Poly(benzoxazine-urethane)/graphene oxide [poly(Bz-PU)/GO] composites were successfully prepared by blending benzoxazine (Bz) with graphene oxide (GO) and isocyanato (NCO)-terminated polyurethane prepolymer (PU), followed by thermally activated polymerization of the blends. The network was formed via the mutual reaction and intermolecular interaction among the hydroxyl of GO, NCO groups of PU and phenolic hydroxyl of Bz. The toughness shown from SEM images and tensile properties of polybenzoxazine (PBz) plastic composites can effectively be improved by alloying with PU and GO. The onset curing temperature and exothermic peak maximums of the polymerization obtained from differential scanning calorimetry decreased resulted from the GO addition. The thermogravimetric analysis showed that the incorporation of 0.5 wt% of GO slightly improved the thermal stability of poly(Bz-PU)/GO composites. Additionally, the storage modulus improved and the glass transition temperature (Tg) increased gradually as the increasing GO content not beyond a certain amount. Finally, the exothermic peaks of the polymerization were shifted to lower temperature, and the thermal stability increased for the ternary composites as the number average molecular weights (Mn) of polyol decreased.

Hierarchical porous N-doped carbon spheres featuring a combination of micropores, mesopores and macropores as well as tuneable properties were synthesised using dopamine as a carbon precursor and triblock copolymers (F127, P123 and F127/P123 composites) as templates via direct polymerisation-induced self-assembly. The structures and textures of these materials were characterised using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, N₂ adsorption–desorption isotherm analysis, Fourier-transform infrared spectroscopy, Raman spectroscopy and X-ray photoelectron spectroscopy. The sample synthesised at an F127:P123 molar ratio of 1:3 (NCS-FP3) exhibited the highest surface area (463 m²/g) and pore volume (0.27 cm³/g). The hydrophobic/hydrophilic molar ratios of the templates were adjusted to control the morphology of the corresponding micelles and hence the porous structures and morphologies of the carbon spheres, which exhibited high CO₂ capture capacities (2.90–3.46 mmol/g at 273 K and 760 mmHg) because of their developed microporous structures and N doping. Additionally, NCS-FP3 exhibited an outstanding electrochemical performance, achieving a high specific capacitance (328.3 F/g at a current density of 0.5 A/g) and outstanding cycling stability (99.2% capacitance retention after 10,000 cycles). These high CO₂ capture and electrochemical performances were ascribed to the beneficial effects of pore structures and surface chemistry features.

Graphene oxide (GO) was functionalized by polyether amine (PEA) via two methods which were one-pot modification in acetone (GON) and two steps with the intermediate product of GOCO-Cl generated (GONS). There were more PEA successfully grafted onto GO for GONS than GON. The onset polymerization temperatures of the benzoxazine (Bz) composites decreased by the inclusion of 1 wt% of GO, GON or GONS. Thermal stability of the polybenzoxazine (PBz) composites was significantly improved indicated from the increase of weight loss temperature. T₁₀, T₂₀ and T₅₀ values of the composites with GONS were higher than that of the others. Toughness of PBzs may be enhanced by the incorporation of nanofillers, and GONS had stronger interfacial interaction with PBz matrix than GON.

Aliphatic ternary benzoxazine (Bz) based from triamine with long chain, as well as flexible binary Bz, was successfully synthesized, which was named as BzT and BzD respectively. The corresponding polybenzoxazines (PBz) rooting from BzT and BzD (PBzT and PBzD) respectively and their copolybenzoxazines (co-PBzs) were obtained to improve the mechanical and thermal properties via chemical cross-linking. The onset polymerization temperatures of the copolymers decreased from 189.1°C to 143.9°C, and the exothermic peak temperature reduced significantly from 232.5°C to 217°C as the content of BzT increased from 0 wt% to 100 wt% in the copolymers. The value of char yield at 800°C increased gradually from 21.5 wt% for PBzD to 28.7 wt% for PBzT. The increasing crosslink density resulted higher glass transition temperatures and improved storage moduli in glassy region because of the introduction of BzT.

C₁₆H₂₀MnN₁₀O₈, monoclinic, P2₁/c (no. 14), a = 11.1178(7) Å, b = 12.7838(6) Å, c = 15.6649(10) Å, β = 105.692(6)°, V = 2143.4(2) ų, Z = 4, R _gt (F) = 0.0638, ωR _ref (F ²) = 0.2034, T = 293 K.

In this current work, two new-style DOPO-containing benzoxazines based on polyether-urea were successfully synthesized by a modified version via three-step procedures, and the corresponding polybenzoxazines with high toughness and flame retardancy were obtained by thermal activated polymerization. The single and double DOPO-containing benzoxazines were named as BzD1 and BzD2, respectively. The corresponding polymers followed were named as PBzD1 and PBzD2, respectively. The curing behaviors of the two new benzoxazines were investigated by differential scanning calorimetry. The thermal and mechanical properties of the materials were evaluated by TGA and dynamic mechanical analysis. The flame retardant properties were elucidated via limiting oxygen index (LOI). The toughness properties were expressed by bending tests. The results showed that the Yc for PBzD1 and PBzD2 were approximately 22.2% and 24%, respectively, distinctively higher than the value 2.57% of pristine polybenzoxazine PBz1, at 800 °C in N₂ atmosphere. The Tgs of PBzD1 and PBzD2 distinctly increased by 42.8 °C and 20 °C, respectively, in comparison to −35 °C for pristine PBz1. The LOI values of PBzD1 and PBzD2 were 28.5 and 31, respectively. The length and weight-loss of PBzD1 and PBzD2 samples were significantly less than that of PBz1 when they were burned in the air environmental condition. The burning behavior demonstrated that the flame retardant properties was obviously improved as DOPO was introduced. All of the three specimens of PBz1, PBzD1 and PBzD2 presented excellent flexible property.