Enhanced mechanical, UV protection and antimicrobial properties of cotton fabric employing nanochitosan and polyurethane based finishing

In the present investigation, nanochitosan-polyurethane dispersions (NCS-PUs) were prepared via polymerization process and applied on polyester cotton fabric (PCF) as a finishing agent. A prepolymer of PU with NCO functionality was synthesized using isophorone diisocyanate (IPDI), polyethylene glycol (PEG) and DMPA (2, 2-dimethylol propionic acid) was extended with NCS. The structural characterization of NCS-PUs was monitored by FTIR analysis. Pad dry cure technique was adopted for the application of NCS-PUs on pre-dyed and printed PCF samples. The PCF samples (dyed and printed) were tested for antibacterial activity, Ultraviolet protection factor (UPF) and tear & tensile strength properties. The UPF values in case of 10% PUB1 to PUB6 application was recorded to be 40.5, 42.30, 44.10, 47.50, 54.30 and 37.80, respectively, whereas the tensile strength improved up to 8.1% in case of 10% NCS-PUs application and these value was increased when 20% NCS-PUs was applied. Antimicrobial activity was evaluated against Gram positive and negative strains (S. aureus and E. coli). The PCF samples finished with NCS-PUs showed higher antimicrobial activity, protection against UV and tensile strength versus unfinished sample with NCS-PUs. Results revealed that the NCS-PUs significantly improved the properties of PCF (both of dyed and printed samples), hence, the NCS-PUs can be applied as finishing agent to enhance the antimicrobial activity along with protection from UV radiation.