Flame retardant and hydrophilic coatings on undyed and dyed polyamide 6.6 textiles: Clarifying the processing and performance

This work was intended to clarify if the dyeing treatment could modify the functional properties of white substrate as well as the surface finishing would alter the initial color of dyed textiles. Thus, in this work, a kind of surface coating was applied to modify the flame retardant and hydrophilic properties of both the undyed (white) and dyed polyamide 6.6 (PA6.6) textiles using some novel compounds like chitosan (CS), montmorillonite (MMT), sodium alginate (ALG) and phytic acid (PA) in a quadralayer (QL) or a hexalayer (HL) fashion. The obtained results revealed that the dyed fabric samples exhibited better flame retardancy and hydrophilicity compared to the undyed one; indicating the dyeing treatment contributed in improving the functional properties. For example, the 5HL-deposited dyed fabric sample (i.e., PA6.6-D-5HL) showed a maximum reduction in the peak heat release rate (pHRR) by 32% and the 7.5QL-deposited dyed fabric sample (i.e., PA6.6-D-7.5QL) brought a water contact angle (WCA) value of 0°. However, this kind of surface finishing caused a slight loss in depth of color for the dyed fabric samples.