Document Type : Research Paper


1 University of Technology, Baghdad, Iraq

2 Materials Engineering Department, University of Technology, Baghdad, Iraq

3 University of Technology, Baghdad, Iraq,


These works study the characterization of thermal and acoustic insulation behavior of Polymer Blend/Recycled Natural Fibers. Acoustic insulation is an important property in design criterion in buildings and used to avoid the damage caused by the sounds of the explosion of rockets and bombs. This work is done through reinforcing 80% epoxy resin EP with 20% polycarbonate PC with two different recycled natural fiber RNF (hemp fiber H.F., cornhusk fiber C.H.F) at various weight fractions of (2,4,6) %, the samples, were formed by hand lay-up then the acoustic and thermal insulation tests carried out. The results show that altering both kinds of RNF can improve acoustic insulation. Also, it could be noticed that sound insulation efficiency can improve with increasing RNF weight fraction. Finally, the optimum results got at 6% hemp composite that shows better acoustic insulation than cornhusk composites. The thermal conductivity improved by increasing the fiber weight fraction. The maximum value of thermal conductivity for composite samples with (H.F., C.H.F) fibers at (6% wt) equal to (0.71609W/m. Kº) and (0.73686W/m. Kº), respectively. The composite samples with C.H.F. fibers have slightly higher thermal conductivity value than composite samples with H.F.


[1] S. Ersoy and A. El-Hafid, “Investigation of sound properties of high density polyethylene / styrene butadiene rubber polymer composites”, Vibroengineering Procedia, Vol.1, pp.77–80, 2013.
[2] D. Chandramohan and K. Marimuthu, “A review on natural fibers", International Journal of Research and Reviews in Applied, Vol.8, No.2, pp.194–206, 2011.
[3] A. Olaitan, A. Terhemen, G. King, and O. Oluwatoyin, “Comparative assessment of mechanical properties of groundnut shell and rice husk reinforced epoxy composites”, Am. J. Mech. Eng., Vol.5, No.3, pp.76–86, 2017.
[4] W. D. Yang and Y. Li, “Sound absorption performance of natural fibers and their composites,” Science China Technological Sciences, Vol.55, No. 8, pp. 2278–2283, 2012.
[5] P. Sérgio, C. Fernando, F. Raul, R. Sohel, and P. Fernando, “Acoustical behavior of hybrid composite sandwich panels”, Key Engineering Materials, Vol.634, pp.455–464, 2015.
[6] H. P. Lee, B. Mun, P. Ng, and A. V. Rammohan, “An investigation of the sound absorption properties of flax / epoxy composites compared with glass / epoxy composites”, J. Nat. Fibers, Vol.14, No.1, pp.71–77, 2016.
[7] S. A. Hussain, V. Pandurangadu, and K. Palanikuamr, “Mechanical properties of green coconut fiber reinforced HDPE polymer composite,” Int. J. Eng. Sci. Technol., Vol.3, No.11, pp.7942–7952, 2011.
[8] S. A. Hussain, V. Pandurangadu, and K. Palanikuamr, “Mechanical properties of short bamboo fiber reinforced polyester composites filled with alumina particulate”, Eng. Sci. Technol. An Int. J., Vol.2, pp.449–453, 2012.
[9] W. M. Salih and E. M. Hadi, “Manufacturing of thermal and acoustic insulating from (white cement and hemp short fibers) by using recycled paper”, Engineering and Technology Journal, Vol.35, No.1, pp.173-182, 2017.
[10] N. Sombatsompop and A. K. Wood, “Measurement of thermal conductivity of polymers using an improved lee’s disc apparatus”, Polymer Test, Vol.16, No.3, pp.203–223, 1997.
[11] J. Zhang, Y. Shen, B. Jiang, and Y. Li, “Sound absorption characterization of natural materials and sandwich structure composites”, Aerospace, Vol.5, No.75, pp.1-13, 2018.
[12] H. Mamas, M. H. Fouladi, M. Al-atabi, and S. N. Namasivayam, “Acoustic absorption of natural fiber composites”, Journal of Engineering, Vol. 2016, pp.1-11, 2016,
[13] R. El-Sawalhi, J. Lux, and P. Salagnac, “Estimation of the thermal conductivity of hemp based insulation material from 3D tomographic images,” Heat Mass Transf., Vol.52, No.8, pp.1559–1569, 2016.