Preparation And Complex Retardant Polypropylene Modified Pentaerythritol And Ammonium Polyphosphate Microcapsules

In this paper, we studied the effects of modified ammonium polyphosphate (MAPP) and microcapsule pentaerythritol (CPER) complex flame retardant on the properties of polypropylene (PP).Including the microcapsulation of pentaerythritol,modified process of MAPP,effectsof complex flame retardant on the flame retardant properties, mechanical properties and processability of PP.Silica gel (TEOS) and multiple phenyl methyl isocyanate (PAPI) was used to make microcapsules coated processing of pentaerythritol (PER),two microcapsules was synthesized: SPER and UPER. Fourier Transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) were used to analysesd the PER microcapsules results.Thermogravimetric analysis and water resistance test results showed that after microcapsules, the water-solubility of PER was significantly decreased, among which the water-solubility of PER dealed with PAPI reduce most, fell by about70%,at the temperature of28.Surface modification was carried out on the APP with dichloro dimethyl silane,the structure and thermal stability properties of APP were researched before and after the modification with the methord of FTIR and TG,contact angle measurement instrument was used to test the changes of APP contact angle. After surface modification, the thermal stability of APP was increased and contact angle was increase significantly,When the chlorosilane adding amount was2%, the reaction temperature was60℃, the modification effect is best.The properties of the composites were studied,using universal tensile machine, SEM, limiting oxygen index (LOI) and UL94-V0test,after the MAPP and CPER complex flame retardant was added toPP.When the IFR adding amount was30%, the MAPP/CPER was3:1, the flame retardant performance of composite is best,the flame retardant grade of each formula can achieve UL94-V0level. Among which the LOI value of MAPP/SPER is the highest, reached32,after treated with hot water the vertical flame test result can still achieved UL94-V0level. From the SEM photos of composite material after combustion,we can see that spline surface of the flame retardant system which used SPER as carbon agent was smooth and dense, however,the composite system used UPER as carbon agent had a large number of porosity on the surface.