Preparation Of Non-Formaldehyde Durable Press Reagent And Its Application On Cotton

Formaldehyde released during anti-crease finishing process with polymethylol amides, not only do harms to the operators, but also pollute environment. The worst thing is that the cotton fabrics treated with this kind of agents continually release formaldehyde in the course of storage and wear. Therefore, it is the inevitable developing trend to use formaldehyde-free finishing agents. Polycarboxylic acids as a kind of formaldehyde-free finishing agents are promising. Among the polycarboxylic acids, BTCA has remarkable anti-crease effect;however, no enterprises would like to use it in a large industrial scale because of its high cost. CA has poor finishing effect: finished fabrics becoming seriously yellow, and not being durable washing, though its price is at low side. PMA is highly promising because of its sound finishing effect, non-formaldehyde, and being less expensive.In this study, PMA was prepared by adopting maleic acid as monomer in presence of sodium hypophosphite as catalyst and potassium persulphate as initiator, which was proved by FT-IR. PMA synthesized by this method was colorless and could be directly used as durable press finishing agent without purification. At the same time, the synthesis process was optimized;the application formulations and conditions were studied;and the optimum technology was chosen. The performance of the cotton fabrics treated separately with PMA, polymaleic anhydride and BTCA were compared. As a result, PMA with wrinkle recovery angle being 271°, strength retention being 68%, and whiteness being 83.58% has the same effect as BTCA, and has better finishing effect than polymaleic anhydride. The finishing effects of mixture polycarboxylic acids of PMA/BTCA were also analyzed. The study showed that anti-crease properties of the cotton fabric treated with PMA/BTCA are significantly improved. Furthermore, the strength retention is enhanced by adding boric acid in the finishing bath of PMA/BTCA.Durable press finishing by means of ionic crosslinking such as CHTAC/CAA, CC/CAA and CHTAC/BTCA were also studied. The result showed that anti-crease properties of the cotton fabrics treated by ionic crosslinking are enhanced, moreover, the strength retentions are not reduced. Especially, the cotton fabrics treated with CHTAC/BTCAhave significantly anti-crease properties with wrinkle recovery angle being 270° and strength retention being 70%, higher than those treated with BTCA alone.It is concluded that PMA, which synthesized with the above-mentioned method, is an excellent formaldehyde-free finishing agent and has a bright prospect. As for the ionic crosslinking process, a novel method of durable press finishing needs further research.