Increased nucleation efficiency of an in situ–formed β-nucleating agent for impact polypropylene copolymer
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In this study we generated zinc adipate (ZnAA) in situ [referred to herein as “ZnAA(IS)”] through the addition of its reaction precursors—adipic acid and zinc oxide—during the extrusion of impact polypropylene copolymer (IPC); we then investigated its nucleation performance as β nucleating agent using differential scanning calorimetry, polarized optical microscopy, wide-angle X-ray diffraction, and tests of mechanical properties. When compared with the pre-addition of ZnAA, the generation of ZnAA(IS) in situ resulted in higher nucleation effect toward the IPC, due to the smaller average particle size and more uniform dispersion of ZnAA(IS). In particular, compared with the neat IPC, the impact strength of the IPC prepared using 0.1 wt% of ZnAA(IS) increased by 103% at low temperature (−20 °C), whereas that of the IPC prepared with ZnAA increased by 38.9% under the same conditions. Moreover, when using Flash DSC to examine the crystallization behavior of the IPC under rapid cooling, we observed that, upon increasing the cooling rate, two crystalline peaks appeared for the neat and nucleated IPCs, presumably because of the crystallization of both the PP and PE homopolymers.
Keywordsβ-Nucleating agent Zinc adipate Crystallization Dispersion Polypropylene
This work was financially supported by the National Natural Science Foundation of China (Grants 21878089 and 21606084), National Key R&D Program of China (2016YFB0302201) and the Fundamental Research Funds for the Central Universities (22221818010).
- 8.Mani MR, Chellaswamy R, Marathe YN, Pillai VK (2016) New understanding on regulating the crystallization and morphology of the beta-polymorph of isotactic polypropylene based on carboxylate-Alumoxane nucleating agents. Macromolecules 49(6):2197–2205. https://doi.org/10.1021/acs.macromol.5b02466 CrossRefGoogle Scholar
- 18.Zhao S, Gong H, Yu X, Xin Z, Sun S, Zhou S, Shi Y (2016) A highly active and selective beta-nucleating agent for isotactic polypropylene and crystallization behavior of beta-nucleated isotactic polypropylene under rapid cooling. J Appl Polym Sci 133(32). https://doi.org/10.1002/app.43767
- 21.Yang Y, Xin Z, Zhao S, Shi Y, Zhou S, Zhou J, Ye C (2017) Nucleation effects of zinc adipate as β-nucleating agent in ethylene-propylene block copolymerized polypropylene. J Polym Res 24(9). https://doi.org/10.1007/s10965-017-1300-x
- 25.Yi X, Chen C, Zhong G-J, Xu L, Tang J-H, Ji X, Hsiao BS, Li Z-M (2011) Suppressing the skin–Core structure of injection-molded isotactic polypropylene via combination of an in situ Microfibrillar network and an interfacial Compatibilizer. J Phys Chem B 115(23):7497–7504. https://doi.org/10.1021/jp1118162 CrossRefPubMedGoogle Scholar