ABSTRACT:Coir fibers were modified with 1,6-hexanediol diacrylate (HDDA) using ultraviolet (UV) radiation. Concentration of HDDA, soaking time, and radiation dose were optimized and found to be 30% HDDA in methanol along with photoinitiator Irgacure-500 (2%) and 120 min of soaking time registered as the better performance (polymer loading (PL) 7%, tensile strength factor, T f ϭ 1.50). Urea of different concentrations (0.5-2%) were incorporated with 30% HDDA to monitor its effect on the properties and 1% urea produced the best results (PL ϭ 25%, T f ϭ 1.82). For the improvement of the properties, the fibers were subjected to surface treatment with potassium permanganate (KMnO 4 ) of different concentrations at various treating times. Enhanced properties (PL ϭ 86%. T f ϭ 4.42) of the fibers treated with KMnO 4 (0.05%) were obtained. The KMnO 4 treated fibers were again treated with HDDA (30%) solution along with urea (1%) and found to produce the best results (PL ϭ 100%, T f ϭ 4.5). Water uptake and degradable properties of the treated and virgin fibers were obtained.

Coir fibers were modified with 1,6-hexanediol diacrylate (HDDA) by using ultraviolet (UV) radiation. Concentration of HDDA, soaking time, and radiation dose were optimized and found to be 30% HDDA in methanol along with photoinitiator Irgacure-500 (2%) and 120 min of soaking time the better performance registered as the optimum conditions, where polymer loading (PL) was 17% and tensile strength (TS) was 50%. Urea of different concentrations (0.5-2%) was incorporated with 30% HDDA to monitor its effect on the properties and 1% urea produced the enhanced PL (25%) and TS (82%). For the improvement of the properties, the fibers were subjected to surface treatment with alkali (5% potassium hydroxide) at various mercerizing times in hot and normal conditions. Among all the mercerized fibers, fibers treated with hot alkali for 6 h and cured under optimized condition demonstrated the maximum enhancement of PL (35.5%) and TS (130%). The fibers were also subjected to acid hydrolysis for different times with different acid (H 2 SO 4 ) concentrations. Again the effect of urea (1%) on the properties of the pretreated fibers was scrutinized. Water uptake and degradable properties of the treated and virgin fibers were performed.