Hydrolysis of nylon 6 with proteolytic enzyme

Nowadays, textile processing based on biotechnology has gained importance in view of stringent environmental and industrial safety conditions. The best established application of biotechnology to textiles is the use of enzymes. These vital parts of all living organisms are organic catalysts with specific in the reaction catalyzed and substrates selectivity. Traditional chemical treatments are replaced by enzymes because of their lower product quality, higher manufacturing cost, affecting some favorable bulk properties of textiles, not easily controlling, creating harsh conditions, undesirable side effects and/or waste disposal problems, more waste, high odor process for workers and added energy consumption in textile industry. The main enzymes used in textile processing are amylases, cellulases, proteases, esterases, nitrilases, catalases, peroxidases, laccases and pectin-degrading enzymes.
Nylon 6 fabrics were first treated with different concentrations of subtilisin enzyme in aqueous solutions containing 1, 2, 4 and 6% for 80 min at 30ºC. The dyeing process was then carried out on the treated fabrics with disperse dye. A UV–Vis. spectrophotometer was used for determination of dyebath exhaustion. Disperse dye showed higher exhaustion on the enzyme treated samples. The intensity of major peaks in FTIR spectra of protease treated samples are in favor of chemical changes of the polypeptide fabric. The results of color measurement in the CIELAB system showed that the darkness of the samples increased with an increase in the enzyme percentage in the solution. The wash and light fastness properties of samples were measured according to ISO 105-CO5 and Daylight ISO 105-BO1 and discussed.