| The chemical composition of basic magnesium chloride(BMC) whisker is Mgx(OH)y Clz·mH2O(2x-y-z=0,0≤m≤6), and its morphology is needle or fiber. Due to the characteristics of high fire behavior, low thermal conductivity, excellent wear-resisting and mechanical properties, BMC is widely use in areas of plastics, rubbers and resins as filling agents and heat stabilizer. With the development of material science, more and more researches were studied to settle the problem between increasing requirements of people and short points of meterials. However, BMC can inhance plastics'thermal stability and mechanical properties unless its compatibility and whisker structure well preserved.This study was aimed to settle the utilization problem of BMC's applications and cost in Plastic. Firstly, one-dimensional BMC was controlled prepared in two different system. Then, BMC was pretreated by silane coupling agent 3-(trimethoxysilyl) propyl methacrylate (y-MPS) and then conducted to surface radical grafting polymerization, the grafted BMC was applied to poly(vinyl chloride)(PVC) and ABS/PP composites respectively at last. The effects of MgCl2 concentration, molar ratio (R), and hydrothermal conditions on the structure and morphology of BMC were investigated, Besides, the influence of reaction conditions on both conservation of whisker topography and the effect of grafting polymerization is discussed, both thermal stability of PVC and mechanical properties of ABS/PP composites were studied in this paper. The main contents and results were as follows:It is found that, both in two systems of CaO-MgCl2-H2O and CaO/MgO-MgCl2-H2O, BMC can only be synthesized when the MgCl2 concentration was greater than 3 mol/L The molar ratio R plays a key role to the structure and morphology of BMC. The diameter and radius-length ratio of BMC increase with the MgCl2 concentration and R. In the system of CaO-MgCl2-H2O, the optimum conditions to prepare BMC are [MgCl2]=4 mol/L and R=0.05. The reaction temperature determines the phases of BMC, where phase 3 (Mg2(OH)3Cl·4H2O) is stable at below 150℃and phase 9 (Mg10(OH)18Cl2·5H2O) is obtained at above 150℃. The optimum R to prepare BMC is between 0.025 and 0.075 in the system of CaO/MgO-MgCl2-H2O, using calcined dolomite.The result of grafting study shows that the reaction condition has a strong impact on the topography of nano-composite material. The grafting efficiency is maximum (up to 56.1%) and the appearance of BMC whisker is well conserved when ethanol:water=8:2,the reaction temperature is 82℃,and the reaction time is 6 hours.When applied to PVC composites, g-BMC can enhance the thermal stability and increase the decomposition temperature of PVC. When 2.5 wt% g-BMCwas added, the color change time and Congo red time of PVC composites are 140 min and 204 min.The test results of composites'mechanical property and melt performance indicated that as the g-BMC packing content increased when in experimental range, the composites tensile strength improved as well; When the content of master batch was 15% and the g-BMC packing content was about 55%, the composites had better impact property; when the content of PP is 9% to 10%, the composites has the best tensile strength and impact property; while the g-BMC packing content has little effect on the tensile strength, it has improved impact property greatly with its increased use; with respect to melt performance, it reached the maximum when the content of PP is about 10%, while it decreased with the increase of g-BMC packing content.
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