Modification Of Polypropylene With ?-Nucleating Agent/LDH And Study On Crystallization Mechanism And Properties

In this paper,the intercalation of twelve alkyl sulfonic acid sodium acrylate intercalated into MgAl-CO3 Layered double hydroxides(LDH)by ultrasonic ion exchange method.The difference between the ultrasonic ion exchange method and the conventional ion exchange method are compared.The Modified Hydrotalcite(LDHs)and Modified Hydrotalcite and beta nucleating agent(?-LDHs)were mixed as filler with polypropylene(iPP).They was blended in the twin screw extruder to get two kinds of composite materials LDHs/PP and beta-LDHs/PP.The microstructure and macroscopical properties of different composites were further studied.Ultrasonic Modified Hydrotalcite(CLDH)was prepared by novel ultrasonic ion exchange reaction.Factors such as pH value,reaction temperature,reaction time,ultrasonic power and LDH were studied how to effect the ion exchanged reaction.The results of X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR)and scanning electron microscope(SEM)were found to be the best reaction conditions: pH=4,T=50 ?,t=1h,and ultrasonic power=70w.Compared with conventional ion exchange method,the LDH prepared by ultrasonic modification has higher intercalation rate and interlayer spacing.By studying the isothermal crystallization behavior of LDHs/PP composites,it is found that the three kinds of filler(LDH,DLDH,CLDH)can increase the crystallization rate of PP and play a good role in the nucleation of the heterogeneous nucleation.Among them,the crystallization rate of CLDH increased most significantly than that of PP.The isothermal crystallization behavior of ?-LDHs/PP composites shows that the combination of DLDH,CLDH and ? nucleating agent has a good hetero nucleation effect on PP crystallization,and the combination of CLDH and ? nucleating agent can improve the ability of inducing PP to produce ?-crystal.The study on the structure and properties of LDHs/PP composites shows that the intercalation-peeling degree of CLDH in the PP matrix is the highest,and the crystallization and mechanical properties of the corresponding composite CLDH/PP are the best.The study of the structure and properties of ?-LDHs/PP composite foundthat CLDH and ? nucleating agent have good dispersion in the PP matrix,and the intercalation-peeling degree is the highest,and the crystallization and mechanical properties of the corresponding composite ?-CLDH/PP are the best.