Fabrication and analysis of physico-mechanical characteristics of NaOH treated PALF reinforced LDPE composites: Effect of gamma irradiation

Abstract

Agro wastage pineapple leaf fiber (PALF) was treated with different weight/volume (w/v) concentrated (0.5, 3, 5, 7, and 10%) sodium hydroxide (NaOH) at 50 °C for 30 min. The corresponding values of weight loss, tensile properties, and density were evaluated. PALF treated with 7% NaOH showed considerably improved physico-mechanical properties. The treated fibers were used as randomly oriented reinforcement in low-density polyethylene (LDPE) filled bio-composite by maintaining a 1:1 ratio in terms of weight. The composite fabrications were done by heat press molding. Then the five categories of the sample were irradiated with gamma (Co-60) radiation beneath different doses (2.50–10.00 kGy) to increase the compatibility of fiber-matrix bonding. These irradiated samples were prepared for determining the different physico-mechanical properties such as tensile strength (TS), tensile modulus (TM), elongation at break percentage (EB%), bending strength (BS), bending modulus (BM), and impact strength (IS). Gamma dose of 7.50 kGy irradiated samples demonstrated the overall best result. SEM images of 7% NaOH treated PALF reinforced LDPE composites were analyzed at tensile fracture surface to understand the fibers pull out and fiber-matrix interface. Furthermore, the water absorption performance of the mentioned composite was also investigated at different day intervals. FTIR was used to explicate the changes of functional groups of PALF and those composites due to NaOH treatments and different levels of gamma doses respectively. TGA was performed to explore the comparatively enhanced thermal performance of 7% NaOH treated PALF containing composite sample irradiated at 5.00, 7.50, and 10.00 kGy gamma doses.