Preparation of a Salt-free Dyeing Auxiliary Agent HBP-ECH and Its Application in Silk Fabric Dyeing with Reactive Dyes

Hyperbranched polymer containing chloromethyl group(HBP-ECH)on the surface was synthesized by addition reaction with epoxy chloropropane(ECH)and hyperbranched poly amide-amine(HBP-NH 2),and was subsequently applied in silk fabric salt-free dyeing with reactive dyes. The optimum technological condition for HBP-ECH synthesis is as follows:molar ratio of hyperbranched poly amide-amine to epoxy chloropropane 1∶10,molar ratio of sodium hydrate to epoxy chloropropane is 1 ∶ 6,reaction temperature 30 ℃,and reaction time 4 h. Infrared spectrometric analysis verified the existence of chloromethyl group on surface of HBP-ECH. The silk fabric modified by HBP-ECH was subsequently dyed with salt-free reactive dye. The results showed that the dyed silk fabric presented K/ S value similar to the unmodified silk fabric after conventional dyeing,good color fastness,and slight change in shade.