Preparation Of Zinc Pimelate And Nucleating Property As ?-Nucleating Agent For Isotactic Polypropylene

Polypropylene(PP)is one of the most common polyolefin resins at present.Though some mechanical properties of polypropylene can be comparable to some engineering plastics,it also has the weakness of low toughness,which limits its application in some certain areas where high toughness is required.Adding ? nucleating agent(?-NA)is an effective method to improve the toughness of polypropylene.It is simple and highly efficient and conducive to industrial production.Therefore,the production of low-cost and efficient polypropylene nucleating agent can effectively improve the competitiveness of the product.There are a few types of ?-NA with highly efficient and highly selective.Therefore,a new kind of high efficiency polypropylene ?nucleating agent zinc pimelate was prepared.Firstly,solution method was used to prepare zinc pimelate.The structure and morphology of the nucleating agent were studied by infrared spectroscopy,X-ray diffraction and scanning electron microscopy.The impact strength of the nucleatd polypropylene with an amount of 0.6 wt%Znpt(Solution)is 1.84 times higher than that of neat polypropylene.Differential scanning calorimetry(DSC),X-ray diffraction(WAXD),and polarized light microscopy(POM)results showed that Znpt(Solution)can effectively induce polypropylene to generate large amounts of(3 spherulites.Non-isothermal kinetics calculations showed that adding Znpt(Solution)changed the nucleation and crystallization method of polypropylene.Secondly,zinc pimelate was prepared by solid method and its nucleation effect on polypropylene was studied.The mechanical property results showed that after the adding of Znpt(Solid),the impact strength of PP rapidly increased and reached a stable value.The optimum addition amount was 0.1 wt%,and the impact strength increased from 37.1 J/m to 103.7 J/m;WXAD and DSC results showed that Znpt(Solid)can induce high content of ?-crystals and increase the crystallization temperature.POM results showed that compared with the addition of Znpt(Solution),the addition of Znpt(Solid)can significantly refine the spherulite size and accelerate the nucleation and crystallization process of PP.Non-isothermal kinetics calculations showed that adding Znpt(Solid)changed the nucleation and crystallization method of polypropylene.Finally,in order to optimize the solid synthesis process and study the synergy effect between pimelic acid(PA)and Znpt(Solid)or zinc oxide(ZnO)and Znpt(Solid),the influence of the molor ratio of raw materials on the nucleating property of polypropylene was investigated.The results showed that the optimal molor ratio of raw materials was 1:1(PA:ZnO).Under this ratio,mechanical properties of nucleated polypropylene and ?-crystal content all reached the maximum value.There was no synergy effect between the two raw materials and zinc pimate:When PA and Znpt(Solid)were added together,the nucleation effect of PA and Znpt(Solid)competed,and the nucleation effect of PA played a leading role which induced PP formed a crystal.When ZnO and Znpt(Solid)were added together,the weak ? nucleation effect of ZnO decreased the induction effect of Znpt(Solid)on PP.