Preparation of modified plasticized starch under pre/co-irradiation
Corn starch was modified by low-dose irradiation technology.The pre-irradiated and co-irradiated starch were mixed evenly respectively with caprolactam and propanetriol in proportion by the twin-screw extruder.The crystallinity,molecular structure and chemical bonds,thermodynamic properties,chemical composition,hydrophilicity and hydrophobicity of the extracted substances were characterized after low-temperature freeze crushing and Soxhlet extracting mixed starch.The results show that the thermal stability of starch reacted with caprolactam is improved with the same irradiation dose and different irradiation methods.Caprolactam is successfully grafted onto corn starch,resulting in the change of surface of starch crystal,the increase of nitrogen content on the surface and contact angle of samples.The contact angle of the co-irradiated graft reaches 99.229 °,whose hydrophobicity is greatly improved,and whose tensile strength reaches 8.3 MPa.
万方数据
维普
