Sizing Without PVA Is A Systematic Project.

Wu Changhong, Jiangsu new salt spinning Group Co., Ltd.

In order to further promote the process of sizing without PVA, enterprises are concentrating on the selection of sizing agents. After application and practice, the sizing performance of modified starch slurry is continuously improving.

However, due to the fluctuation of yarn quality and instability of pulp quality and improper application, the expansion of green sizing works is hindered.

For this reason, the quality of raw yarn is required to be stable. Following the principle of "similarity compatibility", we should select slurry size, advocate simplifying the matching components of slurry, and emphasize the optimization of sizing process, thus becoming the best way to promote green sizing without PVA.

In 2010, the new salt spinning group of Jiangsu, in order to reserve green sizing experience, carried out the green sizing without PVA on the pure cotton combed C14.6tex * C14.6tex 523 * 378167 anti rust cloth. By sizing, optimizing the size matching and adjusting the sizing process according to the yarn quality, no PVA sizing was achieved.

In practice, our experience is that textile sizing completely takes the place of PVA.

Sizing is the basis for sizing.

There are differences in performance between various modified starch sizes, and this difference affects

In addition, simplification of slurry matching components is the precondition for improving sizing performance.

The slurry matching multiple components can meet the needs of yarn sizing, but it is not clear which slurry size is conducive to the improvement of sizing performance. Which kind of slurry hinders the performance of other sizing agents.

Moreover, it is easy to overfill the warp yarn, causing unnecessary waste and increasing the complexity of the sizing process.

Therefore, a simplified component optimization matching method is adopted to match the slurry so that the main sizing agent can show the advantages and disadvantages in performance through sizing application, which not only contributes to the performance of slurry, but also improves the sizing performance.

Raw yarn quality affects sizing without PVA.

At present, there are

In order to ensure the sizing performance of warp yarn is stable, the yarn strength and evenness are not only needed to control the tension of the yarn, but also the sizing process is needed to increase the sizing rate, and make up for the yarn's reinforcement and wear resistance and hairiness.

More importantly, it is necessary to improve the matching quality of the slurry and maintain the weaving quality of the yarn with the performance of the film, so as to improve the weaving efficiency.

However, the most convenient, quick and reliable way to improve the quality of pulp matching is to increase the proportion of PVA slurry in the slurry.

Therefore, to achieve sizing without PVA, improving yarn quality is the most important condition.

Control of yarn elongation is the key.

After grafting starch to replace PVA, the film formed on warp is still hard and brittle, especially the fracture elongation of the film is worse than that of the PVA film.

If the elongation of the sizing is not controlled by the quality of the original yarn, it will affect the stability of the sizing performance and even destroy the performance of the film.

In order to control the elongation of different raw yarn quality by on-line detection, it is an effective way to find out the sizing performance of different modified starch with new thinking.

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Reasonable control of moisture regain of sizing yarn

When the grafted starch is used as a substitute for PVA sizing, the starch is the main form of starch matching. In order to make the film pliable and elastic, it is necessary to control the moisture regain of the sizing yarn according to the temperature and humidity of the weaving environment and the fiber characteristics, so as to avoid the hardening and crispness of the film and affect the production efficiency of the loom.

Because the viscosity of the grafted starch is low, the wetting speed of the fiber is obviously accelerated. This will increase the heat shrinkage of the wet sizing yarn when the dryer is drying. If the moisture regain of the sizing agent is not controlled, it is easy to form the adhesive failure at the junction of the film and the fiber and affect the integrity of the film.

In addition, the humidity of the membrane will change with the change of ambient temperature and humidity.

Therefore, the hygroscopic rate of the film will change with the change of weaving temperature and humidity.

To control the sizing moisture regain, the steam pressure can be controlled and the surface temperature of the dryer can be stabilized.