| There are a lot of advantages in the PVA size. But there are two problems in the PVA desizing. First, desizing is not complete, which will influence dyeing and stamp seriously. Secondly, the waste water of the PVA desizing will bring serious pollution to environment. And the PVA size is not easily degraded, needing about 900 days to be degraded completely. So, environment pollution is the deadly weakness of the PVA size. It has been forbidden to use in many nations, and our country is reducing the PVA size dosage gradually.With the improving of environmental protectional consciousness in recent years, the traditional desizing reaction happens in acid or alkali mainly. The cost more high and the pollution more severity exist in the process. It has already not satisfied modern peoples needs. Searching a new desizing method with lower pollution and expenses with desizing effect satisfying need for later work, it has already caused the attention of many people. A modern and green environment protection technique-plasma is used in the text, and it uses oxygen as the reaction gas to preprocess PVA desizing cotton fabric. We study desizing process. Plasma treatment parameter will influence desizing effect and the physical, mechanical function of the fabric. PVA size exists on the yarn and the fabric surface with film form, PVA film as researching object is researched in the text, then to PVA desizing cotton fabric carry on research.The performance changes of weight loss rate, water-solubility treated by oxygen low temperature plasma are studied in the text. We also analyzed the surface chemical structure and surface morphology changes of the PVA film with AFM and Infrared spectra. The experimental results show that the PVA film generates surface etching and roughening after being treated by oxygen plasma. Furthermore, we found that Plasma treatment can increase the water-solubility rate to 40 percent, weight loss rate close to 1.6 percent and parts of hydroxyl group become carbonyl group and carboxyl, even water and carbon dioxide. However, chafing resistance, wettability, the breaking strength and elongation of PVA film are not changed.Based on researching for PVA film, plasma pretreatment PVA sizing cotton fabric, and it uses hot water and alkali to desize. Desizing effect will be compared with the traditional desizing. We will study plasma treatment conditions effect for desizing rate, weight loss rate, wettability, breaking strength and elongation of fabric. The experimental results show that, when it determines plasma treatment parameter. Weight loss rate and desizing rate will be considered comprehensively, and weight loss rate too high will affect desizing rate and others properties. Through plasma treating and water desizing, desizing rate will be 11.5-12.0% and be desized incompletely, when treating conditions are suitable. It can not satisfy the requirement of desizing. After plasma pretreatment, under the lower alkali concentration and shorter treating time circumstances. PVA sizing has been desized completely. The weight loss will be increased with the increasing of plasma treating time, pressure, power. Wettability, the breaking strength and elongation are slightly higher. That plasma-assisted desizing is able to meet the requirements of desizing, as well as reduce the costs and pollution, and there is still a certain fabric performance improvement. So, plasma-assisted desizing will be had broader application.
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