Journal of Applied Polymer Science, Vol.127, No.4, 2952-2959, 2013
Jute Fabric Reinforced Engineering Thermoplastic Sandwich Composites. I. The Effect of Molding Time
Jute fabric-reinforced sandwich composites were fabricated using engineering thermoplastics. The jute fabrics were pre-coated with thermosetting resin to improve their thermal resistance before molding of the composites. Thermal gravimetric analysis (TGA) studies revealed that the resin coated fabrics decomposed at higher temperature than the uncoated jute. The onset of degradation of the coated fibers also falls between that of jute fibers and the thermoset resins. This indicates the presence of good interfacial bonding between jute fibers and both resins. Isothermal TGA studies revealed that jute could withstand brief exposure to higher temperature at 270 and 290 degrees C. The sandwich composites were fabricated at 270 degrees C by compression molding for 1.5 and 3 min in each case, and then characterized by flexural, tensile and morphological studies, i.e., SEM and optical microscopy. The uncoated jute fabric yielded composites of superior mechanical properties even with 3 mins molding at 270 degrees C which is close to the degradation temperature of uncoated jute fibers. This is an indication that it is feasible to prepare jute fiber filled engineering polymer composites provided the exposure time at high temperature during processing does not exceed 3 mins as determined by TGA isothermal studies. SEM studies revealed strong fiber/matrix interfacial bonding between jute and the thermoset resins while the inferior mechanical properties of the resin coated sandwich composites could be attributed to the poor interfacial bonding between the already cured thermoset coating and the matrix based on optical microscopy of the polished cross-sections. (C) 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 127: 2952-2959, 2013
Keywords:jute fabric;thermosets;engineering thermoplastics;sandwich composites;thermogravimetric analysis