accord with our previous work (Riyajan, Intharit et al.,2012). For the NR-g-CSt, C-H stretching at 2965, 2928 cm−1, C C Hstretching at 1659 cm−1, CH3 deformation at 1378 cm−1, and C CH bending at 843 cm−1were found in the FTIR spectra (See Fig. 2(I)).