Preparation and characterization of fire resistant PLA fibers with phosphorus flame retardant

摘要

The fire resistant poly(lactic acid) fibers with polysulfonyldiphenylene phenyl phosphonate flame retardant were prepared by melt spinning. The rheology property and spinnability of samples were measured by a capillary rheometer and recording the number of fiber breakage during a 30-min melt spinning. The thermal stability and combustion behaviors of fibers were investigated by Thermogravimetric Analysis, Limiting Oxygen Index and Vertical Burning tests, respectively. It was found that the flame retardation and anti-dripping performance of PLA were distinctly improved by OP. The pyrolysis behavior of fibers was tested by a Pyrolysis-Gas Chromatography-Mass Spectrometry, the structure and degree of graphitization of char residue were analyzed by Scanning Electronic Microscopy and Raman Spectroscopy. The results suggested that OP can promote the forming of char layer on the surface of PLA matrix during burning. The miscibility and spinnability of PLA was negatively affected by OP and the breaking strength of FR-PLA fibers dropped from 3.30 to 2.30 cN/dtex at the presence of 10 wt. % OP.