful preparation of aminated starches, which contribute to a partial improvement in the mechanical performance of polyurethane synthetic leather containing these modified starches.