Thermal Stability And Flame Retardancy Of PET Fabrics Treated With Collagen Contained Combinations

Poly (ethyleneterephthalate) (PET) fiber has been used in many areas such as clothing, bags, tents and other outdoor supplies due to its attractive characteristics such as high strength, good dimensional stability, and chemical stability and so on. However, its high flammability and serious melt dripping during combustion are still inadequate for many industrial applications. Collagen is a kind of protein, containing aromatic amino acids and phosphorus, which could be used as flame retardants for textiles.This work introduced collagen contained flame retardant formulations to PET fabric by dip-padding or coating methods.The first part of this paper reports the introduction of the collagen combined with ammonium polyphosphate (APP) and ammoniumsulfamate (AMS) to PET fabrics by dip-pad finishing treatment. Flammability evaluation by limiting oxygen index (LOI) and vertical burning tests shows that LOI value of treated fabric sample can be increased from 20.6 to 25.3, and the damaged char length is reduced to only 3 cm. Thermal behavior analysis of the PET fabric samples by thermogravimetric analysis (TGA) shows that the treatment can decrease the initial decomposition temperature and significantly reduce the dripping tendency. The heat release rate (HRR) of treated PET fabric is decreased by 46% compared to that of the pure PET fabric. The morphology observation of the char residue by scanning electron microscopy (SEM) demonstrates that the char formation can be enhanced by the presence of COL/APP/AMS. FTIR spectroscopy shows that the char residue of treated samples is more stable than that of the pure sample. It has been suggested that collagen could be an effective alternative to flame retardants current used in textile finishing.The second part of this paper introduced a new hydrosol system which was synthesized by copolymerization of vinyl compounds (AM or VTMS) and collagen in water, which was coated on the surface of ammonium polyphosphate (APP). The coated APP was introduced to the surface of PET fabric by roller coating. The coating layer formed on PET fabric surface were observed by SEM and its chemical groups were reflected from ATR-FTIR spectra. TGA results documented more char was kept in the modified PET fabric. Char analysis by ATR-FTIR showed the char residue of treated samples was more stable than that of the pure sample. The flame retardancy of PET fabric was significantly improved by the coating.The last part of this paper introduced a new hydrosol system which was synthesized by copolymerization of acrylamide (AM) and vinyl trimethoxysilane (VTMS) in water. APP was wrapped by the AM-VTMS hydrosol. The coating layer formed on PET fabric surface was observed by SEM and its chemical groups were reflected from ATR-FTIR spectra. TGA results documented more char was formed in the modified PET fabric. Char analysis by ATR-FTIR and EDS showed P and Si elements remained in the residue after modification. The flame retardancy of PET fabric was improved by the AM-VMTS/APP coating.