The aim of this work was to develop a mathematical model to investigate the rheological characteristics of viscoelastic pulp-fibre composite materials. The rheological properties of High-Yield Pulp (HYP) reinforced bio-based Nylon 11 (Polyamide 11) (PA11) composite (HYP/PA11) were investigated using a capillary rheometer. Novel predicted multiphase rheological-model-based polymer, fibre, and interphasial phases were developed. Rheological characteristics of the compo-site components influence the development of resultant microstructures; this in turn affects mechanical characteristics of a multiphase composite. The main rheological characteristics of polymer materials are viscosity and shear rate. Experimental and theoretical test results of HYP/PA11 show a steep decrease in apparent viscosity with increasing shear rate, and this melt-flow characteristic corresponds to shear-thinning behavior in HYP/PA11. The non-linear mathematical model to predict the rheological behavior of HYP/PA11 was validated experimentally at 200°C and 5000 S-1？shear rate. Finally, predicted and experimental viscosity results were compared and found to be in a strong agreement.
References
[1]
Pervaiz, M. and Sain, M. (2003) Carbon Storage Potential In natural Fibre Composites. Resources, Conservation and Recycling, 39, 325-340. http://dx.doi.org/10.1016/S0921-3449(02)00173-8
[2]
Bourmaud, A. and Baley, C. (2009) Rigidity Analysis of Polypropylene/Vegetal Fibre Composites after Recycling. Polymer Degradation and Stability, 39, 297-305. http://dx.doi.org/10.1016/j.polymdegradstab.2008.12.010
[3]
George, J., Sreekala, M.S. and Thomas, S. (2001) A Review on Interface Modification and Characterization of Natural Fiber Reinforced Plastic Composites. Polymer Engineering Science, 41, 1471-1485. http://dx.doi.org/10.1002/pen.10846
[4]
Gu, R. and Kokta, B. (2010) Mechanical Properties of PP Composites Reinforced with BCTMP Aspen Fiber. Journal of Thermoplastic Composite Materials, 23, 513-542. http://dx.doi.org/10.1177/0892705709355232
[5]
Bajpai, P. (2012) Brief Description of the Pulp and Paper Making Process. Biotechnology for Pulp and Paper Processing, 7-14.
[6]
Thomen, H. (2001) Modeling the Physical Processes in Natural Fiber Composites during Batch and Continuous Pressing. Oregon State University, Corvallis.
[7]
Plackett, D., Torgilsson, R. and Andersen, T. (2010) Influence of Fiber Type, Fiber Mat Orientation, and Process Time on the Properties of a Wood Fiber/Polymer Composite. International Journal of Polymeric Materials, 51, 1005-1018. http://dx.doi.org/10.1080/714975684
[8]
Uhlherr, P.H.T., Guo, J., Zhang, X.M., Zhou, J.Z.Q. and Tiu, C. (2005) The Shear-Induced Solid-Liquid Transition in Yield Stress Materials with Chemically Different Structures. Journal of Non-Newtonian Fluid Mechanics, 125, 101- 119. http://dx.doi.org/10.1016/j.jnnfm.2004.09.009
[9]
Liu, Y.J., Xu, N. and Luo, J.F. (2000) Modeling of Interphases in Fiber-Reinforced Composites under Transverse Loading Using Boundary Element Method. Journal of Applied Mechanics, 67, 41. http://dx.doi.org/10.1115/1.321150
[10]
Kaw, A. and Besterfield, G. (1998) Effect of Interphase on Mechanical Behavior of Composites. Journal of Engineering Mechanics, 117, 2641-2658. http://dx.doi.org/10.1061/(ASCE)0733-9399(1991)117:11(2641)
[11]
Yeh, J.R. (1992) The Effect of Interface on the Transverse Properties of Composites. International Journal of Solids and Structures, 29, 2493-2502. http://dx.doi.org/10.1016/0020-7683(92)90005-E
[12]
Gohil, P. and Shaikh, A. (2010) Analytical Investigation and Comparative Assessment of Interphase Influence on Elastic Behavior of Fiber Reinforced Composites. Journal of Reinforced Plastics and Composites, 29, 685-699.
[13]
Kari, S., Berger, H., Rodriguez, R.R. and Gabbert, U. (2005) Computational Evaluation of Effective Material Properties of Composites Reinforced by Randomly Distributed Spherical Particles. Composite Structures, 71, 397-400.
[14]
Lamnawar, K. and Maazouz, A. (2008) Rheology at the Interface and the Role of the Interphase in Reactive Functionalized Multilayer Polymers in Coextrusion Process. American Institute of Physics, 978, 7354-0549.
[15]
Larache, M., Agbossou, A., Pastor, J. and Muller, D. (1994) Role of Interphase on the Elastic Behavior of Composite Materials: Theoretical and Experimental Analysis. Journal of Composite Materials, 28, 1141-1157.
[16]
Deshpande, K. (2004) k-Version of Finite Element Method for Polymer Flows using Giesekus Constitutive Model. Ph.D. Thesis, University of Kansas, Lawrence.
[17]
Hosseinalipour, S., Tohidi, A. and Shokrpour, M. (2012) A Review of Dough Rheological Models Used in Numerical Applications. Journal of Computational and Applied Research in Mechanical Engineering, 1, 129-147.
[18]
Giesekus, H. (1982) A Simple Constitutive Equation for Polymer Fluids Based on the Concept of Deformation-Dependent Tensorial Mobility. Journal of Non-Newtonian Fluid Mechanics, 11, 69-109. http://dx.doi.org/10.1016/0377-0257(82)85016-7
