The novel benzoxazine monomers, DPA-Bz and MDP-Bz from renewable diphenolic acid (DPA), which mimics the structure of bisphenol A (BPA), were synthesized by traditional approaches. The structure and purity of the monomers was confirmed by FTIR, H-1 NMR, and C-13 NMR spectra. The thermally activated polymerization of the MDP-Bz and DPA-Bz afforded thermosetting polybenzoxazines with higher T-g's, 270 degrees C and 208 degrees C respectively, and higher crosslinking density compared to BPA-Bz, due to the transesterification or esterification reactions occurred during curing process. These reactions are in accordance with the number of independent reactions determined analyzing by SVD the chemical rank of the IR spectra data matrices recorded along the homopolymerization reactions monitored at 200 degrees C. Spectral and concentration profiles of the active chemical species involved in these processes were obtained by MCR-ALS. (C) 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 49: 1219-1227,2011