9,9-Bis(4-hydroxyphenyl)xanthene (BHPX), a bisphenol monomer, was synthesized in 82% yield from xanthenone in a one-pot, two-step synthetic procedure. Four novel aromatic poly(ether ketone)s (PEKs) based on BHPX were prepared via a nucleophilic aromatic substitution polycondensation with four difluorinated aromatic ketones. The polycondensation proceeded in tetramethylene sulfone in the presence of anhydrous potassium carbonate and afforded the new cardo PEKs in nearly quantitative yields with inherent viscosities of 0.77-0.85 dL/g. High molecular weight PEKs having number-average molecular weights (M n 's) in the range of 38,900-40,600 g/mol with the polydispersity index ranged from 1.97 to 2.06 are all amorphous and show high glass transition temperatures ranging from 210 C to 254 C, excellent thermal stability, and the temperatures at the 5% weight loss are over 538 C with char yields above 60% at 700 C in nitrogen. These new PEKs are all soluble in polar aprotic solvents such as N-methyl-2-pyrrolidone and N, N 0 -dimethylacetamide and could also be dissolved in chloroform and tetrahydrofuran. All the polymers formed transparent, strong, and flexible films with tensile strengths of 78-84 MPa, Young's moduli of 2.54-3.10 GPa, and elongations at break of 14-18 %.

Borophosphate glasses with compositions of (48-x)P2O5-(12+x)B2O3-14CaO-20MgO-1Na2O-5Fe2O3 (where x=0, 3, 8 mol%) were prepared via a melt-quenching process. The effects of replacing P2O5 with B2O3 on the structural, thermal, degradation properties and cytocompatibility were investigated. Fourier Transform Infrared (FTIR) spectroscopy analysis confirmed the existence of BO3 triangular units and BO4 tetrahedral units within all the glasses with an increase of B/P ratio from 0.25 to 0.5. The BO4 units within the glass structure were observed to cause an increase in density (ρ) as well as glass transition (Tg) temperature and to decrease the crystallisation temperature (Tc). A decrease in thermal stability which indicated by process window was also observed in the case of substitution of P2O5 with B2O3. Degradation analysis of the glasses indicated that the dissolution rate increased with the addition of B2O3. The decrease in the thermal stability and chemical durability were attributed to the increase of BO3 units, which could increase crystallisation tendency and be easily hydrolysed by solution. The effect of boron addition on the cytocompatibility of the glasses was analysed using Alamar Blue and Alkaline Phosphatase (ALP) assays and DNA quantification. MG63 osteosarcoma cells cultured in direct contact with the glass samples surface for 14 days showed better cytocompatibility, compared to the Tissue Culture Plastic (TCP) control group. In summary, the glass formulation with 12 mol% B2O3 presented the best cytocompatibility and thermal stability, thus could be considered for continuous fibre fabrication in future research and downstream activities.

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A new diamine, 4-(4-trifluoromethylphenyl)-2,6-bis(4-aminophenyl)pyridine, was synthesized and used in the preparation of the fluorinated polyamides with inherent viscosities of 0.67–0.96 dL g−1 by direct polycondensation with aromatic dicarboxylic acids. The obtained polyamides have good solubility in many organic solvents such as N-methyl-2-pyrrolidinone, dimethylacetamide (DMAc), and tetrahydrofuran and exhibited glass transition temperatures between 275°C and 301°C, 10% weight loss temperatures ( Td10s) ranging from 502°C to 516°C, and char yields of 51–61% at 800°C under nitrogen atmosphere. Flexible and strong polymer films cast from DMAc solutions showed tensile strengths of 77.4–93.2 MPa, elongations at break of 9.2–14.3%, and initial moduli of 2.06–2.82 GPa. The polymer films also had good dielectric properties with dielectric constants of 3.22–3.50 (1 M Hz) and dissipation factors of 3.20–3.96 × 10−3, and acceptable electrical insulating properties, as well as low water uptake between 1.26% and 1.78%, and high transparency with an ultraviolet–visible absorption cutoff wavelength in the range of 330–371 nm. The remarkable combined features ensure these polymers to be ideal candidate materials for advanced microelectronic industry and other related applications.

A series of new cardo poly(ether imide)s bearing flexible ether and bulky xanthene pendant groups was prepared from 9,9-bis[4-(4-aminophenoxy)phenyl]xanthene with six commercially available aromatic tetracarboxylic dianhydrides in N,N-dimethylacetamide (DMAc) via the poly(amic acid) precursors and subsequent thermal or chemical imidization. The intermediate poly(amic acid)s had inherent viscosities between 0.83 and 1.28 dL/g, could be cast from DMAc solutions and thermally converted into transparent, flexible, and tough poly(ether imide) films which were further characterized by X-ray and mechanical analysis. All of the poly(ether imide)s were amorphous and their films exhibited tensile strengths of 89-108 MPa, elongations at break of 7-9%, and initial moduli of 2.12-2.65 GPa. Three poly(ether imide)s derived from 4,4 0 -oxydiphthalic anhydride, 4,4 0 -sulfonyldiphthalic anhydride, and 2,2-bis(3,4-dicarboxyphenyl))hexafluoropropane anhydride, respectively, exhibited excellent solubility in various solvents such as DMAc, N,N-dimethylformamide, N-methyl-2-pyrrolidinone, pyridine, and even in tetrahydrofuran at room temperature. The resulting poly(ether imide)s with glass transition temperatures between 286 and 335 C had initial decomposition temperatures above 500 C, 10% weight loss temperatures ranging from 551 to 575 C in nitrogen and 547 to 570 C in air, and char yields of 53-64% at 800 C in nitrogen.