Kinetics of the Crosslinking Reaction of Cotton Catalyzed with Mixtures of Aluminum Salts and Tartaric Acid

Abstract

We have determined the physical properties of cotton fabrics treated with di methyloldimethyldihydroxyethyleneurea in the presence of aluminum salts, tartaric acid, or their mixtures under various curing conditions. We have also investigated the kinetics of the cellulose-DMDMDHEU reaction catalyzed by 0.015 M of various ratios of aluminum sulfate and tartaric acid mixtures in the 50 to 120°C temperature range. We calculated the specific reaction rate constant and activation parameters for the reaction, and found that the transition state complex at lower curing temperatures (<100°C) differs from that formed at higher curing temperatures (≥ 100°C). We also compared the activation parameters of a single catalyst with the values of the mixed catalyst, and measured the IR spectra of DMDMDHEU and the baked materials of DMDMDHEU + catalyst.

Crosslinking of Sulfonated Cotton Cellulose

“…Here we can see the slightly concave shape of the relationship between nitrogen content and the initial curing time in all cases, which we attribute to the time needed to raise the temperature of the fabric in the oven [5]. Sulfonated cottons are more active than unsulfonated, and the higher degree of sulfonation of the sulfonated cottons is more active than the lower one.…”

“…This result may be due to the higher absorption between the crosslinking agent and the sulfonated cellulose. Rowland et al [ 1,5,10,12,216,17] pointed out that a complex of the metal ion from the catalyst and the methylol compound is formed and (transition state) can then react with cellulose. This transition state complex may be absorbed strongly by the sulfonated cellulose fabric.…”

“…Padded fabrics were cured at 80, 90, and 100°C for different time intervals, then soaped, washed, and dried. Other modified (sample 1) and unmodified samples were padded twice to about 95% wet pickup with freshly ,prepared (2,4,6, and 8% w/w) aqueous solutions of DMDMDHEU in the presence of the aluminum sulfate/ tartaric acid catalyst [5,6] (mole ratio = 33/67 of salt/ acid) for agent distribution study. The catalyst concentration in the aqueous solutions was 0.10 times the crosslinking agent solid concentration.…”

“…Semilogarithmic plots of (%No -%N)/%No versus curing time in minutes are shown in Figure 3, where %No is a percent of the nitrogen content determined from the treated fabric by the pad-dry-cure process (that is, 95% wet pick-up, 80°C X 5 minutes, 125°C X 3 minutes; the samples are thought to be fully cured under these conditions [5]). %N is the percent of bound nitrogen after a measured time.…”

Crosslinking of Sulfonated Cotton Cellulose

“…The modified cotton samples were padded twice to about 90% wet pickup with freshly prepared aqueous solutions of DMDHEU (2, 4, 6, and 8% w/w) in the presence of the aluminum sulfate/tartaric acid catalyst [ 2,3 ] ( mole ratio = 33/67 of salt/acid). The catalyst concentration was 0.10 times the crosslinking agent solid concentration.…”