High performance NBR/fly ash composites prepared by an environment-friendly method

Fly ash (FA) is a solid waste from coal-fired power stations, which can cause serious environmental problems without further treatment. Although FA has been successfully utilized in building materials, the reuse of FA in the polymer industry has remained a great challenge due to the difficulty in organically-modifying the smooth surfaces of FA particles. In this study, by introducing tannic acid (TA, a naturally occurring plant polyphenol), nitrile butadiene rubber (NBR)/FA/TA composites were prepared via a simple environment-friendly method. The properties of the products were thoroughly investigated and experiments showed that the TA incorporation into NBR/FA composites resulted in formation of hydrogen bonds among NBR, FA, and TA, leading to dramatic improvement in surface adhesion between NBR and FA. As a consequence, the tensile strength of the NBR/20FA/0.4 TA composite was similar to 110.4% larger than that of NBR/20FA composite, thus opening a new route to large-scale practical use of FA in the polymer industry.