Infrared spectroscopy studies of the cyclic anhydride as the intermediate for the ester crosslinking of cotton cellulose by polycarboxylic acids. III. Molecular weight of a crosslinking agent

Abstract

SYNOPSISPolycarboxylic acids have been used as nonformaldehyde crosslinking agents for cotton fabrics to replace the traditional N-methylol reagents. In this research, we compared 1,2,3,4-butanetetracarboxy lic acid (BTCA) with poly(maleic acid) (PMA) as crosslinking agents for cotton cellulose. BTCA and PMA have similar molecular structures with carboxyl groups bonded to their molecular backbones, and both form five-membered cyclic anhydride intermediates during a curing process. However, BTCA is a more effective crosslinking agent for cotton cellulose than PMA. This is mainly attributed to the differences in the mobility of the anhydride intermediates to access the cellulosic hydroxyl groups during a curing process. The mobility of the anhydride intermediate of PMA is reduced due to its molecular size and multiple bonding between a PMA molecule and cellulose. Consequently, more anhydride and less ester are detected on the cotton fabric treated with PMA than on the fabric treated with 13TCA. The amount of the unreacted anhydride intermediate on the fabric treated with PMA is reduced whereas the amount of ester is increased when another hydroxyl-containing compound of low molecular weight is present. Thus, the infrared spectroscopy data show a clear link between the molecular weight of a polycarboxylic acid and its effectiveness for crosslinking cotton cellulose. c 1997 .John Wiley & Sons, Inc. Keywords: cellulose q cotton q crosslinking q esterification q infrared spectroscopy q molecular weight c polycarboxylic acids,

Polycarboxylic acids as crosslinking agents for grafting cyclodextrins onto cotton and wool fabrics: Study of the process parameters

“…This result could be unexpected considering its low yield of esterification with cellulose (in the absence of CD) compared with that of the other two PCAs of this study. We agree with the interpretation proposed by Yang and Wang18 that the reactivity of this macromolecular PCA is affected by comparison with that of the low molecular weight PCA. On the contrary, as presented in Figure 8, despite its low reactivity towards the support, PAA is a better linking agent to CD than BTCA and CTR.…”

Anti-crease finishing of cotton fabrics based on crosslinking of cellulose with acryloyl malic acid

“…3, when curing temperature increased from 140 • C to 180 • C, two distinct bands appeared at 1850 cm −1 and 1780 cm −1 . The bands are due to the symmetric and asymmetric carbonyl stretching vibration modes, respectively, of a 5-membered cyclic anhydride (Yang, 1991(Yang, , 1993Yang & Wang, 1996a, 1996b, 1997Pretsch et al, 2009). It is evident that AMA can form 5-membered anhydride under elevated temperatures.…”

“…to the carbonyl (>C O) stretching vibration of carboxylic acid and ester bonds overlapped on fabrics (Yang & Wang, 1996a, 1996b, 1997. Sharp absorbance peak around 1725 cm −1 broadened after curing, curve(b), indicating that the carboxylic acid group reacted with hydroxyl or some other groups and new carbonyl (>C O) absorbance peak appeared around 1730 cm −1 .…”

Modification of cotton fabrics with a hydrolysed organotrialkoxysilane/metal alkoxide system: multifunctionalisation and mordant dyeing

“…BTCA/SHP‐pretreated cotton fabrics are prepared by reacting BTCA with cellulosic material, applying SHP as catalyst. It is assumed that, via a five‐membered cyclic anhydride, ester bonds are formed between the carboxyl groups of BTCA and the hydroxyl groups of the cellulose, thus imparting crease resistance to the cotton fabric (Figure a) . The formation of these ester groups is confirmed by the FTIR spectrum, as presented in Figure (curve d).…”