Evaluation of lightweight fiberboard using recycled polystyrene as a part of binder

Document Type : Research Paper

Authors

1 Wood and Paper Science and Technology, Faculty of Natural Resources, Tarbiat Modares University

2 Tarbiat Modares University

Abstract

Background and objectives: Nowadays, production of lightweight fiberboard with density lower than 500 kg/m3 gained a lot of interests for both non-structural and insulation applications in buildings. Environmental friendliness, lower price, recyclability, superior thermal and sound insulation, and desirable mechanical properties are some of the advantages of lightweight fiberboard compared to those of polymeric (polystyrene and polyurethane foams) and mineral-based (glass and mineral wool) insulation boards. Replacement of isocyanate and improving the board flexibility are in major focus for such panel’s producers. Hence, the aim of this study was to evaluate the production capability of lightweight fiberboard by replacing the isocyanate with polystyrene resin obtained from foam dissolution in methylene chloride solution. To this end, the effect of press temperature, solvent to foam weight ratio, different percentages of isocyanate replacement with polystyrene adhesive and board density on the physical and mechanical properties of lightweight fiberboard were investigated.

Materials and methods: Lightweight fiberboard (10 mm thick) with density from 200 – 300 kg/m3 were produced using wood fiber with combination of isocyanate and polystyrene as adhesive. In this study, mechanical (bending strength, modulus of elasticity, compression strength and tensile strength perpendicular to panel surface (internal bond)) and physical properties (thickness swelling and water absorption) of the panels were evaluated.

Results: The best modulus of elasticity, tensile and compressive strength was observed in boards made at 160°C. Increasing the weight ratio of solvent (methylene chloride) to polystyrene foam had a negative effect on these properties. Also, changing the solvent to foam ratio did not have a significant effect on the physical properties (thickness swelling and water absorption) of lightweight fiberboard. Increasing the percentages of isocyanate replaced with polystyrene adhesive (from 15 to 45% (based on the amount of isocyanate used)) improved the bending and physical properties and weakened the compressive and tensile strengths perpendicular to the panel’s surface. Mechanical properties (bending strength, modulus of elasticity, compressive and tensile strength) of the lightweight fiberboard as well as the swelling thickness of samples have increased significantly with increasing the board’s density.

Conclusion: In this study, lightweight fiberboard was developed using isocyanate as an expensive and toxic adhesive replaced with adhesive made from recycled polystyrene foams. The results showed good performance of boards made with 45% isocyanate replaced with polystyrene adhesive. Generally speaking, a promising alternative for recycling of polystyrene foams (used as adhesives for wood-based panels industries) was presented in this research while lightweight fiberboard was also produced as non-structural and insulating applications having less isocyanate consumption.

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 1.Abdulkareem, S.A., and Adeniyi, A.G. 2017. Production of particle boards using polystyrene and bamboo wastes. Nigerian J. of Technology. 36: 3. 788-793.
2.Abdulkareem, S.A., and Adeniyi, A.G. 2017. Development of particleboard from waste styrofoam and sawdust. Nigerian J. of Technological Development. 14: 1. 18-22.
3.Bekhta, P., and Sedliačik, J. 2019. Environmentally-friendly high-density polyethylene-bonded plywood panels. Polymers. 11: 7. 1166.
4.Chantawansri, T.L., Sirk, T.W., Mrozek, R., Lenhart, J.L., Kroger, M., and Sliozberg, Y.L. 2014. The effect of polymer chain length on the mechanical properties of triblock copolymer gels. Chemical Physics Letters. 612: 157-161.
5.Qin, R., Ren, X., Fifield, L.S., Simmons, K.L., and Li, K. 2011. Hemp-fiber-reinforced unsaturated polyester composites: Optimization of processing and improvement of interfacial adhesion. J. of Applied Polymer Science. 121: 2. 862-868.
6.Edalat, H.R., Amiri, A.N., Tabarsa, T., and Madhoushi, M. 2020. Investigation on the influence of raw material type on properties of ligno-cellulosic green insulation composite. J. of Wood and Forest Science and Technology.27: 3. 73-91.
7.FAO. 2021. Statistical yearbook. World food and agriculture. Food and agriculture organization of the United Nations. 365p.
8.Follrich, J., Müller, U., and Gindl, W. 2006. Effects of thermal modification on the adhesion between spruce wood (Picea Abies Karst.) and a thermoplastic polymer. Holz als Roh-und Werkstoff. 64: 5. 373-376.
9.Kawasaki, T., Zhang, M., and Kawai, S. 1998. Manufacture and properties of ultra-low-density fiberboard. J. of Wood Science. 44: 354-360.
10.Kazemi-Najafi, S. 2013. Use of recycled plastics in wood plastic composites - A review. Waste Management. 33: 9. 1898-1905.
11.Khakzad, J., Shalbafan, A., and Kazemi-Najafi, S. 2020. Lightweight tubular fiberboard: effect of hole diameters and number on panel properties. Maderas. Ciencia y Tecnologia. 22: 3. 311-324.
12.Kirsch, A., Ostendorf, K., and Euring, M. 2018. Improvement in the production of wood fiber insulation boards using hot-air hot-steam process. European J. of Wood and Wood Products.76: 1233-1240.
13.Lempfer, K. 2016. Insulation board production according to Siempelkamp’s dry-process: new process technology with great benefits for the environment. Siempelkamp Bulletin, pp. 14-19.
14.Masri, T., Ounis, H., Sedira, L.,Kaci, A., and Benchabane A. 2018. Characterization of new composite material based on date palm leaflets and expanded polystyrene wastes. Construction and Building Materials. 164: 410-418.
15.Niu, M., Wu, Z., Lin, X., Liu, Z., Xie, Y., Bhuiyan, I.U., and Wang, X. 2018. Manufacturing and properties of
ultra-low-density fiberboards with an unsaturated polyester resin by a dry process. European J. of Wood and Wood Products. 76: 3. 853-859.
16.Osemeahon, S.A., and Dimas, B.J. 2014. Development of urea formaldehyde and polystyrene waste as copolymer binder for emulsion paint formulation. J. of Toxicology and Environmental Health Sciences. 6: 3. 75-88.
17.Pizzi, A., and Mittal, K.L. 2018. Handbook of Adhesive Technology. 3rd Edition, Taylor and Francis Group, Marcel Dekker AG, Switzerland. 999p.
18.Shalbafan, A., Benthien, J.T., and Lerche, H. 2016. Biological characterization of panels manufactured from recycled particleboards using different adhesives. Bioresources. 11: 2. 4935-4946.
19.Thoemen, H., Irle, M., and Sernek, M. 2010. Wood-Based Panels: An Introduction for Specialists, Brunel University Press. 283p.