Effects of Surface Hydrophobicity on Functionalization of Oleic Acid on Bombyx mori Silkworm Cocoons

Abstract:

The objective of this study is to provide a method which allows introduction of functional groups onto silk cocoon surface. Plasma irradiation is straight-forward, relatively noninvasive and requires minimal chemical reaction steps to alter surface hydrophilicity of polymeric materials. Introduction of oleic acid on pristine and air-zero irradiated silkworm (Bombyx mori) cocoons was carried out via acid-catalyzed esterification. The reaction was confirmed by ATR-FTIR spectroscopy. Functionalization of oleic acids onto silkworm cocoons favors hydrophilic surface. In addition to the acid-catalyzed esterification, amide hydrolysis takes place as a side reaction. This reaction leads to formation of hydrophilic carboxylic acids and amines. The change in hydrophilic functionalities leads to an increase in cocoon wettability as confirmed by contact angle measurements.

• Periodical: Key Engineering Materials (Volume 718)
• Pages: 120-125
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.718.120
• Online since: November 2016
• Authors: Kaewta Jetsrisuparb*, Krit Pooritorn, Apisit Maungsean, Pornnapa Kasemsiri, Trinh Cao, Prinya Chindaprasirt
• Keywords: Acid Catalyzed Esterification, Oleic Acid, Plasma Irradiation, Silk

References

[1] T. Desmet, R. Morent, G.N. De, C. Leys, E. Schacht, Dubruel, Nonthermal plasma technology as a versatile strategy for polymeric biomaterials surface modification: a review, Biomolecules, 10 (2009) 2351-2378.

DOI: 10.1021/bm900186s

[2] M. Roy, S.K. Meena, T.S. Kusurkar S.K. Singh, N.K. Sethy, K. Bhargava, S. Sarkar, M. Das, Carbondioxide gating in silk cocoon, Biointerphases, (2012) 7-11.

DOI: 10.1007/s13758-012-0045-7

[3] F. Chen, F. Vollrath, D. Porter, Structure and physical properties of silkworm cocoons, J R Soc Interfac. 9 (2012) 2299-2308.

DOI: 10.1098/rsif.2011.0887

[4] J. Zhang, R. Rajkhowa, J.L. Li, X.Y. Liu, X.G. Wang, Silkworm cocoon as natural material and structure for thermal insulation, Mater. Design. 49 (2013) 842 – 849.

DOI: 10.1016/j.matdes.2013.02.006

[5] N.P.C. Horrocks, F. Vollrath, C. Dicko, The silkmoth cocoon as humidity trap and waterproof barrier, Comp Biochem Phys A. 164 (2013) 645 – 652.

DOI: 10.1016/j.cbpa.2013.01.023

[6] L. Cabrales, N. Abidi, Microwave plasma induced grafting of oleic acid on cotton fabric surfaces, Appl Surf Sci. 258 (2012) 4636-4641.

DOI: 10.1016/j.apsusc.2011.12.130

[7] S. Photong, V. Boonamnuayvitaya, Preparation and characterization of amine-functionalized sio2/tio2 films for formaldehyde degradation, Appl Surf Sci. 255 (2009) 9311 – 9315.

DOI: 10.1016/j.apsusc.2009.07.021

[8] R. Molina, J.P. Espinós, F. Yubero , P. Erra, E A.R. González, XPS analysis of down stream plasma treated wool: Influence of the nature of the gas on the surface modification of wool, Appl Surf Sci. 252 (2005) 1417 – 1429.

DOI: 10.1016/j.apsusc.2005.02.147

[9] G. Borcia, C.A. Anderson, N.M.D. Brown, Surface treatment of natural and synthetic textiles using a dielectric barrier discharge, Surf Coat Tech. 201 (2006) 3074 – 3081.

DOI: 10.1016/j.surfcoat.2006.06.021

[10] G. Li, H. Liu, T. Li, J. Wang, Surface modification and functionalization of silk fibroin fibers/fabric toward high performance applications, Mater Sci Eng. 32 (2012) 627 – 636.

DOI: 10.1016/j.msec.2011.12.013

[11] S. Photong, V. Boonamnuayvitaya, Enhancement of formaldehyde degradation by amine functionalized silica/titania films, J Environ Sci. 21 (2009) 1741–1746.

DOI: 10.1016/s1001-0742(08)62482-1

[12] S.S. Banerjee, M.V. Joshi, R.V. Jayaram, Treatment of oil spill by sorption technique using fatty acid grafted sawdust, Chemosphere. 64 (2006) 1026–1031.

DOI: 10.1016/j.chemosphere.2006.01.065

[13] G. Socrates, Infrared and Raman Characteristic Group Frequencies: Tables and Charts 3rd ed. Chichester: John Wiley and sons, (2001).

DOI: 10.1002/jrs.1238