A series of bis-benzoxazines, prepared in high yield and purity using two synthetic procedures, is reported. Differential scanning calorimetry reveals similar temperatures for the onset of polymerisation (162-180 degrees C); the higher values representing monomers containing polar bridges or rigid backbones. Dynamic viscoelasticity data reveal glass transition temperatures for the polybenzoxazines ranging from 187 degrees C to 235 degrees C; a fluorinated polybenzoxazine consistently yields the highest T-g of the polymers studied. The latter is interesting since it is superior to many commercial benzoxazines with a relatively high T-g (235 degrees C), flexural modulus (5.0 GPa) and flexural strength (146.7 MPa), but coupled with a breaking strain (3.06%) that is uncharacteristically high for polybenzoxazines. The incorporation of fluorine results in a low dielectric loss properties (D-k = 3.71-4.12 at 10 MHz, D-f = 0.0109 - 0.0980 at 10 MHz), which are comparable with commercial polybenzoxazines, FR4 and aerospace epoxy resins and superior to commercial bismaleimides. (C) 2012 Elsevier Ltd. All rights reserved.