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N,N’-di(4-propargyloxyphenyl) phosphoramide (DPPPA) was successfully synthesized by nucleophilic substitution of 4-propargyloxy aniline and phenylphosphonyl dichloride. The structure of DPPPA was characterized by nuclear magnetic resonance (NMR) and Fourier transformation infrared (FT-IR) analyses. DPPPA was used to mix with bisphenol A of dicyanate ester (BADCy) and bisphenol E of dicyanate ester (BEDCy) in solution. The DPPPA modified cyanate esters (BADCy/DPPPA and BEDCy/DPPPA) were obtained after the solvent was evaporated under vacuum. The thermal properties, limited oxygen index (LOI) and mechanical properties of the modified cyanate esters were studied. The results show that the residual yield at 800 ℃ in air of the cured BADCy/DPPPA and cured BEDCy/DPPPA increase from 0 to 33% and 26% in comparison with the cured neat cyanate esters, and the LOI of the cured modified cyanate esters reach 39.7% and 35.4%, but the glass transition temperatures of the cured modified cyanate esters decrease by 19 ℃ and 24 ℃, respectively. The flexural and tensile strength of the cured BADCy/DPPPA are 123 MPa and 45 MPa, which are higher than that of the cured BEDCy/DPPPA. The impact strength of the cured BADCy/DPPPA and BEDCy/DPPPA are 11 kJ/m² and 14 kJ/m², respectively. The water absorption of the cured neat cyanate esters decreases with blended with DPPPA. [ABSTRACT FROM AUTHOR]

Crosslinker is one of the most important factors that dominate the recognition performance of molecularly imprinted polymer (MIP). In this research, MIP was prepared by using bisphenol A (BPA) as the template molecule, α-methacrylate (MAA) as the functional monomer and bisphenol A dimethylacrylate (BPDMA) as the crosslinker, respectively. The resulted MIP was also compared with those obtained by using dimethyl glycol acrylate (EGDMA) and N, Nmethylene diacrylamide (BIS) as the crosslinking agents, respectively. The results indicated that the MIP material prepared using BPDMA as the crosslinker gave rise to the best imprinting factor (5.32) and adsorption capacity (5.05 mg/g), which were far superior to those already reported BPA imprinted materials. The imprinting factors of the materials prepared using EGDMA and BIS as the crosslinking agents were 1.41 and 1.45, respectively, and the adsorption capacities were 0.96 mg/g and 2.79 mg/g, respectively. Thus, cross-linker plays an important role in the recognition property of MIP. The resulted MIP was further applied to enrich BPA from milk. The recovery rate was 95.0%-98.9% and the relative standard deviation was 3.5%-4.2%. These results indicated that the prepared imprinted material could be used for the selective enrichment of BPA from complex systems. [ABSTRACT FROM AUTHOR]

The third monomer dipropargyl bisphenol A（BPA）and bisphenol A bisazide（DGEBA-N3）were synthesized,and were used to modify the polytriazole PTA coatings,ultimately leading to modified coatings of B-PTA and D-PTA.The curing process and thermal properties of the coatings of B-PTA and D-PTA were studied by differential scanning calorimetry（DSC）,FT-IR,dynamic mechanical thermal analyses（DMA）,and thermogravimetric analysis（TGA）.Meanwhile,mechanical properties and anticorrosion performance were investigated at 25°C.The results showed that the glass transition temperature（Tgof the coatings of B-PTA and D-PTA was reduced,and the thermal stability（T（d5））was basically unchanged in comparison with the coatings of PTA.The shear strength,adhesive force,impact resistance and flexibility were increased,while the hardness was basically unchanged.Moreover,corrosion resistance of the coatings of B-PTA was improved in salt spray box,10% H2SO4 solution and 5% NaCl solution,and reduced in 10% NaOH solution;and corrosion resistance of the coatings of D-PTA was improved in salt spray box,10% H2SO4 solution,5% NaCl solution and 10% NaOH solution [ABSTRACT FROM AUTHOR]