Synthesis And Application Of Durable Formaldehyde-free Phosphorus Flame Retardant For Cotton Fabrics

Flame retardant finishing for cotton is always the researching emphasis as a protectivefunctional finishing. But the main problems of flame retardant for cotton at present arenon-durable property and the release of formaldehyde when produced and applied. Becauseof low toxicity to the person and environment, phosphorus flame retardants have beenshowing good anti-flaming and application foreground.Considering the above, two kinds of phosphorus flame retardants which containingreactive group were prepared- durable Phosphorus/Silicon flame retardant finishing agent SPand formaldehyde-free phosphorus flame retardant FRC-F, also the influent factors werestudied. Structure, condition of synthesis and process of reaction was analyzed using FTIR inthis thesis. Process of synthesis and application of flame retardants were simple. And it canbe applied to cotton fabric without crosslinking agents through padding, drying and curingprocess. The effect of process conditions and additives on the flame retarding results wasstudied. These are two formaldehyde-free flame retardant with reactive group-OH. The mainresearch work was summarized in the following statements:1. Dimethyl phosphonate and methyl vinyldichloridesilane were used as raw materialsfor preparation the hydroxyl containing Phosphorus/Silicon flame retardant finishingagent-SP. The results showed that the optimal processing parameters: Dimethylphosphonate(mole): methyl vinyldichloridesilane(mole)=1.5:1, reaction temperature was50℃, traction time was 24h, the dosage of catalyst was 3g AICI₃. The flame retardant wasused on cotton fabrics. An optimized procedure was determined by evaluating the effect ofprocess conditions and additives on the flame retarding results. The results showed that theoptimal processing parameters: the amount of flame retardant was 350g/L, cross-linkingagent was 60g/L, catalyst was 30g/L, triethanolamine was 20g/L, softener was 3g/L, pHvalue was 3. Good anti-flame and strength property fabrics was got on the condition of dip-pad-dip-pad, drying temperature was 100℃, curing temperature was 180℃. Flameretardant was formaldehyde-free and environmental when produced and applied. Carbonizedlength of finished cotton fabric was about 10.6cm after 30 times washing, so it can be usedas a durable flame retardant.2. A durable formaldehyde-free phosphorus flame retardant FRC-F, which wasapplicated on cotton fabric, was synthesized successfully with dimethylmethylphosphonate(DMMP), phosphoric pentaoxide and ethylene glycol-glycerol mixture.The results showed that the optimal processing parameters: DMMP(mole):P₂O₅(mole)=2:1.5,reaction temperature was 90℃, traction time was 6.0h, intermediate(mole): ethylene glycol-glycerol mixture (mole)=1:2, reaction temperature was 80℃, traction time was 2.0h. Theapplication process on cotton fabrics with FRC-F, polycarboxylic cross linking agent BTCA,catalyst NaH₂PO₂ and softener was investigated. The flame retardant of fininshed cottonfabric was improved significantly and it became more durable to laundering, Carbonizedlength of finished cotton fabric was about 9.2cm after 30 times washing. No remarkabledecrease had been found in handle and mechanical properties of the cotton fabric byadjusting the process properly. The data on research indicated that FRC-F is a durableformaldehyde-free flame retardant on cotton fabric worthy of research and development.