The Effect Of Halloysite Nanotubes On Structure And Properties Of The Polymer

The dispersibility of the nano-particles in the organic polymer materials and the interfacial bonding with the matrix are two particularly important factors in improving the comprehensive properties of the composites.It is difficult to make the nano-particles evenly dispersed in the composites,and it is great significance to explore the processing technology which is beneficial to improve the dispersibility of nano-materials in organic macromolecules.Halloysite nanobutes(HNTs)are mainly in the nanometer-sized tubular structure in the ore body,the chemical composition is similar as kaolinite,are natural silicate minerals.In this paper,HNTs were applied to polyamide-66(PA66)and polystyrene(PS)by pre-dispersion process.The surface modification of HNTs was carried out and applied to the preparation of PS/HNTs composites.The specific experimental content,depthly study of the preparation of composite materials,and their structure and performance,mainly in the following sections:(1)Unmodified HNTs were applied to PA66,and through direct blending method,solution pre-dispersion process and melt pre-dispersion process respectively,PA66/HNTs composites were prepared.The results show that the performance of the composites prepared by the pre-dispersion process is better,and the composite properties prepared by the solution pre-dispersion process is the best.Although,through the traditional processing technology HNTs can be more ideal dispersed in the matrix,through the pre-dispersion process,HNTs will have better dispersion.And HNTs and the matrix has a better adhesion.HNTs could significantly increase the crystallization temperature of HNTs and increase the crystallinity.(2)The unmodified HNTs were applied to PS,and PS/HNTs composites were prepared by solution pre-dispersion process and melt pre-dispersion process.The results show that there is no significant difference in the dispersion of HNTs in the final prepared PS/HNTs composites,although there are differences in the dispersion of HNTs in the masterbatch.The mechanical properties of the composites show that the PS/HNTs composites prepared by the solution pre-dispersion process have good comprehensive mechanical properties.The cross-sectional morphology of PS/HNTs composites and the difference of bonding behavior between HNTs and matrix was observed.The thermal properties of the material were analyzed by DSC and TGA.(3)The effect of HNTs(m-HNTs)modified by silane coupling agent on the structure and properties of PS/HNTs composites were studied.The surface modification of HNTs can improve the bonding state between HNTs and PS matrix.Compared with unmodified HNTs,PS/m-HNTs nanocomposites have higher mechanical properties.However,m-HNTs did not increase the impact strength of PS/m-HNTs composites.The m-HNTs have some effect on the heat resistance of PS/m-HNTs composites.