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Effective in situ polyamide 6 microfibrils in isotactic polypropylene under microinjection molding: significant improvement of mechanical performance

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Abstract

Microparts of isotactic polypropylene (iPP)/polyamide 6 (PA6) blends were prepared with a particular injection molding method known as microinjection molding (MIM). Continuous and strong shear action exerted on the melts of iPP/PA6 directly promoted the formation of in situ PA6 microfibril in MIM. Moreover, hierarchical structures, namely, spherulite, cylindrites, and transcrystallization, were observed in the microparts. The synergetic effect of PA6 in situ microfibrils, β-nucleating agent (β-NA), and strong shear action even induced more oriented β-crystals around the surface of PA6 microfibrils in the core layer and markedly increased the β-crystal content. Results showed that adding PA6 and β-NA markedly raised the crystallization temperature of iPP, and the effect of PA6 microfibrils was evidently more pronounced than that of PA6 spherical particles in conventional blends which implies more nucleation sites on the microfibrils. Moreover, strong orientation of iPP molecular chain was also confirmed by 2D-WAXD. It is well worth mentioning that the mechanical property was remarkably improved by these special morphology and crystalline structures.

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References

  1. Giboz J, Copponnex T, Mélé P (2007) Microinjection molding of thermoplastic polymers: a review. J Micromech Microeng 17:96–109

    Article  Google Scholar 

  2. Giboz J, Copponnex T, Mélé P (2009) Microinjection molding of thermoplastic polymers: morphological comparison with conventional injection molding. J Micromech Microeng 19:25023–25034

    Article  Google Scholar 

  3. Attia UM, Marson S, Alcock JR (2009) Micro-injection moulding of polymer microfluidic devices. Microfluid Nanofluid 7:1–28

    Article  Google Scholar 

  4. Ding W, Chen Y, Liu Z, Yang S (2015) In situ nano-fibrillation of microinjection molded poly(lactic acid)/poly(ε-caprolactone) blends and comparison with conventional injection molding. RSC Adv 5:92905–92917

    Article  Google Scholar 

  5. Heckele M, Schomburg W (2003) Review on micro molding of thermoplastic polymers. J Micromech Microeng 14:1–14

    Article  Google Scholar 

  6. Michaeli W, Spennemann A, Gärtner R (2002) New plastification concepts for micro injection moulding. Microsyst Technol 8:55–57

    Article  Google Scholar 

  7. Zhao J, Mayes RH, Chen GE (2003) Effects of process parameters on the micro molding process. Polym Eng Sci 43:1542–1554

    Article  Google Scholar 

  8. Yang C, Yin XH, Cheng GM (2013) Microinjection molding of microsystem components: new aspects in improving performance. J Micromech Microeng 23:093001

    Article  Google Scholar 

  9. Giboz J, Spoelstra AB, Portale G (2011) On the origin of the “core-free” morphology in microinjection-molded HDPE. J Polym Sci Polym Phys 49:1470–1478

    Article  Google Scholar 

  10. Versavaud S, Regnier G, Gouadec G, Vincent M (2014) Influence of injection molding on the electrical properties of polyamide 12 filled with multi-walled carbon nanotubes. Polymer 55:6811–6818

    Article  Google Scholar 

  11. Liu F, Guo C, Wu X, Qian X, Liu H, Zhang J (2012) Morphological comparison of isotactic polypropylene parts prepared by micro-injection molding and conventional injection molding. Polym Adv Technol 23:686–694

    Article  Google Scholar 

  12. Chien RD, Jong WR, Chen SC (2005) Study on rheological behavior of polymer melt flowing through micro-channels considering the wall-slip effect. J Micromech Microeng 15:1389–1396

    Article  Google Scholar 

  13. Lu Z, Zhang K (2009) Crystal distribution and molecule orientation of micro injection molded polypropylene microstructured parts. Polym Eng Sci 49:1661–1665

    Article  Google Scholar 

  14. Pan Y, Shi S, Xu W, Zheng G, Dai K, Liu C (2014) Wide distribution of shish-kebab structure and tensile property of micro-injection-molded isotactic polypropylene microparts: a comparative study with injection-molded macroparts. J Mater Sci 49:1041–1048. doi:10.1007/s10853-013-7781-z

    Article  Google Scholar 

  15. Liou AC, Chen RH (2006) Injection molding of polymer micro-and sub-micron structures with high-aspect ratios. Int J Adv Manuf Tech 28:1097–1103

    Article  Google Scholar 

  16. Michaeli W, Ziegmann C (2003) Micro assembly injection moulding for the generation of hybrid microstructures. Microsyst Technol 9:427–430

    Article  Google Scholar 

  17. Lotz B, Wittmann J, Lovinger A (1996) Structure and morphology of poly (propylenes): a molecular analysis. Polymer 37:4979–4992

    Article  Google Scholar 

  18. Varga J (2002) β-Modification of isotactic polypropylene: preparation, structure, processing, properties, and application. J Macromol Sci B 41:1121–1171

    Article  Google Scholar 

  19. Kotek J, Raab M, Baldrian J, Grellmann W (2002) The effect of specific β-nucleation on morphology and mechanical behavior of isotactic polypropylene. J Appl Polym Sci 85:1174–1184

    Article  Google Scholar 

  20. Naffakh M, Marco C, Ellis G (2012) Novel polypropylene/inorganic fullerene-like WS2 nanocomposites containing a β-nucleating agent: isothermal crystallization and melting behavior. J Phys Chem B 116:1788–1795

    Article  Google Scholar 

  21. Moitzi J, Skalicky P (1993) Shear-induced crystallization of isotactic polypropylene melts: isothermal WAXS experiments with synchrotron radiation. Polymer 34:3168–3172

    Article  Google Scholar 

  22. Somani RH, Hsiao BS, Nogales A, Fruitwala H, Srinivas S, Tsou AH (2001) Structure development during shear flow induced crystallization of i-PP: in situ wide-angle X-ray diffraction study. Macromolecules 34:5902–5909

    Article  Google Scholar 

  23. Menyhárd A, Varga J, Molnár G (2006) Comparison of different-nucleators for isotactic polypropylene, characterisation by DSC and temperature-modulated DSC (TMDSC) measurements. J Therm Anal Calorim 83:625–630

    Article  Google Scholar 

  24. Campoy I, Arribas J, Zaporta M, Marco C, Gomez MA (1995) Crystallization kinetics of polypropylene-polyamide compatibilized blends. Eur Polym J 31:475–480

    Article  Google Scholar 

  25. Varga J, Menyhárd A (2003) Crystallization, melting and structure of polypropylene/poly (vinylidene-fluoride) blends. J Therm Anal Calorim 73:735–743

    Article  Google Scholar 

  26. Menyhárd A, Varga J, Liber Á, Belina G (2005) Polymer blends based on the β-modification of polypropylene. Eur Polym J 41:669–677

    Article  Google Scholar 

  27. Shen J, Wang M, Li J, Guo S (2011) In situ fibrillation of polyamide 6 in isotactic polypropylene occurring in the laminating-multiplying die. Polym Adv Technol 22:237–245

    Article  Google Scholar 

  28. Yi X, Xu L, Wang Y, Zhong G, Ji X, Li Z (2010) Morphology and properties of isotactic polypropylene/poly (ethylene terephthalate) in situ microfibrillar reinforced blends: influence of viscosity ratio. Eur Polym J 46:719–730

    Article  Google Scholar 

  29. Chen YH, Huang ZY, Li ZM, Tang JH, Hsiao BS (2014) Simultaneous improvement of strength and toughness in fiber reinforced isotactic polypropylene composites by shear flow and a β-nucleating agent. RSC Adv 4:14766–14776

    Article  Google Scholar 

  30. Gahleitner M, Kretzschmar B, Pospiech D, Ingolic E, Reichelt N, Bernreitner K (2006) Morphology and mechanical properties of polypropylene/polyamide 6 nanocomposites prepared by a two-step melt-compounding process. J Appl Polym Sci 100:283–291

    Article  Google Scholar 

  31. Ohlsson B, Hassander H, Törnell B (1998) Effect of the mixing procedure on the morphology and properties of compatibilized polypropylene/polyamide blends. Polymer 39:4715–4721

    Article  Google Scholar 

  32. Yang Z, Zhang Z, Tao Y, Mai K (2008) Effects of polyamide 6 on the crystallization and melting behavior of β-nucleated polypropylene. Eur Polym J 44:3754–3763

    Article  Google Scholar 

  33. Jafari S, Gupta A, Rana S (2000) Effect of nylon 6 inclusions on the crystalline morphology of polypropylene–nylon 6 blends. J Appl Polym Sci 75:1769–1775

    Article  Google Scholar 

  34. Feng M, Gong F, Zhao C, Chen G, Zhang S, Yang M, Han CC (2004) The β-crystalline form of isotactic polypropylene in blends of isotactic polypropylene and polyamide-6/clay nanocomposites. J Polym Sci Pol phys 42:3428–3438

    Article  Google Scholar 

  35. Van der Beek MHE, Peters GW, Meijer HE (2006) Influence of shear flow on the specific volume and the crystalline morphology of isotactic polypropylene. Macromolecules 39:1805–1814

    Article  Google Scholar 

  36. Varga J, Ehrenstein GW (1996) Formation of β-modification of isotactic polypropylene in its late stage of crystallization. Polymer 37:5959–5963

    Article  Google Scholar 

  37. Lotz B (1998) α and β phases of isotactic polypropylene: a case of growth kineticsphase reentrency’in polymer crystallization. Polymer 39:4561–4567

    Article  Google Scholar 

  38. Zhang Y, Liu H, Zhang L, Zhang X, Zhang J (2013) Influence of β nucleation agent on the dispersion of nano-CaCO3 in isotactic polypropylene matrix. J Appl Polym Sci 128:3382–3389

    Article  Google Scholar 

  39. Huo H, Jiang S, An L, Feng J (2004) Influence of shear on crystallization behavior of the β phase in isotactic polypropylene with β-nucleating agent. Macromolecules 37:2478–2483

    Article  Google Scholar 

  40. Somani RH, Hsiao BS, Nogales A, Srinivas S, Tsou AH, Sics I, Balta-Calleja FJ, Ezquerra TA (2000) Structure development during shear flow-induced crystallization of iPP: in situ small-angle X-ray scattering study. Macromolecules 33:9385–9394

    Article  Google Scholar 

  41. Varga J, Karger-Kocsis J (1996) Rules of supermolecular structure formation in sheared isotactic polypropylene melts. J Polym Sci Polym Phys 34:657–670

    Article  Google Scholar 

  42. Varga J, Karger-Kocsis J (1995) Interfacial morphologies in carbon fibre-reinforced polypropylene microcomposites. Polymer 36:4877–4881

    Article  Google Scholar 

  43. Picken SJ, Aerts J, Visser R, Northolt MG (1990) Structure and rheology of aramid solutions: X-ray scattering measurements. Macromolecules 23:3849–3854

    Article  Google Scholar 

  44. Hsia CC (1959) Theory of mechanical breakdown and molecular orientation of a model linear high-polymer solid. J Appl Phys 30:1492–1497

    Article  Google Scholar 

Download references

Acknowledgements

This paper was financially supported by State Key Laboratory of Polymer Materials Engineering (Grant No. sklpme 2014-2-08), the National Science of China (51421061). The authors are also indebted to the Shanghai Synchrotron Radiation Facility (SSRF) in Shanghai, China for WAXD experiments.

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Authors and Affiliations

  1. College of Polymer Science and Engineering, The State Key Laboratory for Polymer Materials Engineering, Sichuan University, Chengdu, 610065, People’s Republic of China

    Liyan Yang, Juqiao Su, Qi Yang, Zhongguo Zhao, Yajiang Huang & Xia Liao

  2. Wuyuzhang Honors College, Sichuan University, Chengdu, 610065, People’s Republic of China

    Tongying Zhang

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  1. Liyan Yang
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  2. Juqiao Su
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Correspondence to Qi Yang.

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Yang, L., Su, J., Yang, Q. et al. Effective in situ polyamide 6 microfibrils in isotactic polypropylene under microinjection molding: significant improvement of mechanical performance. J Mater Sci 51, 10386–10399 (2016). https://doi.org/10.1007/s10853-016-0259-z

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