Abstract
Wood plastic composites (WPC) were made from polypropylene (PP), impact copolymer (ICP) and wood flour (WF) by varying the WF content from 10 to 40% with PP grafted maleic anhydride as a coupling agent. The effect of varying WF content was studied on rheological, thermal, mechanical properties and dynamic mechanical properties. Experimental small amplitude oscillatory shear (SAOS) data was compared with the Einstein–Batchelor and empirical Krieger–Dougherty relations. Significant dependence of mechanical and rheological properties on WF content was observed. Young’s modulus, flexural modulus and dynamic shear viscosity increased with WF content. Results of dynamic mechanical analysis (DMA) showed increase in storage modulus with WF content. Three millimeter thick compression molded composites sheets were thermoformed using axisymmetric molds with two draw depths. Sag observed visually during thermoforming decreased with increasing WF content. Components made from the composites showed close to uniform thickness distribution as compared to those from ICP.
-
Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
-
Research funding: None declared.
-
Conflict of interest statement: The authors declare no conflicts of interest regarding this article.
References
1. Barroso, V. C., Ribeiro, S. P., Maia, J. M. Unusual extensional behavior of a polystyrene/HIPS blend. Rheol. Acta 2003, 42, 483–490; https://doi.org/10.1007/s00397-003-0303-1.Search in Google Scholar
2. Lau, H. C., Bhattacharya, S. N., Field, G. J. Influence of rheological properties on the sagging of polypropylene and ABS sheet for thermoforming applications. Polym. Eng. Sci. 2000, 40, 1564–1570; https://doi.org/10.1002/pen.11286.Search in Google Scholar
3. Soury, E., Behravesh, A. H., Rizvi, G. M., Jam, N. J. Rheological investigation of wood-polypropylene composites in rotational plate rheometer. J. Polym. Environ. 2012, 20, 998–1006; https://doi.org/10.1007/s10924-012-0502-x.Search in Google Scholar
4. Twite–Kabamba, E., Mechraoui, A., Rodrigue, D. Rheological properties of polypropylene/hemp fiber composites. Polym. Compos. 2009, 30, 1401–1407.10.1002/pc.20704Search in Google Scholar
5. Gao, H., Song, Y. M., Wang, Q. W., Han, Z., Zhang, M. L. Rheological and mechanical properties of wood fiber-PP/PE blend composites. J. For. Res. 2008, 19, 315–318; https://doi.org/10.1007/s11676-008-0057-9.Search in Google Scholar
6. Maiti, S. N., Subbarao, R., Ibrahim, M. N. Effect of wood fibers on the rheological properties of i–PP/wood fiber composites. J. Appl. Polym. Sci. 2004, 91, 644–650; https://doi.org/10.1002/app.13157.Search in Google Scholar
7. Einstein, A. A new determination of molecular dimensions. Ann. Phys. 1906, 19, 289–306; https://doi.org/10.1002/andp.19063240204.Search in Google Scholar
8. Batchelor, G. K. The effect of Brownian motion on the bulk stress in a suspension of spherical particles. J. Fluid Mech. 1977, 83, 97–117; https://doi.org/10.1017/s0022112077001062.Search in Google Scholar
9. Mooney, M. The viscosity of a concentrated suspension of spherical particles. J. Colloid Sci. 1951, 6, 162–170; https://doi.org/10.1016/0095-8522(51)90036-0.Search in Google Scholar
10. Krieger, I. M., Dougherty, T. J. A mechanism for non–Newtonian flow in suspensions of rigid spheres. Trans. Soc. Rheol. 1959, 3, 137–152; https://doi.org/10.1122/1.548848.Search in Google Scholar
11. Stark, N. M., Rowlands, R. E. Effects of wood fiber characteristics on mechanical properties of wood/polypropylene composites. Wood Fiber Sci 2003, 35, 167–174.Search in Google Scholar
12. Karmarkar, A., Chauhan, S. S., Modak, J. M., Chanda, M. Mechanical properties of wood–fiber reinforced polypropylene composites: effect of a novel compatibilizer with isocyanate functional group. Compos. Appl. Sci. Manuf. 2007, 38, 227–233; https://doi.org/10.1016/j.compositesa.2006.05.005.Search in Google Scholar
13. Espert, A., Vilaplana, F., Karlsson, S. Comparison of water absorption in natural cellulosic fibres from wood and one-year crops in polypropylene composites and its influence on their mechanical properties. Compos. Appl. Sci. Manuf. 2004, 35, 1267–1276; https://doi.org/10.1016/j.compositesa.2004.04.004.Search in Google Scholar
14. Wu, J., Yu, D., Chan, C. M., Kim, J., Mai, Y. W. Effect of fiber pretreatment condition on the interfacial strength and mechanical properties of wood fiber/PP composites. J. Appl. Polym. Sci. 2000, 76, 1000–1010; https://doi.org/10.1002/(sici)1097-4628(20000516)76:7<1000::aid-app3>3.0.co;2-x.10.1002/(SICI)1097-4628(20000516)76:7<1000::AID-APP3>3.0.CO;2-XSearch in Google Scholar
15. Oksman, K., Clemons, C. Mechanical properties and morphology of impact modified polypropylene–wood flour composites. J. Appl. Polym. Sci. 1998, 67, 1503–1513.10.1002/(SICI)1097-4628(19980228)67:9<1503::AID-APP1>3.0.CO;2-HSearch in Google Scholar
16. Sain, M., Park, S. H., Suhara, F., Law, S. Flame retardant and mechanical properties of natural fibre–PP composites containing magnesium hydroxide. Polym. Degrad. Stabil. 2004, 83, 363–370; https://doi.org/10.1016/s0141-3910(03)00280-5.Search in Google Scholar
17. Stark, N. Influence of moisture absorption on mechanical properties of wood floor-polypropylene composites. J. Thermoplast. Compos. Mater. 2001, 14, 421–453; https://doi.org/10.1106/udky-0403-626e-1h4p.Search in Google Scholar
18. Bledzki, A. K., Faruk, O. Wood fibre reinforced polypropylene composites: effect of fibre geometry and coupling agent on physico-mechanical properties. Appl. Compos. Mater. 2003, 10, 365–444.10.1023/A:1025741100628Search in Google Scholar
19. Adhikary, K. B., Park, C. B., Islam, M. R., Rizvi, G. M. Effects of lubricant content on extrusion processing and mechanical properties of wood flour-high-density polyethylene composites. J. Thermoplast. Compos. Mater. 2011, 24, 155–226; https://doi.org/10.1177/0892705710388590.Search in Google Scholar
20. Rana, A. K., Mandal, A., Mitra, B. C., Jacobson, R., Rowell, R., Banerjee, A. N. Short jute fiber–reinforced polypropylene composites: effect of compatibilizer. J. Appl. Polym. Sci. 1998, 69, 329–367; https://doi.org/10.1002/(sici)1097-4628(19980711)69:2<329::aid-app14>3.0.co;2-r.10.1002/(SICI)1097-4628(19980711)69:2<329::AID-APP14>3.0.CO;2-RSearch in Google Scholar
21. Arbelaiz, A., Fernandez, B., Ramos, J. A., Retegi, A., Llano-Ponte, R., Mondragon, I. Mechanical properties of short flax fibre bundle/polypropylene composites: influence of matrix/fibre modification, fibre content, water uptake and recycling. Compos. Sci. Technol. 2005, 65, 1582–1674; https://doi.org/10.1016/j.compscitech.2005.01.008.Search in Google Scholar
22. Feng, D., Caulfield, D., Sanadi, A. R. Effect of compatibilizer on the structure–property relationships of kenaf–fiber/polypropylene composites. Polym. Compos. 2001, 22, 506–523; https://doi.org/10.1002/pc.10555.Search in Google Scholar
23. Hristov, V. N., Lach, R., Grellmann, W. Impact fracture behavior of modified polypropylene/wood fiber composites. Polym. Test. 2004, 23, 581–589; https://doi.org/10.1016/j.polymertesting.2003.10.011.Search in Google Scholar
24. Samal, S. K., Mohanty, S., Nayak, S. K. Polypropylene—bamboo/glass fiber hybrid composites: fabrication and analysis of mechanical, morphological, thermal, and dynamic mechanical behavior. J. Reinforc. Plast. Compos. 2009, 28, 2729–2747; https://doi.org/10.1177/0731684408093451.Search in Google Scholar
25. Santos, E. F., Mauler, R. S., Nachtigall, S. M. Effectiveness of maleated-and silanized-PP for coir fiber-filled composites. J. Reinforc. Plast. Compos. 2009, 28, 2119–2129; https://doi.org/10.1177/0731684408091704.Search in Google Scholar
26. Pracella, M., Chionna, D., Anguillesi, I., Kulinski, Z., Piorkowska, E. Functionalization, compatibilization and properties of polypropylene composites with hemp fibres. Compos. Sci. Technol. 2006, 66, 2218–2230; https://doi.org/10.1016/j.compscitech.2005.12.006.Search in Google Scholar
27. Ichazo, M. N., Albano, C., Gonzalez, J., Perera, R., Candal, A. M. Polypropylene/wood flour composites: treatments and properties. Compos. Struct. 2001, 54, 207–214; https://doi.org/10.1016/s0263-8223(01)00089-7.Search in Google Scholar
28. Qiu, W., Endo, T., Hirotsu, T. Structure and properties of composites of highly crystalline cellulose with polypropylene: effects of polypropylene molecular weight. Eur. Polym. J. 2006, 42, 1059–1068; https://doi.org/10.1016/j.eurpolymj.2005.11.012.Search in Google Scholar
29. Bhattacharyya, D., Martyn, B., Krishnan, J. Thermoforming wood fiber–polypropylene composite sheets. Compos. Sci. Technol. 2003, 63, 353–365; https://doi.org/10.1016/s0266-3538(02)00214-2.Search in Google Scholar
30. Vlachopoulos, J., Polychronopoulos, N. D. Rheology of Wood Plastic Composites Extrusion, Polymers. Tomas Bata University: Zlin, Czech Republic, 2018; pp. L-01-L-05.Search in Google Scholar
31. Lee, S. Y., Do, G. H., Gang, I. A. Thermal behavior of hwangto and wood flour reinforced high density polyethylene (HDPE) composites. J. Kor. Wood Sci. Technol. 2006, 34, 59–66.Search in Google Scholar
© 2021 Walter de Gruyter GmbH, Berlin/Boston
