Abstract: | A series of plastic materials from recycled polyethylene (PE) and oyster‐shell powder were prepared to test their fire‐retardant properties with an aim of finding a practical way of waste recycling. Oyster‐shell powder was found to be mainly composed of calcium carbonate and it decomposed to calcium oxide and carbon dioxide at temperature higher than ~800°C, thus preventing fire from access of oxygen by the produced carbon dioxide. This fire‐retardation mechanism is environmental‐friendly, since another available method, the inclusion of halogen‐containing compounds, normally generates toxic chemicals like dioxine during incineration. To improve mechanical properties of this composite material, surface of oyster‐shell powder was coated with cetyltrimethylammonium bromide (CTAB). Flame retardation and the mechanical properties of these composite resins were analyzed. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1583–1589, 2006 |