Proban flame retardant principle and process

I. Introduction
    Proban Flame Retardant process originated in the United Kingdom Aowei company, the main ingredient is a four-hydroxymethyl phosphorus trichloride (THPC) and amide low molecular pre-shrink body. After the fabric is padded with Proban flame retardant, the precondensate formed by the THPC and amide permeates into the amorphous regions and interstices of the fibers. NH3 was subsequently cross-linked with the methylol groups in the pre-condensed form during ammonia smoked, forming a flame-retardant polymer inside the fiber and then stabilized by oxidation. Therefore, Proban lawns treated fabric soft, strong loss is small, basically maintaining the comfort and durability of the fabric. Suitable for all kinds of protective clothing, bedding, decorative items and children's flame retardant pajamas, is an important method of durable cotton fabric flame retardant finishing.
    Second, flame retardant principle
    Phosphorus-containing compounds cause cellulose fibers to undergo dehydration during the thermal process. Phosphorus-containing flame retardants in the fiber pyrolysis temperature range first decomposed into non-volatile phosphoric acid or polyphosphoric anhydride and cellulose hydroxyl (-OH) dehydration reaction, the fiber carbonization. Fabrics padded with Proban flame retardants produce a P-N synergistic effect due to the formation of a highly cross-linked phosphorus / nitrogen dichloride in the interior of the cellulose during the ammoxidation process. P-N bond performance (polarity) is higher than the P-O bond, so that phosphorus compounds and -OH reactivity, resulting in efficient and durable flame retardant properties.
    Third, the process
    Padding flame retardant finishing liquid (room temperature) → pre-bake (100 ~ 120 ℃) ​​→ Ammonia smoked → oxidation washing → drying (130 ~ 140 ℃) → pre shrink → finished product.
    Fourth, the process conditions
    1, flame retardant concentration determination: In the process of developing the process, should be based on the thickness of the fabric and the size of the liquid rate to determine, generally for thin fabrics, fabrics with Proban amount should be more than 40% fabric weight, Medium-thick fabrics can be 35 to 40%.
    2, moisture content of the size:
    Fabric after padding fire retardant drying, there must be a certain degree of humidity to NH3 and ammonia on the fabric when the flame retardant crosslinking reaction, play a flame retardant effect, and washability. General moisture content should be controlled between 12 to 16%, left and right tidal error can not exceed 2
%, Otherwise it is easy to produce the left and right color difference, so the production process should be monitored at any time the size of moisture content, and adjusted at any time, too low moisture content will lead to inadequate crosslinking, flame retardant effect is not washing, containing too much moisture Lead to excessive crosslinking, feel stiff, color changes are also large.
    3, ammonia flow to determine:
    From the front of the reaction point of view, the amount of ammonia gas consumption per kilogram of flame retardants theoretically is certain, but the actual production process should be a little over the amount of cross-linking sufficient. Usually ammonia flow control in the 350 ~ 500L / min, the flow is too small, inadequate crosslinking, flame retardant effect washability poor; flow is too large, resulting in waste and ammonia spills, resulting in poor working conditions. Practical applications, but also should be based on the thickness of the fabric and the amount of flame retardant to adjust the flow of ammonia in order to achieve the best flame retardant effect.
    4, the concentration of oxidant
    Flame retardant cured by ammonia to make it more stable, you must P +3 oxidation P +5, usually by padding H2O2 method to achieve, the amount of H2O2 should be based on the thickness of the fabric, the amount of flame retardant Size to be set. Usually the amount of 30 ~ 35% concentration. Oxidation padding speed can not be too fast, in order to ensure adequate H2O2 left on the fabric, and then through the air oxidation and soap washing out, the oxidation time should not be too long, otherwise it will reduce fabric strength.
    V. Conclusion
    Flame retardant cotton fabrics treated by PUR had excellent flame retardant effect and reached the requirements of international GB-8965-98 <Flame-retardant Protective Clothing>, and also reached the requirements of EU "EN470, EN470-1, EN533, EN531, BS5852" And other standards, through the European Community, the United States, the United Kingdom flame retardant fabric first-class product testing, its low toxicity and environmental protection on the human body safe, breathable, moisture permeability, soft and comfortable to wear, has now been accepted by countries in the world.

How to buy good quality and cheap flame retardant fabrics, fluorescent fabrics, three functional fabrics Teflon and other functional fabrics?
Choose Xinxiang Yu Long Textile Co., Ltd. , we will provide you with the best fabrics, we will also provide you with the supply of flame retardant overalls.