Green natural rubber-g-modified starch for controlling urea release

► Natural rubber-g-cassava starch was synthesized by using potassium sulfate as a catalyst. ► The tensile strength of modified NR in the presence of starch 50 phr was highest ► The NR-g-ST membrane displays very effective to control release of urea fertilizer ► The NR-g-ST membrane easily degrade in soil.