ANALYSIS OF THE EFFECT OF QUANTITY OF CATALYST AND LAMINATE THICKNESS ON CURING TIME IN PRODUCTION OF GLASS REINFORCED POLYESTER COMPOSITE

Abstract

Production process of reinforced plastic composite materials involves the curing of a thermosetting resin through an exothermic chemical reaction. Research studies have shown that the exothermic heat released during curing process and whose degree varies with laminate thickness has an effect on curing time. The curing time for the resin dictates the rate of production and quality of product. This study aimed at investigating the effect of laminate thickness and quantity of catalyst on the curing time during the production of glass reinforced polyester composite. This research utilized unsaturated polyester resin, Methyl Ethyl Ketone Peroxide catalyst and E-glass fiber reinforcement for sample preparation. Different amount of catalyst ranging from 0.5% to 5% were dispensed on the polyester resin used in making laminate samples of thicknesses ranging from 1mm to 3mm and hand lay-up technique was used to produce sample panels. Curing time of the samples was determined according to the ASTM standards while data analysis was done using the statistical analysis software. Results showed that curing time reduced with increase in both laminate thickness and quantity of catalyst which could be attributed to heat evolved during polymer cross linking heat that was more pronounced in thicker laminate and higher catalyst levels. Statistical analysis showed that the catalyst level had a significant effect on curing of glass reinforced polyester composites compared with laminate thickness or an interaction between the two. It was concluded that the curing time of glass- reinforced polyester composites depended on the laminate thickness and quantity of catalyst.