Chlorine retention

Basic oxides of metals such as Co, Mn, Fe, and Cu catalyze the decomposition of chlorate by lowering the decomposition temperature. Consequendy, less fuel is needed and the reaction continues at a lower temperature. Cobalt metal, which forms the basic oxide in situ, lowers the decomposition of pure sodium chlorate from 478 to 280°C while serving as fuel (6,7). Composition of a cobalt-fueled system, compared with an iron-fueled system, is 90 wt % NaClO, 4 wt % Co, and 6 wt % glass fiber vs 86% NaClO, 4% Fe, 6% glass fiber, and 4% BaO. Initiation of the former is at 270°C, compared to 370°C for the iron-fueled candle. Cobalt hydroxide produces a more pronounced lowering of the decomposition temperature than the metal alone, although the water produced by decomposition of the hydroxide to form the oxide is thought to increase chlorine contaminate levels. Alkaline earths and transition-metal ferrates also have catalytic activity and improve chlorine retention (8). 

Curing Catalysts for A Methylol Agents. Many acid-type catalysts have been used in finishing formulations to produce a durable press finish. Catalyst selection must take into consideration not only achievement of the desked chemical reaction, but also such secondary effects as influence on dyes, effluent standards, formaldehyde release, discoloration of fabric, chlorine retention, and formation of odors. In much of the industry, the chemical suppher specifies a catalyst for the agent so the exact content of the catalyst may not be known by the finisher. 

Chlorine retention, causing marked yellowing and strength loss Selection of crosslinking agents, use of chlorine free washing products... 

DMU is highly reactive finish baths have to be used in a few hours Low stability to hydrolysis, low durability to laundering High chlorine retention... 

Fewer problems with chlorine retention than U/F products... 

Chlorine retention is a special problem with amine and amide-containing finishes. When fabrics treated with these finishes are laundered with chlorine bleach, unsubstituted nitrogen atoms can react to form chloramines (Fig. 5.10). Chloramines hydrolyse to form hypochlorous acid that can decompose to materials that will degrade cellulose by significant strength loss and marked yellowing. DMDHEU products show less chlorine retention than do TMM or DMU products. Chlorine retention of A -methylol-based finishes is used for antimicrobial effects (Chapter 15.4 and Fig. 15.3 and 15.4). 

CNC SOFT C-2 provides excellent fiber softness and lubricity and is resistant to scorching and chlorine retention. 

Polymeric blend. Softener and napping assistant for cotton and cotton/polyester blends. Improves fabrics mechanical properties such as sewability and is non-yellowing and non-chlorine retentive. May be used in thermosetting resin finishes. 

Chlorine retention n. A characteristic of several resins and textile finishes whereby they retain some of the chlorine from bleach. On heating of the goods, the chlorine forms hydrochloric acid, causing tendering of the cloth. This is especially true of certain wrinkle resistant finishes for cotton and rayon. 

Cuprous cyanide (s. a. under EtMgBr) Replacement of bromine by cyano groups and chlorine Retention of configuration... 

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