Effect of molecular weight distribution on the structure and properties of polypropylene cast film and stretched microporous membrane

Dahua Chen; Liangdong Yin; Zhixiang Su; Jiayi Xie; Ruijie Xu; Caihong Lei

doi:10.1515/polyeng-2023-0118

Abstract

Two isotactic polypropylene (iPP) resins with approximate weight-average molecular weight (Mw) and different molecular weight distribution (MWD) were chosen to prepare cast films by the melt-stretching method. The lamellar morphology and mechanical properties of the initial precursor films and stretched microporous membranes were characterized. It was found that PP1 resin with a broader MWD exhibits a higher relaxation time of around 5.5 s, a larger entanglement density of 24.7 mol/m³ and fast crystalline ability. The lamellar lateral size, orientation degree and entanglement density of the corresponding cast film are significantly increasing, resulting in higher elastic recovery and more apparent strain-hardening behavior. The PP resin with broader MWD also benefits the pore formation, resulting in a larger pore size and better air permeability of the stretched microporous membrane.

Keywords: crystallization; polypropylene; molecular weight distribution

Corresponding authors: Jiayi Xie, School of Chemistry and Civil Engineering, Shaoguan University, Shaoguan 512005, P. R. China, E-mail: xiejy710@163.com; and Caihong Lei, Guangdong Provincial Key Laboratory of Functional Soft Condensed Matter, School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006, P. R. China, E-mail: lch528@gdut.edu.cn

Funding source: The Youth Fund Project of Regional Joint Foundation- Fundamental and Applied Basic Research Foundation of Guangdong Province

Award Identifier / Grant number: 2021A1515110648

Funding source: Guangzhou Municipal Science and Technology Project

Award Identifier / Grant number: 202102020952

Funding source: Foshan Science and Technology Innovation Project

Award Identifier / Grant number: FS0AA-KJ919-4402-0145

Funding source: Project of Science Foundation of Guangdong Province

Award Identifier / Grant number: 2021A1515011914

Funding source: National Natural Science Foundation of China

Award Identifier / Grant number: 52173033

Research ethics: Not applicable.
Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
Competing interests: The authors declare no conflicts of interest regarding this article.
Research funding: The authors would like to thank the Project of the National Science Foundation of China under grant 52173033, Guangzhou Science and Technology Plan Project (202102020952), Project of Science Foundation of Guangdong Province (2021A1515011914), The Youth Fund Project of Regional Joint Foundation- Fundamental and Applied Basic Research Foundation of Guangdong Province (2021A1515110648), Foshan Science and Technology Innovation Project (no. FS0AA-KJ919-4402-0145).

References

1. Mchugh, A. The role of polymer membrane formation in sustained release drug delivery systems. J. Control Release 2005, 109, 211–221. https://doi.org/10.1016/j.jconrel.2005.09.038.Search in Google Scholar PubMed

2. Lee, S.-Y., Park, S.-Y., Song, H.-S. Lamellar crystalline structure of hard elastic HDPE films and its influence on microporous membrane formation. Polymer 2006, 47, 3540–3547. https://doi.org/10.1016/j.polymer.2006.03.070.Search in Google Scholar

3. Sadeghi, F., Tabatabaei, S. H., Ajji, A., Carreau, P. J. Effect of PVDF characteristics on extruded film morphology and porous membranes feasibility by stretching. J. Polym. Sci. Pol. Phys. 2010, 47, 1219–1229. https://doi.org/10.1002/polb.21725.Search in Google Scholar

4. Wang, J., Xu, Z., Xu, Y. Preparation of poly(4-methyl-1-pentene) asymmetric or microporous hollow-fiber membranes by melt-spun and cold-stretch method. J. Appl. Polym. Sci. 2006, 100, 2131–2141. https://doi.org/10.1002/app.235975.Search in Google Scholar

5. Sadeghi, F., Ajji, A., Carreau, P. J. Analysis of microporous membranes obtained from polypropylene films by stretching. J. Membrane Sci. 2007, 292, 62–71. https://doi.org/10.1016/j.memsci.2007.01.023.Search in Google Scholar

6. Sadeghi, F., Ajji, A., Carreau, P. Study of polypropylene morphology obtained from blown and cast film processes: initial morphology requirements for making porous membrane by stretching. J. Plast. Film. Sheet. 2005, 21, 199–216. https://doi.org/10.1177/8756087905057085.Search in Google Scholar

7. Tabatabaei, S. H., Carreau, P. J., Ajji, A. Microporous membranes obtained from PP/HDPE multilayer films by stretching. J. Membrane Sci. 2009, 345, 148–159. https://doi.org/10.1016/j.memsci.2009.08.038.Search in Google Scholar

8. Mileva, D., Gahleitner, M., Gloger, D., Tranchida, D. Crystal structure: a way to control properties in cast films of polypropylene. Polym. Bull. 2018, 75, 5587–5598. https://doi.org/10.1007/s00289-018-2343-9.Search in Google Scholar

9. Di Sacco, F., Gahleitner, M., Wang, J., Portale, G. Systematic investigation on the structure-property relationship in isotactic polypropylene films processed via cast film extrusion. Polymers 2020, 12, 1636. https://doi.org/10.3390/polym12081636.Search in Google Scholar PubMed PubMed Central

10. Sadeghi, F., Ajji, A., Carreau, P. J. Analysis of row nucleated lamellar morphology of polypropylene obtained from the cast film process: effect of melt rheology and process conditions. Polym. Eng. Sci. 2007, 47, 1170–1178. https://doi.org/10.1002/pen.20837.Search in Google Scholar

11. Yu, T.-H., Wilkes, G. L. Orientation determination and morphological study of high density polyethylene (HDPE) extruded tubular films: effect of processing variables and molecular weight distribution. Polymer 1996, 37, 4675–4687. https://doi.org/10.1016/S0032-3861(96)00307-2.Search in Google Scholar

12. Xu, G., Ding, L., Wu, T., Xiang, M., Yang, F. Effect of high molecular weight on pore formation and various properties of microporous membrane used for lithium-ion battery separator. J. Polym. Res. 2018, 25, 1–11. https://doi.org/10.1007/s10965-018-1567-6.Search in Google Scholar

13. Caihong, L., Shuqiu, W., Ruijie, X., Xinlong, P., Wenqiang, S., Bing, H. Influence of low molecular weight tail of polypropylene resin on the pore structure by room‐temperature stretching. Polym. Eng. Sci. 2013, 53, 2594–2602. https://doi.org/10.1002/pen.23527.Search in Google Scholar

14. Nogales, A., Hsiao, B. S., Somani, R. H., Srinivas, S., Tsou, A. H., Balta-Calleja, F. J., Ezquerra, T. A. Shear-induced crystallization of isotactic polypropylene with different molecular weight distributions: in situ small-and wide-angle X-ray scattering studies. Polymer 2001, 42, 5247–5256. https://doi.org/10.1016/S0032-3861(00)00919-8.Search in Google Scholar

15. Gray, A. P. Polymer crystallinity determinations by DSC. Thermochim. Acta 1970, 1, 563–579. https://doi.org/10.1016/0040-6031(70)80008-9.Search in Google Scholar

16. An, Y., Holt, J., Mitchell, G., Vaughan, A. Influence of molecular composition on the development of microstructure from sheared polyethylene melts: molecular and lamellar templating. Polymer 2006, 47, 5643–5656. https://doi.org/10.1016/j.polymer.2006.01.097.Search in Google Scholar

17. Gramespacher, H., Meissner, J. Interfacial tension between polymer melts measured by shear oscillations of their blends. J. Rheol. 1992, 36, 1127–1141. https://doi.org/10.1122/1.550304.Search in Google Scholar

18. Tschoegl, N. W. The Phenomenological Theory of Linear Viscoelastic Behavior: An Introduction; Springer: London, 2012.Search in Google Scholar

19. Kato, S., Tanaka, H., Yamanobe, T., Uehara, H. In situ analysis of melt-drawing behavior of ultrahigh molecular weight polyethylene films with different molecular weights: roles of entanglements on oriented crystallization. J. Phys. Chem. B 2015, 119, 5062–5070. https://doi.org/10.1021/jp512246d.Search in Google Scholar PubMed

20. Liu, C., He, J., Van Ruymbeke, E., Keunings, R., Bailly, C. Evaluation of different methods for the determination of the plateau modulus and the entanglement molecular weight. Polymer 2006, 47, 4461–4479. https://doi.org/10.1016/j.polymer.2006.04.054.Search in Google Scholar

21. Nobile, M. R., Cocchini, F. Evaluation of molecular weight distribution from dynamic moduli. Rheol. Acta 2001, 40, 111–119. https://doi.org/10.1007/s003970000141.Search in Google Scholar

22. Parrini, P., Corrieri, G. The influence of molecular weight distribution on the primary crystallization kinetics of isotactic polypropylene. Makromol. Chem. 1963, 62, 83–96. https://doi.org/10.1002/macp.1963.020620109.Search in Google Scholar

23. Xu, R., Chen, X., Xie, J., Cai, Q., Lei, C. Influence of melt-draw ratio on the crystalline structure and properties of polypropylene cast film and stretched microporous membrane. Ind. Eng. Chem. Res. 2015, 54, 2991–2999. https://doi.org/10.1021/acs.iecr.5b00215.Search in Google Scholar

24. Strobl, G., Schneider, M., Voigt-Martin, I. Model of partial crystallization and melting derived from small-angle X-ray scattering and electron microscopic studies on low-density polyethylene. J. Polym. Sci. Polym. Phys. Ed. 1980, 18, 1361–1381. https://doi.org/10.1002/pol.1980.180180615.Search in Google Scholar

25. Xu, M., Zhang, C., Zeng, Z., Pu, K. Semiconducting polymer nanoparticles as activatable nanomedicines for combinational phototherapy. ACS Appl. Polym. Mater. 2021, 3, 4375–4389. https://doi.org/10.1021/acsapm.1c00695.Search in Google Scholar

26. Xie, J., Xu, R., Chen, C., Chen, X., Zhang, F., Lei, C., Lin, Y., Li, L. Influence of material characteristics on the structure and properties of high-density polyethylene microporous membranes. RSC Adv. 2016, 6, 62769–62777. https://doi.org/10.1039/C6RA05133B.Search in Google Scholar

27. Somani, R. H., Hsiao, B. S., Nogales, A., Srinivas, S., Tsou, A. H., Sics, I., Balta-Calleja, F. J., Ezquerra, T. A. Structure development during shear flow-induced crystallization of i-PP: in-situ small-angle X-ray scattering study. Macromolecules 2000, 33, 9385–9394. https://doi.org/10.1021/ma001124z.Search in Google Scholar

28. Men, Y., Rieger, J., Strobl, G. Role of the entangled amorphous network in tensile deformation of semi-crystalline polymers. Phys. Rev. Lett. 2003, 91, 095502. https://doi.org/10.1103/PhysRevLett.91.095502.Search in Google Scholar PubMed

29. Haward, R. Strain hardening of thermoplastics. Macromolecules 1993, 26, 5860–5869. https://doi.org/10.1021/ma00074a006.Search in Google Scholar

30. Haward, R., Thackray, G. The use of a mathematical model to describe isothermal stress-strain curves in glassy thermoplastics. Proc. R. Soc. London, A 1968, 302, 453–472. https://doi.org/10.1098/rspa.1968.0029.Search in Google Scholar

Supplementary Material

This article contains supplementary material (https://doi.org/10.1515/polyeng-2023-0118).

Received: 2023-05-19

Accepted: 2023-08-27

Published Online: 2023-09-27

Published in Print: 2023-10-26

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Supplementary Material

Effect of molecular weight distribution on the structure and properties of polypropylene cast film and stretched microporous membrane

Abstract

References

Supplementary Material

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