THE INVESTIGATION OF STRUCTURE-FLAMMABILITY RELATIONSHIPS OF POLYPHOSPHONATES BY PLS ANALYSIS

To date many studies have been focused on the development of fire retardant mechanism and estimation of polymer flammability. In this analysis a series of 28 polyphosphonates has been investigated by Partial Least Square (PLS) methodology using previously calculated descriptors as independent variables, and the limiting oxygen index (LOI) as dependent variable. R and S polyphosphoester stereoisomers were previously derived using molecular mechanics calculations. Reliable statistics R-Y(CUM)(2) = 0.879 (for R series); R-Y(CUM)(2) =0.809 (for S series), and Q((CUM))(2) = 0.840 (for R series); Q((CUM))(2) = 0.776 (for S series) are obtained. The HATS6v (GETWAY) descriptor is the most relevant for both models, having the best VIP (Variables Importance in the Projection) value: VIPHATS6v = 1.320 (for R series) and VIPHATS6v = 1.353 (for S series). The PLS model obtained for the R stereoisomers was more predictive compared to the S stereoisomer one.