The Factors that Affect the Durability of the Cotton Flame Retardant Fabric

1. The amount of flame retardant

 

In the flame retardant finishing, the amount of flame retardant plays the key role on the flame retardant finishing effect and the mechanical properties of the after finishing fabric.

In a certain range, with the increase of the flame retardant amount, the flame retardant effect of the fabric will increase accordingly. However when the flame retardants content reaches a certain amount, the flame-retardant effect will no longer improved and also the hand feel of the fabric become stiff with the increasing of flame retardants. The whiteness and tearing strength will decrease. If the amount of the flame retardants is too less, the crosslinking is insufficient, so the fabric has poor wash resistance.

 

2, The volume of crosslinking agent

 

In the flame retardant finishing process, the cross-linking agent can crosslink the flame retardants and cellulose molecules to form a network structure, so that can reinforce and flame retardant fabric washability, and the film-forming property of the crosslinking agent on the fabric surface determines the hand feel of the fabric , tear strength, wash resistance directly.

 

The crosslinking agent has small effect on the fabric flame retardant property, but has great effect on the hand feel of the fabric, tear strength and durability. By crosslinking with the fiber macromolecules, the cross-linking agent bound covalently with the flame retardants to improve flame retardant washing resistance. So if the amount of crosslinking agent is too small, the film-forming property will not good, thus the poor wash resistance; if the amount of crosslinking agent is too much, the formed network structure makes fabric feel stiff, the strength will decline. Therefore, we need to balance the relationship among the hand feel, strength and wash resistance when determine the amount of the crosslinking agent.

 

3, The amount of catalyst

 

In the flame retardant finishing process, the catalyst may enable the crosslinking agent cross linked with the flame retardants and the cellulose molecules rapidly during the baking process to improve the flame retardant effect. However, the catalyst is acidic and it will effect the strength of the fabric, so the dosage need to be controlled strictly.

 

Suitable catalysts can improve the fabric flame retardant effect. But if the amount is excessive, causing a serious decline in fabric strength, whiteness, hand feels slightly. Due to the cotton fabric is alkaline resistant, not acid resistant. We should give full consideration to fabric strength when determine the catalyst usage level. And also after printing, neutralized with an alkali immediately to reduce the damage on fabric strength.

 

4, The baking temperature and time

 

It goes without saying that the baking temperature and time will effect the flame-retardant fabric greatly. All the covalently crosslink caused by the reaction among the flame retardant and the Cellulose macromolecule and crosslinking agent must be completed in the baking process. The appropriate baking temperature and baking time can make the film forming very well, to enhance the wash resistance.

 

If the baking temperature is too high and the baking time is too long, the fabric will become brittle and the tear strength will decline. If the Baking temperature is too low, the flame retardant and the crosslinking agent could not react sufficiently, thus the fabric will has poor flame retardant wash resistance.