Polypropylene fibers containing dispersed clays having improved fire performance. Part II: characterization of fibers and fabrics from PP–nanoclay blends

In this second part of a series of studies on polypropylene (PP) fibers having improved fire performance and containing nanodispersed clays we build on the observations of the first part of this work (published in Journal of Applied Polymer Science), where the need to improve dispersion of nanoclays is the key to achieve significant improvement. This paper attempts to address this issue by reporting studies of the use of several different functionalized clays in the presence and absence of compatibilizing PP copolymers and also to which the flame retardant (FR), ammonium polyphosphate (APP) has been introduced. Compounded polymer samples have been characterized using X‐ray diffraction (XRD), optical, and scanning electron microscopes, and their melt flow indices (MFI). These compounded polymers have been successfully extruded into filaments using a single screw extruder and then knitted into fabric samples. Filament physical properties are reported together with burning behaviors of fabric samples using limiting oxygen index (LOI) and flame spread tests.