Abstract
The article addresses the relevance of shear and uniaxial extensional flow behaviour on the crystallisation of isotactic polypropylenes differing in terms of molar mass distribution (MMD). The importance of combining several experimental techniques, namely rheological, thermal and microscopic, to follow the response of the material arising from the application of given processing conditions, is here demonstrated. Systems with a broader MMD possessing even residual amounts of high molar mass (M M) tails were shown to be more prone to develop β-phase crystallites. The latter effect was seen to be a consequence of the application of a step shear at a temperature for which the formation of β-phase is known to be preferential.
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References
Padden FJ, Keith HD. Spherulitic crystallisation in polypropylene. J Appl Phys. 1959;30:479–85.
Natta G, Corradini P. Structure and properties of isotactic polypropylene. Nuovo Cimmento Suppl. 1960;15:40–51.
Turner-Jones A, Aizlewood JM, Beckett DR. Crystalline forms of isotactic polypropylene. Makromol Chem. 1964;75:134–58.
Varga J. β-Modification of isotatic polypropylene: preparation, structure, processing, properties, and application. Macromol Sci Phys. 2002;41:1121–71.
Varga J. Crystallization melting and supermolecular structure of isotactic polypropylene. In: Karger-Kocsis J, editor. Polypropylene: structure, blends and composites, vol. 1. London: Chapman & Hall; 1995.
Kristiansen PM, Gress A, Smith P, Nanft D, Schmidt HW. Phase behavior, nucleation and optical properties of the binary system isotactic polypropylene/N, N′, N″-tris-isopentyl-1, 3, 5-benzene-tricarboxamide. Polymer. 2006;47:249–53.
Tjong SC, Shen JS, Li RKY. Morphological behaviour and instrumented dart impact properties of β-crystalline-phase polypropylene. Polymer. 1996;37:2309–16.
Karger-Kocsis J. How does phase transformation toughening work in semicrystalline polymers? Polym Eng Sci. 1996;36:203–10.
Kotek J, Raab M, Baldrian J, Grellmann W. The effect of specific β-nucleation on morphology and mechanical behavior of isotactic polypropylene. J Appl Polym Sci. 2002;85:1174–84.
Obadal M, Čermák R, Baran N, Stoklasa K, Šimoník J. Impact strength of β-nucleated polypropylene. Int Polym Process. 2004;19:35–9.
Gotsis AD, Zeevenhoven BLF. Effect of long branches on the rheology of polypropylene. J Rheol. 2004;48:895–914.
Sugimoto M, Masubuchi Y, Takimoto J, Koyama K. Melt rheology of polypropylene containing small amounts of high-molecular-weight chain. 2. Uniaxial and biaxial extensional flow. Macromolecules. 2001;34:6056–63.
Meerveld J, Peters GWM, Hütter M. Towards a rheological classification of flow induced crystallization experiments of polymer melts. Rheol Acta. 2004;44:119–34.
Balzano L, Rastogi S, Peters GWM. Flow induced crystallization in isotactic polypropylene-1, 3:2, 4-bis(3, 4-dimethylbenzylidene)sorbitol blends: implications on morphology of shear and phase separation. Macromolecules. 2008;41:399–408.
Nogales A, Hsiao BS, Somani RH, Srivinas S, Tsou AH, Balta-Calleja FJ, et al. Shear-induced crystallization of isotactic polypropylene with different molecular weight distributions: in situ small- and wide-angle X-ray scattering studies. Polymer. 2001;42:5247–56.
Baert J, Van Puyvelde P. Effect of molecular and processing parameters on the flow-induced crystallization of poly-1-butene. Part 1: kinetics and morphology. Polymer. 2006;47:5871–9.
Baert J, Van Puyvelde P, Langouche F. Flow-induced crystallization of PB-1: from the low shear rate region up to processing rates. Macromolecules. 2006;39:9215–22.
U.S. Patent 5,998,558.
Janeschitz-Kriegl H, Ratajski E, Wippel H. The physics of a thermal nuclei in polymer crystallization. Colloid Polym Sci. 1999;277:217–26.
Stadlbauer M, Eder G, Janeschitz-Kriegl H. Crystallization kinetics of two aliphatic polyketones. Polymer. 2001;42:3809–16.
Olley RH, Basset DC. On surface morphology and drawing of polypropylene films. J Macromol Sci Phys. 1994;33:209–27.
Hobbs SY, Pratt CF. The development of surface texture in blown polypropylene film. Polym Eng Sci. 1982;22:594–600.
Gahleitner M, Bachner C, Ratajski E, Rohaczeck G, Neißl W. Effects of the catalyst system on the crystallization of polypropylene. J Appl Polym Sci. 1999;73:2507–15.
Gahleitner M, Bernreitner K, Neißl W. Crystallisation and mechanical properties of polypropylene homopolymers as influenced by molecular structure and nucleation. Polym Test. 1995;14:173–87.
Stadlbauer M, Janeschitz-Kriegl H, Lipp M, Eder G, Ratjski E. New extensional rheometer for creep flow at high tensile stress. Part II. Flow induced nucleation for the crystallization of iPP. J Rheol. 2004;48:631–40.
Stadlbauer M, Janeschitz-Kriegl H, Lipp M, Eder G, Forstner R. Extensional rheometer for creep flow at high tensile stress. Part I. Description and validation. J Rheol. 2004;48:611–30.
Hadinata C, Boos D, Gabriel C, Wassner E, Rüllmann M, Kao N, et al. Elongation-induced crystallization of a high molecular weight isotactic polybutene-1 melt compared to shear-induced crystallization. J Rheol. 2007;51:195–216.
Yamaguchi M, Wagner MH. Impact of processing history on rheological properties for branched polypropylene. Polymer. 2006;47:3629–35.
Eckstein A, Suhm J, Friedrich C, Maier RD, Sassmannshausen J, Bochmann M, et al. Determination of plateau moduli and entanglement molecular weights of isotactic, syndiotactic, and atactic polypropylenes synthesized with metallocene catalysts. Macromolecules. 1998;31:1335–40.
Muenstedt H. Dependence of the elongational behavior of polystyrene melts on molecular weight and molecular weight distribution. J Rheol. 1980;24:847–68.
Takahashi T, Takimoto JH, Koyama K. Elongational viscosity for miscible and immiscible polymer blends. II. Blends with a small amount of UHMW polymer. J Appl Polym Sci. 1999;72:961–9.
Vleeshouwers S, Meijer HEH. A rheological study of shear induced crystallization. Rheol Acta. 1996;35:391–9.
Somani R, Hsiao BS, Nogales A, Fruitwala H, Srivinas S, Tsou AH. Structure development during shear flow induced crystallization of i-PP: in situ wide-angle X-ray diffraction study. Macromolecules. 2001;34:5902–9.
Varga J, Karger-Kocsis J. Rules of supermolecular structure formation in sheared isotactic polypropylene melts. J Polym Sci B Polym Phys. 1996;34:657–70.
Acknowledgements
The authors would like to thank E. Uttenthaler for the SAOS measurements, Christian Samhaber for the isothermal crystallisation measurements and to J. Wolfschwenger for the GPC data. Prof. G. Eder and Dr. E. Ratajski are greatly acknowledged for the nucleation density measurements. An acknowledgement is due to Dr. J. Reussner for his continuous support.
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Filipe, S., Knogler, B., Buchmann, K. et al. Shear and extensional flows as drivers for the crystallisation of isotactic polypropylene. J Therm Anal Calorim 98, 667–674 (2009). https://doi.org/10.1007/s10973-009-0517-2
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DOI: https://doi.org/10.1007/s10973-009-0517-2