Abstract
Plastics composites consist of intimate mixtures of resin and fillers or reinforcements. According to the definitions proposed by the American Society for Testing and Materials (ASTM-D-883), a filler is a relatively inert material added to a plastic to modify its strength, permanence, working properties, or other qualities, or to lower costs. In contrast, according to ASTM-D-883, a reinforced plastic is defined as one with some strength properties greatly superior to those of the base resin, resulting from the presence of high-strength fillers imbedded in the composite. The reinforcing fillers are usually fibers, fabrics, or mats made of fibers. The plastic laminates are the most common and strongest type of reinforced plastics.