Enzymatic scouring and low-temperature bleaching of fabrics constructed from cotton, regenerated bamboo, poly(lactic acid), and soy protein fibers was written by Spicka, Nina;Zupin, Ziva;Kovac, Janez;Forte Tavcer, Petra Eva. And the article was included in Fibers and Polymers in 2015.Category: amides-buliding-blocks This article mentions the following:
In the present study, fabrics constructed from cotton, regenerated bamboo, poly(lactic acid), and soy protein fibers were scoured with pectinase enzymes, bleached with different bleaching processes using peracetic acid (PAA), and conventionally bleached with hydrogen peroxide (HP). The enzymic scouring and bleaching with PAA have been chosen in order to minimize fiber damage and to perform the processes in more benign conditions. PAA was added to the bleaching bath in the form of a com. solution or it was produced in situ in the presence of HP with the addition of a bleach activator, tetraacetylethylenediamine (TAED), or arylesterase enzymes. The conventional process was performed at 90° in highly alk. pH media, and the bleaching processes with PAA were performed at 65° in neutral to slightly alk. pH media. The results revealed that after the enzymic scouring, the hydrophilicity of the fabrics is adequate. Compared with the cotton fibers, the regenerated bamboo and especially the poly(lactic) acid and soy protein fibers are significantly damaged during conventional HP bleaching. By contrast, bleaching with PAA revealed a strong whitening ability that is comparable to that of conventional bleaching with HP but with substantially reduced fiber damage. In the experiment, the researchers used many compounds, for example, N,N-(Ethane-1,2-diyl)bis(N-acetylacetamide) (cas: 10543-57-4Category: amides-buliding-blocks).
N,N-(Ethane-1,2-diyl)bis(N-acetylacetamide) (cas: 10543-57-4) belongs to amides. Because of the greater electronegativity of oxygen, the carbonyl (C=O) is a stronger dipole than the N–C dipole. The presence of a C=O dipole and, to a lesser extent a N–C dipole, allows amides to act as H-bond acceptors. Amides are not in general accessible by the direct condensation of amines with carboxylic acids for two reasons: first, both components are readily deactivated by a transfer of a proton from the acid to the amine and second, the hydroxy unit on the carbonyl of the acid is a relatively poor leaving group. Nevertheless, the formation of five- and six-membered rings is often surprisingly simple provided that other factors can be brought into play to assist in the condensation.Category: amides-buliding-blocks
Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics