Characterization of composite tiles fabricated from poly(ethylene terephthalate) and micromarble particles reinforced by glass fiber mats

Abstract Polyester composite tiles (PCT) are synthesized from PET and fabricated by compression molding using micromarble clusters as filler. Three batches of marble clusters with different size distributions are used to assess the effect of particle size on mechanical properties. In addition, tiles are cured at 40, 60, 80, 100, and 120°C to characterize the dependence of mechanical properties on cure temperature. Tiles prepared using finer marble grades yield consistently higher flexural strength and stiffness values regardless of the cure temperature. The cure temperature does not seem to have an appreciable effect on mechanical properties except for 120°C cure. Samples cured at 120°C registered a sharp drop in mechanical properties. Dynamic mechanical analysis indicates improved material damping when coarse grade marble dust is used. Prospects of improving mechanical properties are explored by reinforcing PC tiles with randomly oriented, discontinuous glass fibers. This is achieved by placing a single layer of glass fiber mat on the top and bottom tile surface. Presence of fiber mats leads to the formation of a graded particle size distribution across the mat thickness when the coarse grade marble dust is used. This distribution resulted in significant improvements in flexural strength, stiffness, and overall toughness of the tiles by enhancing the interfacial region between the glass mats and the PC tile. The mechanism of improvement is elaborated by studying the crack propagation and fracture morphology. POLYM. COMPOS., 33:1921–1932, 2012. © 2012 Society of Plastics Engineers