Recently,azobenzene-4,4'-dicarboxylic acid(ADCA)has been produced gradually for use as an organic synthesis or pharmaceutical intermediate due to its eminent performance.With large quantities put into application ...Recently,azobenzene-4,4'-dicarboxylic acid(ADCA)has been produced gradually for use as an organic synthesis or pharmaceutical intermediate due to its eminent performance.With large quantities put into application in the future,the thermal stability of this substance during storage,transportation,and use will become quite important.Thus,in this work,the thermal decomposition behavior,thermal decomposition kinetics,and thermal hazard of ADCA were investigated.Experiments were conducted by using a SENSYS evo DSC device.A combination of differential iso-conversion method,compensation parameter method,and nonlinear fitting evaluation were also used to analyze thermal kinetics and mechanism of ADCA decomposition.The results show that when conversion rate α increases,the activation energies of ADCA's first and main decomposition peaks fall.The amount of heat released during decomposition varies between 182.46 and 231.16 J·g^(-1).The proposed kinetic equation is based on the Avrami-Erofeev model,which is consistent with the decomposition progress.Applying the Frank-Kamenetskii model,a calculated self-accelerating decomposition temperature of 287.0℃is obtained.展开更多
A one-dimensional(1 D) coordination polymer, [Cd2(TFBPDC)2(ad)2(CH3 OH)2]n(1), based on the 3,3’,5,5’-tetrafluorobiphenyl-4,4’-dicarboxylate(TFBPDC2-) and adenine(ad) ligands, was synthesized. Compound 1 crystalliz...A one-dimensional(1 D) coordination polymer, [Cd2(TFBPDC)2(ad)2(CH3 OH)2]n(1), based on the 3,3’,5,5’-tetrafluorobiphenyl-4,4’-dicarboxylate(TFBPDC2-) and adenine(ad) ligands, was synthesized. Compound 1 crystallizes in the triclinic system, space group P1 with a = 9.7067(3), b = 9.9501(3), c = 11.6903(4) ?, α = 93.036(3), β = 107.793(3), γ = 107.107(3)°, V = 1014.77(6) ?3, Z = 2, C40H26F8N10O10Cd2, Mr = 1183.51, Dc = 1.937 g/cm3, μ = 1.160 mm-1, F(000) = 584, the final R = 0.0284 and wR = 0.0635 for 3791 observed reflections with Ⅰ> 2s(I). In 1, a pair of adenine(ad) ligands bridge two octahedrally coordinated Cd(Ⅱ) atoms to form a dinuclear [Cd2(ad)2] unit, which is linked by TFBPDC2- to generate a 1 D double chain. The neighboring chains are connected by N-H×××O hydrogen bonds to give a two-dimensional(2 D) layer, which is further linked by the O-H×××N hydrogen bonds to give a three-dimensional(3 D) supramolecular framework. IR spectrum, thermogravimetric analysis, and powder X-ray diffraction of 1 were provided. Compound 1 shows luminescent emission.展开更多
基金supported by National Natural Science Foundation of China(51974166).
文摘Recently,azobenzene-4,4'-dicarboxylic acid(ADCA)has been produced gradually for use as an organic synthesis or pharmaceutical intermediate due to its eminent performance.With large quantities put into application in the future,the thermal stability of this substance during storage,transportation,and use will become quite important.Thus,in this work,the thermal decomposition behavior,thermal decomposition kinetics,and thermal hazard of ADCA were investigated.Experiments were conducted by using a SENSYS evo DSC device.A combination of differential iso-conversion method,compensation parameter method,and nonlinear fitting evaluation were also used to analyze thermal kinetics and mechanism of ADCA decomposition.The results show that when conversion rate α increases,the activation energies of ADCA's first and main decomposition peaks fall.The amount of heat released during decomposition varies between 182.46 and 231.16 J·g^(-1).The proposed kinetic equation is based on the Avrami-Erofeev model,which is consistent with the decomposition progress.Applying the Frank-Kamenetskii model,a calculated self-accelerating decomposition temperature of 287.0℃is obtained.
基金Supported by the National Natural Science Foundation of China (No. 21661014)Natural Science Foundation of Jiangxi Province (20171ACB20008 and 20181BAB203001)。
文摘A one-dimensional(1 D) coordination polymer, [Cd2(TFBPDC)2(ad)2(CH3 OH)2]n(1), based on the 3,3’,5,5’-tetrafluorobiphenyl-4,4’-dicarboxylate(TFBPDC2-) and adenine(ad) ligands, was synthesized. Compound 1 crystallizes in the triclinic system, space group P1 with a = 9.7067(3), b = 9.9501(3), c = 11.6903(4) ?, α = 93.036(3), β = 107.793(3), γ = 107.107(3)°, V = 1014.77(6) ?3, Z = 2, C40H26F8N10O10Cd2, Mr = 1183.51, Dc = 1.937 g/cm3, μ = 1.160 mm-1, F(000) = 584, the final R = 0.0284 and wR = 0.0635 for 3791 observed reflections with Ⅰ> 2s(I). In 1, a pair of adenine(ad) ligands bridge two octahedrally coordinated Cd(Ⅱ) atoms to form a dinuclear [Cd2(ad)2] unit, which is linked by TFBPDC2- to generate a 1 D double chain. The neighboring chains are connected by N-H×××O hydrogen bonds to give a two-dimensional(2 D) layer, which is further linked by the O-H×××N hydrogen bonds to give a three-dimensional(3 D) supramolecular framework. IR spectrum, thermogravimetric analysis, and powder X-ray diffraction of 1 were provided. Compound 1 shows luminescent emission.
