Efficacy of cassava gel, Polyvinyl acetate and Hydroxyethyl cellulose as sizing agents for 30-cell paper egg tray

Abstract

Abstract This study was designed to examine the efficacy of three commonly available additives as sizing agents for 30-cell paper egg trays used in Southwestern Nigeria. The parameters considered were physical, mechanical and sorption properties. Waste papers were sorted, and samples macerated. 30-cell paper egg trays were produced at 5% consistency and 500 mmHg vacuum pressure. Three different additives (Cassava gel, Polyvinyl acetate, PVA and Hydroxyethyl cellulose, HEC) were utilised as sizing agents using internal and external application techniques. Cassava starch recovered from effluent from a cassava processing factory was made into gel and used at 0, 10, 20 and 30 percent; PVA used at 0, 5, 10 and 15 percent; while HEC was used at 0, 0.5, 1, and 2 percent solids concentration respectively. Waste papers were identified as Chipboard and Newsprint, having average fibre length (1.18±0.50 mm and 2.30±0.72 mm respectively), fibre diameter (22.59±5.87 µm and 41.06±11.27 µm respectively), and runkel ratio (0.63±0.50 and 0.46±0.35) respectively. The most favourable parameter showed caliper of 1.37±0.06 mm, weight of 74.80±1.72 g, moisture content of 4.48±0.19%, water absorption capacity of 253.20±8.14%, thickness swelling of 67.00±1.87%, maximum compressive load of 11.42±0.45KN, compressive strength of 0.29±0.01 N/mm², maximum tensile force of 9.98±0.13KN, and tensile strength of 33.60±0.42 N/mm respectively. Finally, Cassava gel of 10%, PVA of 5% and HEC of 0.5% solids concentrations in both application techniques best enhanced sorption, physical and mechanical properties of the PET. Dosage increase of cassava gel, PVA and HEC all had significant effect on PET tested. The recommended dosages of additives by RSM were 8.70% and 10.85% of cassava gel, 1.69% and 4.94% of PVA, and 0.36% and 0.47% of HEC for both application techniques respectively.