Corn husk fibers

Keywords Agro-residues, banana bunch fibers, biocomposites, biodegradable, corn husk fibers, natural fibers, okra bast fibers, renewable... 

Yilmaz [11] investigated the effects of alkali extraction treatment parameters on properties of corn husk fibers. Yilmaz [13] compared corn husk fibers produced by water retting, alkalization and enzyme treatment. Huda and Yang [7] produced composites from corn husk fibers and polypropylene (PP) and investigated their flexural, impact resistance, tensile and sound absorption properties. 

Figure 11.1 Examples of some agro-residual fibers, (a) okra fiber (From 1. M. De Rosa et al. Composites Science and Technology, 2011 [14]. With Permission from Elsevier) (b) banana fiber (From A. V. R. Prasad, K. M. Rao, G. Ragavinirasulu, Indian Journal of Fibre and Textile Research, 2009 [30]. With permission from Indian Journal of Fibre and Textile Research)-, (c) corn husk fiber [31].

Corn husk fibers the tenacity of which is around 25% lower than that of jute can produce more durable and tough composites than jute due to the elongtaion ratio and work of rupture which are 13 times and 7 times greater than that of jute, respectively [7]. 

Decrease in water absorption behavior is reported to occur with alkalizing of okra bast and banana stem and bxmch fibers [5,26]. Ganan et al. [26] reported an increase in contact angle and decrease in surface free energy. Yilmaz [11] also found a decrease in moisture content of corn husk fibers with the increase in concentration and duration of alkalization. The decrease in moisture content might be due to the reduction in hydroxyl groups. 

Yilmaz [13] reported that alkaline extracted corn husk fibers posed higher thermal resistance with the onset of the major degradation step of210 - 225°C compared to water retted and enzyme treated corn husk fiber with that of 185°C. This might be due to the stronger effect of alkalization in removing extra-cellulosic material. She also reported lower yellowness of alkalized corn husk fibers compared to water retted ones which also... 

There have been limited amount of research devoted to enzymatic treatment of agro-residual fibers [12,13,58]. When comparing different extraction procedures including water retting, alkalization and enzyme treatment, Yilmaz [13] foimd the strongest and finest corn husk fibers to be produced by a fiber production route of water retting followed by enzyme treatment. 

Reddy et at [20] used used sodium sulfite and ethylenediamine to delignify the corn husk fibers. The treatment decreased the lignin content from 6% to 0.1% and the diameter of the fibers was reduced by 35% and the modulus of the fiber was increased by 50%. 

S. Huda and Y. Yang, Chemically extracted corn husk fibers as reinforcement in hght-weight poly(propylene) composites. Macromol. Mater. Eng. 293, 235-243 (2008). 

N.D. Yilmaz, Effect of chemical extraction parsuneters on corn husk fibers chcffacteris-tics. Indian J. Fibre Text. Res. 38, 29-34 (2013). 

N. D. Yilmaz, Effects of enzymatic treatments on the mechanical properties of corn husk fibers. 7. Text. Inst. 104,396-406 (2013). 

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