Effect of pH value on graft yield (Yg) of 2-(dimethylamino)ethyl methacrylate (DMAEMA) onto silk fab- rics initiated by ultraviolet rays are investigated in this paper. Three kinds of grafted silk fabrics obtained in different pH adjustment processes were characterized by DSC (differential scanning calorimetry)

TGA/DTG (thermogravim- etry analysis and derivative thermogravimetry

differential thermal analysis (DTA) and contact angel measurement. The thermal analysis results indicated that the grafted silk fabrics showed different compatibility between the silk fibroin molecules and 2-(dimethylamino)ethyl methacrylate polymers. And the crystalline structure of the grafted silk fabrics remained unchanged

or changed due to the pH adjustment process. It was found that the gel particles sized differently in solutions with the pH value adjusted in different ways and this might lead to different grafted effects of the silk fabrics.