Liu X, Dai K, Hao X, Zheng G, Liu C, Schubert DW, Shen C (2013)
Publication Language: English
Publication Status: Published
Publication Type: Journal article, Original article
Publication year: 2013
Book Volume: 52
Pages Range: 11996-12002
Journal Issue: 34
URI: https://pubs.acs.org/doi/10.1021/ie401162c
DOI: 10.1021/ie401162c
Although both shear flow and β-nucleating agent (β-NA) could separately induce β-crystal in isotactic polypropylene (iPP), their combination, particularly in the typical industrial processes, in fact has received comparatively little attention. In the current study, two-dimensional wide-angle X-ray diffraction and small-angle X-ray scattering (2D-WAXD/SAXS) measurements were performed to investigate the effect of β-NA on the crystalline structure of the oriented shear zone in injection molded iPP. It is observed that, regardless of the β-NA concentration, parent–daughter structure of α-crystal can be formed in iPP. Furthermore, the fraction of daughter lamellae elevates with the increasing concentration of β-NA. Interestingly, unexpected scattering patterns of (300) reflection for β-crystal, which is similar with that for parent–daughter lamellar branching of α-crystal, is exclusively found in iPP with higher concentration of β-NA (1.0 wt %). The most possible explanation is that the addition of high content of β-NA lowers the free energy barrier. Additionally, the same change tendency of long period, crystal lamellar thickness and lateral dimension, d-spacing and crystallite size is found, viz., they first increase and then decrease with the increasing β-NA content. The results demonstrate that the concentrations of β-NA have a significant effect on the crystal grain structure under the practical molding process.
APA:
Liu, X., Dai, K., Hao, X., Zheng, G., Liu, C., Schubert, D.W., & Shen, C. (2013). Crystalline structure of injection molded β-isotactic polypropylene: Analysis of the oriented shear zone. Industrial & Engineering Chemistry Research, 52(34), 11996-12002. https://doi.org/10.1021/ie401162c
MLA:
Liu, Xianhu, et al. "Crystalline structure of injection molded β-isotactic polypropylene: Analysis of the oriented shear zone." Industrial & Engineering Chemistry Research 52.34 (2013): 11996-12002.
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