Valorization of wool keratin in developing thermo-pressed plasticized films using factorial design

S. Touatou, N. Belhaneche-Bensemra


In this paper, wool keratin was investigated as feedstock for the production of protein-based plastics. Untreated wool fibers were thermo-pressed using glycerol as plasticizer at different levels (20 %, 30%, and 40%). Compression pressure, time and temperature were varied according to a 23 full factorial design. The mechanical properties were investigated by tensile measurements and discussed with respect to operating conditions. The thermal properties were studied by thermogravimetric analysis and differential scanning calorimetry. The resulting films exhibited a good thermal stability up to 150°C, a low extensibility and a maximum value of tensile strength of 20.33 MPa. It was found that the higher values of tensile strength were obtained for the films formed at the elevated temperatures investigated in this study. Additionally, Fourier transform infrared spectroscopy revealed the formation of hydrogen bonds between wool and glycerol leading to a good compatibility.

The results showed that wool fibers can be processed into bioplastics by a thermoplastic process. Finally, the full factorial design is an efficient method for testing the influence of operatory conditions on tensile properties.  

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Bhawani, S.A.; Hussain, H.; Bojo, O.; Fong, S.S. In: Jawaid, M.; Swain, S.K. (ed) Bionanocomposites for packaging applications. Springer, Cham (2018).

Mekonnen, T.H.; Misra, M.; Mohanty, A.K. In: Misra, M.; Pandey, J.K.; Mohanty, A.K. (ed) Biocomposites: design and mechanical performance. Woodhead Publishing (2015).

Mekonnen, T.; Mussone, P.; Khalil, H.; Bressler, D. Progress in bio-based plastics and plasticizing modifications. Journal of Materials Chemistry A 1(2013) 13379-13398.

Hernandez-Izquierdo, V.M.; Krochta, J.M. Thermoplastic processing of proteins for film formation - A review. Journal of Food Science 73 (2008) R30-R39.

Arfat, Y.A. In: Ahmed, J.; Rahman, M.S.; Roos, Y.H. (ed) Glass transition and phase transitions in food and biological materials. Wiley, Chichester (2017).

Popescu, C.; Wortmann, F.J. In: Müssig, J. (ed) Industrial applications of natural fibres: structure, properties and technical applications. Wiley, Chichester (2010).

Kuffner, H.; Popescu, C. In: Kozłowski, R.M. (ed) Handbook of natural fibres. Woodhead Publishing, Cambridge (2012).

Lewis, D.M.; Rippon, J.A. The coloration of wool and other keratin fibres. Wiley, Chichester (2013).

Ashby, M.F. Materials and the environment: eco-informed material choice. Butterworth-Heinemann, Waltham (2013).

Yamauchi, K.; Yamauchi, A.; Kusunoki, T.; Kohda, A.; Konishi, Y. Preparation of stable aqueous solution of keratins, and physiochemical and biodegradational properties of films. Journal of Biomedical Materials Research 31 (1996) 439-444. 4636(199608)31:4<439::AID-JBM1>3.0.CO;2-M

Patrucco, A.; Zoccola, M.; Consonni, R.; Tonin, C. Wool cortical cell-based porous films. Textile Research Journal 83 (2013) 1563-1573.

Ramirez, D.O.S.; Carletto, R.A.; Tonetti, C.; Giachet, F.T.; Varesano, A.; Vineis, C. Wool keratin film plasticized by citric acid for food packaging. Food Packaging and Shelf Life 12 (2017) 100-106.

Mori, H.; Hara, M. Transparent biocompatible wool keratin film prepared by mechanical compression of porous keratin hydrogel. Materials Science & Engineering C 91 (2018) 19-25.

Pavlath, A.E.; Houssard, C.; Camirand, W.; Robertson, G.H. Clarity of films from wool keratin. Textile Research Journal 69 (1999) 539-541.

Katoh, K.; Shibayama, M.; Tanabe, T.; Yamauchi, K. Preparation and physicochemical properties of compression-molded keratin films. Biomaterials 25 (2004) 2265-2272.

Barone, J.R.; Schmidt, W.F.; Liebner, C.F.E. Thermally processed keratin films. Journal of Applied Polymer Science 97 (2005) 1644-1651.

Barone, J.R.; Schmidt, W.F.; Gregoire, N.T. Extrusion of feather keratin. Journal of Applied Polymer Science 100 (2006) 1432-1442.

Reddy, N.; Chen, L.; Yang, Y. Biothermoplastics from hydrolyzed and citric acid crosslinked chicken feathers. Materials Science and Engineering C 33 (2013) 1203-1208.

Vuddanda, P.R.; Montenegro-Nicolini, M.; Morales, J.O.; Velaga, S. Effect of plasticizers on the physico-mechanical properties of pullulan based pharmaceutical oral films. European Journal of Pharmaceutical Sciences 96 (2017) 290-298.

Ahmed, A.; Qayoum, A.; Mir, F.Q. Spectroscopic studies of renewable insulation materials for energy saving in building sector. Journal of Building Engineering 44 (2021) 103300.

Kongjao, S.; Damronglerd, S.; Hunsom, M. Purification of crude glycerol derived from waste used-oil methyl ester plant. Korean Journal of Chemical Engineering 27 (2010) 944-949.

Guerrero, P.; Retegi, A.; Gabilondo, N.; de la Caba, K. Mechanical and thermal properties of soy protein films processed by casting and compression. Journal of Food Engineering 100 (2010) 145-151.

Chuaynukul, K.; Nagarajan, M.; Prodpran, T.; Benjakul, S.; Songtipya, P.; Songtipya, L. Comparative characterization of bovine and fish gelatin films fabricated by compression molding and solution casting methods. Journal of Polymers and the Environment 26 (2018) 1239-1252.

Andonegi, M.; de la Caba, K.; Guerrero, P. Effect of citric acid on collagen sheets processed by compression. Food Hydrocolloids 100(2020) 105427.

Dou, Y.; Zhang, B.; He, M.; Yin, G.; Cui, Y. The structure, tensile properties and water resistance of hydrolyzed feather keratin-based bioplastics. Chinese Journal of Chemical Engineering 24 (2016) 415-420.

Brebu, M.; Spiridon, I. Thermal degradation of keratin waste. Journal of Analytical and Applied Pyrolysis 91 (2011) 288-295.

Ricci, L.; Umiltà, E.; Righetti, M.C.; Messina, T.; Zurlini, C.; Montanari, A.; Bronco, S.; Bertoldo, M. On the thermal behavior of protein isolated from different legumes investigated by DSC and TGA. Journal of the Science of Food and Agriculture 98 (2018) 5368-5377.

Sanyang, M.L.; Sapuan, S.M.; Jawaid, M.; Ishak, M.R.; Sahari, J. Effect of plasticizer type and concentration on tensile, thermal and barrier properties of biodegradable films based on sugar palm (Arenga pinnata) starch. Polymers 7 (2015) 1106-1124.

Ullah, A.; Wu, J. Feather fiber-based thermoplastics: effects of different plasticizers on material properties. Macromolecular Materials and Engineering 298 (2013) 153-162.

Zoccola, M.; Aluigi, A.; Tonin, C. Characterisation of keratin biomass from butchery and wool industry wastes. Journal of Molecular Structure 938 (2009) 35-40.

Aluigi, A.; Zoccola, M.; Vineis, C.; Tonin, C.; Ferrero, F.; Canetti, M. Study on the structure and properties of wool keratin regenerated from formic acid. International Journal of Biological Macromolecules 41 (2007) 266-273.

Sharma, S.; Hodges, J.N.; Luzinov, I. Biodegradable plastics from animal protein coproducts: feathermeal. Journal of Applied Polymer Science 110 (2008) 459-467.

Ullah, A.; Vasanthan, T.; Bressler, D.; Elias, A.L.; Wu, J. Bioplastics from feather quill. Biomacromolecules 12 (2011) 3826-3832.


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