Synthesis and characterization of novel biobased benzoxazines from cardbisphenol and the properties of their polymers

Two types of novel biobased benzoxazine monomers (named as CBB and CBF, respectively) from cardbisphenol were synthesized by a solventless method. The chemical structure of the monomers was confirmed by FTIR, H-1 NMR and C-13 NMR spectra, etc. FTIR and DSC showed that CBB and CBF were thermally initiated and polymerized via ring-opening polymerization. As a result, the thin polybenzoxazine (named as PCBB and PCBF, respectively) films can be obtained. Dynamic mechanical analysis (DMA) indicated that the glass transition temperatures (T-g) of PCBB and PCBF were 94 degrees C and 121 degrees C, respectively. Thermogravimetric analysis (TGA) demonstrated that the thermal stability of PCBF was better that of PCBB. Both PCBB and PCBF had low humidity absorption values.