The application of halogen-free flame retardants in polyester fibers is mainly achieved through blending, intrinsic modification and surface treatment technologies. While enhancing the flame retardant performance, it is necessary to take into account the material strength, processability and cost. The following is the specific analysis:
Flame retardant technology type:
Reactive flame retardants: Such as the highly efficient halogen-free reactive flame retardant RFR, which is introduced into polyester fibers through chemical bonding, has a high flame retardant efficiency. A dosage of 3% can meet the UL-94 V-0 flame retardant standard, and has a relatively small impact on other properties of polyester, with good spinnability.
Additive flame retardants: Such as the highly efficient halogen-free additive flame retardant AFR, which is directly blended with polyester fibers, has high thermal stability, is non-toxic, requires a small addition amount, does not need to be used in combination with other flame retardants, has good flame retardant effect, and its melting point is suitable for the processing temperature of polymers.
Low-melting-point flame-retardant copolyester technology: By using the low-cost third monomer and the flame-retardant monomer RFR in combination, a low-melting-point flame-retardant copolyester with a controllable melting point between 100 and 210℃ is prepared, which is suitable for making non-woven fabrics.
Flame retardant effect:
The flame retardant performance of halogen-free flame-retardant polyester fibers is excellent. For example, the LOI (Limiting Oxygen Index) of flame-retardant PET and its nanocomposites is ≥30, reaching the UL-94 V-0 flame retardant standard.
Low-melting-point flame-retardant copolyester also has excellent flame-retardant performance, and the fiber breaking strength is ≥2.5 cN/dtex, meeting the requirements of applications such as non-woven fabrics.
Application field:
Flame-retardant PET and its nanocomposites are applicable to flame-retardant protective clothing and military uniforms, textiles in transportation vehicles, decorative fabrics for high-rise hotels, carpets and other fields.
Low-melting-point flame-retardant copolyesters are suitable for the nonwoven fabric industry and are widely used in agriculture, the automotive industry, construction, civil engineering, and healthcare, among other fields.
Technical Challenges and Solutions:
Challenge: Some halogen-free flame retardants may affect the glass transition temperature and fiber strength of polyester fibers, and have poor stability.
Solution: The PPET nanocomposites developed through nanotechnology can further enhance the flame retardant performance of the materials. Phosphorus oxide flame retardants can achieve good stability and hydrolysis resistance through flame retardant monomers containing phosphorus oxide groups or oligomers formed by the esterification of synthetic flame retardant monomers with ethylene glycol.
Environmental Protection and Cost
Halogen-free flame retardants contain no halogen elements, meet environmental protection requirements, and reduce the release of toxic substances.
The low-melting-point flame-retardant copolyester technology uses a low-cost third monomer, reducing production costs.
