INFLUENCES OF CROSSLINKER AND MOLECULAR WEIGHT OF CHITOSAN ON PHYSICO-CHEMICAL PROPERTIES OF ANTIBACTERIAL TREATED COTTON FABRICS

Abstract

This study investigated the influences of crosslinking agent and molecular weight on the surface and comfort properties of cotton fabrics treated by chitosan. Two types of chitosan, with molecular weight (2.6 kDa and 187 kDa), with deacetylation degree (DD) of 75%, were used, along with two types of crosslinking agents: citric acid (CA) and dimethylol dihydroxyethyleneurea (DMDHEU). These agents were applied to cotton fabrics for antibacterial treatments. The treated cotton fabrics were evaluated using several quality indicators related to physico-chemical properties, including whiteness (according to ISO 105 J02), breathability (according to ASTM D737:2004), moisture (according to ASTM D 2495-87), and thermal and moisture resistance under steady-state conditions (according to ISO 11092). Moreover, surface features of treated samples were observed through SEM images. The results showed that the antibacterial treatment of fabrics with lower molecular weight (Mw) chitosan was more favorable for the finishing processes, although the whiteness of the treated samples was quite low. Additionally, cotton fabrics treated with the CA agent exhibited better hygroscopicity and vapor transmission, but tended to have more pronounced yellow color, compared to those treated with the DMDHEU agent. These physico-chemical findings clarified the bonding mechanism of cellulose–crosslinker–chitosan in antibacterial treated cotton fabrics.