Abstract: To study the subsidiary composition of natural green cotton, the pigment was extracted with ethanol. Then the extractive was analyzed with GC-MS and compared with white cotton. The volatile substances in the extractive of natural green cotton and white cotton were found to be nearly the same and the main volatile substance is 2-Methyl allylamine, 2-Cyclohexen-1-ol,2-methyl-5-(1-methylethenyl)-,1-propanoate, Diaminomaleonitrile, 2-(Acryloyloxy)ethyl Methacrylate and 2,4-Di-tert-butylphenol with 2-Cyclohexen-1-ol,2-methyl-5-(1-methylethenyl)-,1-propanoate to be the most one. Meanwhile, a substance called Methacrylic acid isobutyl ester is found to be in natural green cotton, which does not exist in white cotton. The results showed that natural green cotton has really different constituents with white cotton. The effect of those constituents on the color of natural green cotton needs further study.

Key words: natural green cotton , ethanol extrac , GC-MS , isobutyl methacrylate