Thermal and mechanical behavior of cotton/vinyl ester composites: Effects of some flame retardants and fiber treatment

Abstract

Natural fibers are low-cost fibers with low density and high specific properties. These fibers are biodegradable and non-abrasive. The natural fiber composites offer unique properties comparable to those of conventional synthetic fiber composites. However, development of these composites is often hampered by weak compatibility between fibers and polymer matrix and poor thermal resistance, which often reduce their performance. This paper reports thermal properties and flammability of cotton/vinyl ester composites containing some flame retardant materials such as ammonium molybdate, aluminum trihydroxide, antimony trioxide and Chlorez tested by thermogravimetric analysis and flame retardancy. Addition of flame retardants to cotton/vinyl ester composites reduced burning rate and produced a self-extinguishing flame in some flame-resistant systems. In addition, alkali treatment of cotton fibers using 15% NaOH solution was conducted to improve compatibility of cotton fibers and vinyl ester resin. Tensile test indicated that the treated cotton fibers improved the interfacial bonding and enhanced elongation-at-break of the composites.