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°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°C to 235°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°C), flexural modulus (5.0GPa) and flexural strength (146.7MPa), 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 10MHz, D f =0.0109 – 0.0980 at 10MHz), which are comparable with commercial polybenzoxazines, FR4 and aerospace epoxy resins and superior to commercial bismaleimides.