Accessible Requires Authentication Published by De Gruyter September 15, 2021

Fiber Length Distribution in Twin-Screw Extrusion of Fiber-Reinforced Polymer Composites: A Comparison between Shear and Extensional Mixing

M. Guo, X. Li and J. M. Maia

Abstract

New extensional mixing elements (EME) for twin-screw extrusion were applied to compound glass fibers (GF), carbon fibers (CF) or polyethylene terephthalate fibers (PETF) reinforced polymer composites with polymer matrix of polypropylene (PP) or polyethylene oxide (PEO) and the resulting fiber degradation upon processing was evaluated and compared with compounding via shear flow-dominated kneading blocks (KB). Composites structures were characterized in terms of fiber length and distribution, and cumulative length ratio, at five locations along the mixing zone. Although significant fiber breakage was achieved for both configurations, it was markedly lower in composites processed using the EME, because whereas the high shear stress kneading motion in the KB degrades fibers significantly, fiber breakup is significantly minimized by the alignment induced by the EME prior to flow in the high-stress regions.


João M. Maia, Department of Macromolecular Science and Engineering, Case Western Reserve University, Cleveland, OH 44106-7202, USA


Acknowledgements

The authors thank MiniFIBERS for kindly gifting the PETF. The authors would also like acknowledge Akash Agrawal for the help with the extrusion.

References

Bijsterbosch, H., Gaymans, R. J., "Polyamide 6-Long Glass Fiber Injection Moldings", Polym. Compos., 16, 363–369 (1995), DOI:10.1002/pc.750160504 Search in Google Scholar

Biolzi, L., Castellani, L. and Pitacco, I., "On the Mechanical Response of Short Fibre Reinforced Polymer Composites", J. Mater. Sci., 29, 2507–2512 (1995), DOI:10.1007/BF00363447 Search in Google Scholar

Carneiro, O. S., Caldeira, G. and Covas, J. A., "Flow Patterns in Twin-Screw Extruders", J. Mater. Process. Technol., 92–93, 309–315 (1999), DOI:10.1016/S0924-0136(99)00168-5 Search in Google Scholar

Carson, S. O., Covas, J. A. and Maia, J. M., "A New Extensional Mixing Element for Improved Dispersive Mixing in Twin-Screw Extrusion, Part 1: Design and Computational Validation", Adv. Polym. Technol., 36, 455–465 (2017), DOI:10.1002/adv.21627 Search in Google Scholar

Carson, S. O., Maia, J. M. and Covas, J. A., "A New Extensional Mixing Element for Improved Dispersive Mixing in Twin-Screw Extrusion, Part 2: Experimental Validation for Immiscible Polymer Blends", Adv. Polym. Technol., 37, 167–175 (2018), DOI:10.1002/adv.21653 Search in Google Scholar

Chen, H., Pandey, V., Carson, S. and Maia, J. M., "Enhanced Dispersive Mixing in Twin-Screw Extrusion via Extension-Dominated Static Mixing Elements of Varying Contraction Ratios", Int. Polym. Proc., 35, 37–49 (2020), DOI:10.3139/217.3857 Search in Google Scholar

Chin, W.-K., Liu, H.-T. and Lee, Y.-D., "Effects of Fiber Length and Orientation Distribution on the Elastic Modulus of Short Fiber Reinforced Thermoplastics", Polym. Compos., 9, 27–35 (1988), DOI:10.1002/pc.750090105 Search in Google Scholar

Cho, S., Hong, J. S., Lee, S. J., Ahn, K. H., Covas, J. A. and Maia, J. M., "Morphology and Rheology of Polypropylene/Polystyrene/Clay Nanocomposites in Batch and Continuous Melt Mixing Processes", Macromol. Mater. Eng., 296, 341–348 (2011), DOI:10.1002/mame.201000194 Search in Google Scholar

Covas, J. A., Nóbrega, J. M., and Maia, J. M., "Rheological Measurements along an Extruder with an On-Line Capillary Rheometer", Polym. Test., 19, 165–176 (2011), DOI:10.1016/S0142-9418(98)00086-5 Search in Google Scholar

Covas, J. A., Carneiro, O. S., Costa, P., Machado, A. V. and Maia, J. M., "Online Monitoring Techniques for Studying Evolution of Physical, Rheological and Chemical Effects along the Extruder", Plast. Rubber Compos., 33.1, 55–61 (2004), DOI:10.1179/146580104225018300 Search in Google Scholar

Covas, J. A., Carneiro, O. S., Maia, J. M., Filipe, S. A. and Machado, A. V., "Evolution of Chemistry, Morphology and Rheology of Various Polymer Systems along α Twin-Screw Extruder", Can. J. Chem. Eng., 80, 1065–1074 (2002), DOI:10.1002/cjce.5450800608 Search in Google Scholar

Covas, J. A., Maia, J. M., Machado, A. V. and Costa, P., "On-Line Rotational Rheometry for Extrusion and Compounding Operations", J. Non-Newtonian Fluid Mech., 148, 88–96 (2008), DOI:10.1016/J.JNNFM.2007.04.009 Search in Google Scholar

Curtis, P. T., Bader, M. G. and Bailey, J. E., "The Stiffness and Strength of α Polyamide Thermoplastic Reinforced with Glass and Carbon Fibres", J. Mater. Sci., 13, 377–390 (1978), DOI:10.1007/BF00647783 Search in Google Scholar

Denault, J., Vu-Khanh, T. and Foster, B., "Tensile Properties of Injection Molded Long Fiber Thermoplastic Composites", Polym. Compos., 10, 313–321 (1989), DOI:10.1002/pc.750100507 Search in Google Scholar

Doshi, S. R., Charrier, J.-M., "A Simple Illustration of Structure-Properties Relationships for Short Fiber-Reinforced Thermoplastics", Polym. Compos., 10, 28–38 (1989), DOI:10.1002/pc.750100105 Search in Google Scholar

Durin, A., De Micheli, P., Ville, J., Inceoglu, F., Valette, R. and Vergnes, B., "A Matricial Approach of Fibre Breakage in Twin-Screw Extrusion of Glass Fibres Reinforced Thermoplastics", Composites, Part A,, 48, 47–56 (2013), DOI:10.1016/J.COMPOSITESA.2012.12.011 Search in Google Scholar

Filipe, S., Cidade, M. T., Wilhelm, M. and Maia, J. M., "Evolution of the Morphological and Rheological Properties along the Extruder Length for Compatibilized Blends of α Commercial Liquid-Crystalline Polymer and Polypropylene", J. Appl. Polym. Sci., 99, 347–359 (2006), DOI:10.1002/app.22393 Search in Google Scholar

Filipe, S., Cidade, M. T., Wilhelm, M. and Maia, J. M., "Evolution of Morphological and Rheological Properties along the Extruder Length for Blends of α Commercial Liquid Crystalline Polymer and Polypropylene ", Polymer, (Guildf)., 45, 2367–2380 (2004), DOI:10.1016/J.POLYMER.2003.12.080 Search in Google Scholar

Fisa, B., "Mechanical Degradation of Glass Fibers during Compounding with Polypropylene\ Polym. Compos., 6, 232–241 (1985), DOI:10.1002/pc.750060408 Search in Google Scholar

Forgacs, O., Mason, S., "Particle Motions in Sheared Suspensions: IX. Spin and Deformation of Threadlike Particles", J. Colloid Sci., 14, 457–472 (1959), DOI:10.1016/0095-8522(59)90012-1 Search in Google Scholar

Fu, S.-Y., Lauke, B., "Effects of Fiber Length and Fiber Orientation Distributions on the Tensile Strength of Short-Fiber-Reinforced Polymers", Compos. Sci. Technol., 56, 1179–1190 (1996), DOI:10.1016/S0266-3538(96)00072-3 Search in Google Scholar

Fu, S.-Y., Lauke, B., Mäder, E., Yue, C.-Y. and Hu, X., "Tensile Properties of Short-Glass-Fiber- and Short-Carbon-Fiber-Reinforced Polypropylene Composites", Composites, Part A, 31, 1117–1125 (2000), DOI:10.1016/S1359-835X(00)00068-3 Search in Google Scholar

Guo, M., Chen, H. and Maia, J. M., "Effects of Structure and Processing on the Surface Roughness of Extruded Co-Continuous Poly(ethylene) Oxide/Ethylene-Vinyl Acetate Blends", J. Polym. Eng., 40, 763–770 (2019), DOI:10.1515/polyeng-2019-0238 Search in Google Scholar

Karacaer, Ö., Polat, T. N., Tezvergıl, A., Lassıla, L. V. and Vallıttu, P. K., "The Effect of Length and Concentration of Glass Fibers on the Mechanical Properties of an Injection- and α Compression-Molded Denture Base Polymer", J. Prosthet. Dent., 90, 385–393 (2003), DOI:10.1016/S0022-3913(03)00518-3 Search in Google Scholar

Kashfipour, M. A., Guo, M., Mu, L., Mehra, N., Cheng, Z., Olivio, J., Zhu, S., Maia, J. M. and Zhu, J., "Carbon Nanofiber Reinforced Co-Continuous HDPE/PMMA Composites: Exploring the Role of Viscosity Ratio on Filler Distribution and Electrical/Thermal Properties", Compos. Sci. Technol., 184, 107859 (2019), DOI:10.1016/J.COMPSCITECH.2019.107859 Search in Google Scholar

Ock, H. G., Kim, D. H., Ahn, K. H., Lee, S. J. and Maia, J. M., "Effect of Organoclay as α Compatibilizer in Poly(lactic acid) and Natural Rubber Blends", Eur. Polym. J., 76, 216–227 (2016), DOI:10.1016/J.EURPOLYMJ.2016.01.042 Search in Google Scholar

Rauwendaal, C., "Dispersive Mixing Capability", Spec. Molding Tech. Appl. Des. Mater. Process., 307, 638–641 (2002), DOI:10.1016/B978-188420791-4.50040-7 Search in Google Scholar

Sasayama, T., Inagaki, M. and Sato, N., "Direct Simulation of Glass Fiber Breakage in Simple Shear Flow Considering Fiber-Fiber Interaction", Composites, Part A, 124, 105514 (2019), 10.1016/j.compositesa.2019.105514 Search in Google Scholar

Thomason, J. L., Vlug, M. A., Schipper, G. and Krikor, H. G. L. T., "Influence of fibre Length and Concentration on the Properties of Glass Fibre-Reinforced Polypropylene: Part 3• Strength and Strain at Failure", Composites, Part A, 27, 1075–1084 (1996), DOI:10.1016/1359-835X(96)00066-° Search in Google Scholar

Unterweger, C., Brüggemann, O. and Fürst, C., "Effects of Different Fibers on the Properties of Short-Fiber-Reinforced Polypropylene Composites", Compos. Sci. Technol., 103, 49–55 (2014), 10.1016/j.compscitech.2014.08.014 Search in Google Scholar

von Turkovich, R., Erwin, L., "Fiber Fracture in Reinforced Thermoplastic Processing", Polym. Eng. Sci., 23, 743–749 (1983), DOI:10.1002/pen.760231309 Search in Google Scholar

Zhang, F., Guo, M., Xu, K., He, G., Wu, H. and Guo, S., "Multilayered Damping Composites with Damping Layer/Constraining Layer Prepared by α Novel Method", Compos. Sci. Technol., 101, 167–172 (2014), DOI:10.1016/J.COMPSCITECH.2014.06.021 Search in Google Scholar

Zhang, L., Tian, X., Malakooti, M. H. and Sodano, H. A., "Novel Self-Healing CFRP Composites with High Glass Transition Temperatures", Compos. Sci. Technol., 168, 96–103 (2018), DOI:10.1016/J.COMPSCITECH.2018.09.008 Search in Google Scholar

Received: 2020-04-22
Accepted: 2020-06-14
Published Online: 2021-09-15
Published in Print: 2021-09-27

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