Two highly soluble aromatic polyimides were synthesized successfully from a diamine with two tert-butyl groups （MBTBA） and dianhydrides with a thioether or sulfone moiety （DTDA and DSDA）. Both of them showed excel...Two highly soluble aromatic polyimides were synthesized successfully from a diamine with two tert-butyl groups （MBTBA） and dianhydrides with a thioether or sulfone moiety （DTDA and DSDA）. Both of them showed excellent solubility in common solvents such as chloroform, tetrahydrofuran and dioxane at the room temperature. The numberaverage molecular weight was 6.0× 10^4 and 8.3 ×10^4 according to gel permeation chromatography relative to a polystyrene standard, and the polydispersity index was 1.80 and 1.82 respectively. The glass-transition temperatures of them were 286℃ and 314℃ （or 315℃ and 358℃） respectively, as measured by differential scanning calorimetry （or dynamic mechanical analysis）. The 5% weight loss temperature of both was near 490℃ in N2 by therrnogravimetric analysis. These results indicated that the tert-butyl pendent groups reduced the interactions among polymer chains and the thioether or sulfone moiety was flexible which may improve their solubility in conventional organic solvents without the loss of thermal stability. Transparent and flexible films of the two polyimides were obtained via solution casting. The MBTBA-DTDA membrane had higher storage moduli than those of the MBTBA-DSDA membrane.展开更多
Organo-soluble alicyclic polyimides (ALPIs) were synthesized from an alicyclic dianhydride, 1,8-dimethyl-bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride (DMEA) and several multialkyl-substituted 4,4'-d...Organo-soluble alicyclic polyimides (ALPIs) were synthesized from an alicyclic dianhydride, 1,8-dimethyl-bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride (DMEA) and several multialkyl-substituted 4,4'-diaminodiphenylmethane compounds, including 3,3'-dimethyl-4,4'-diaminodiphenyt methane (DMDA), 3,31,5,5'-tetramethyl-4,4'-diaminodiphenyl methane (TMDA) and 3,3',5,5'-tetraethyl-4,4'-diaminodiphenylmethane (TEDA). For comparison, the aromatic polyimides (ARPIs) were synthesized from the aromatic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA) and the same diamines. The ALPIs exhibited better solubility and transparency, but worse thermal stabilities and mechanical properties than those of the ARPIs. And the ALPIs could be dissolved in common organic solvents, such as N-methyl-2-pyrrolidinone (NMP), N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), chloroform, tetrahydrofuran, m-cresol and so on. The ALPI films had an UV-Vis cut-off at 320 nm and a transmittance of higher than 80% in the visible region. In addition, the ALPIs showed thermal decomposition temperatures (T-d) of about 450degreesC, which was nearly 100degreesC lower than that of the ARPIs.展开更多
A new aromatic asymmetrical ether diamine, 1,4-bis（3＇,4’-diaminophenoxy）benzene 3 was synthesized in three steps, using hydroquinone as starting material. A new aromatic polyimide containing asymmetrical diaryl et...A new aromatic asymmetrical ether diamine, 1,4-bis（3＇,4’-diaminophenoxy）benzene 3 was synthesized in three steps, using hydroquinone as starting material. A new aromatic polyimide containing asymmetrical diaryl ether segments was prepared from the resulting diamine with 4,4＇-oxydiphthalic anhydride （ODPA） via a conventional two-step thermal or chemical imidization method. The resulting polyimide exhibits high thermal resistance, excellent solubility, film-forming capability, high mechanical strength and modulus.展开更多
A new kind of aromatic diamine monomer containing pyridine unit,2,6-bis[4-(4-aminophenoxy)phenoxy]pyridine(BAPP),was synthesized in three steps,using hydroquinone as starting material.A novel pyridine-containing polyi...A new kind of aromatic diamine monomer containing pyridine unit,2,6-bis[4-(4-aminophenoxy)phenoxy]pyridine(BAPP),was synthesized in three steps,using hydroquinone as starting material.A novel pyridine-containing polyimide was prepared from the resulting diamine BAPP with 4,4 -oxydiphthalic anhydride(ODPA) via a conventional two-step thermal imidization method.The resulting polyimide exhibits excellent solubility,film-forming capability and high thermal resistance.展开更多
A novel class of aromatic polyimide-silicone segmented copolymer was synthesized with α, ω-bis (γ-aminopropyl) polydimethyldiphenylsiloxane (APMPS) as a silicone segment precursor, from which the segmented polyamic...A novel class of aromatic polyimide-silicone segmented copolymer was synthesized with α, ω-bis (γ-aminopropyl) polydimethyldiphenylsiloxane (APMPS) as a silicone segment precursor, from which the segmented polyamic acid-b-silicone intermediate could be prepared simply with DMF as solvent. The segmented copolymer displays microphase separation and exhibits improved antithrombogenicity, which depends mainly upon both the content level and the DP of the silicone segment. Thermal stability and mechanical property of the copolymer are between that of the aromatic polyimide and the silicone, and also relate to both the content level and the DP of the silicone segment.展开更多
基金supported by the National Basic Research Program(No.2009CB930400)National Natural Science Foundation of China(Nos.50873058,50633010)Shanghai Leading Academic Discipline Project(No.B202)
文摘Two highly soluble aromatic polyimides were synthesized successfully from a diamine with two tert-butyl groups （MBTBA） and dianhydrides with a thioether or sulfone moiety （DTDA and DSDA）. Both of them showed excellent solubility in common solvents such as chloroform, tetrahydrofuran and dioxane at the room temperature. The numberaverage molecular weight was 6.0× 10^4 and 8.3 ×10^4 according to gel permeation chromatography relative to a polystyrene standard, and the polydispersity index was 1.80 and 1.82 respectively. The glass-transition temperatures of them were 286℃ and 314℃ （or 315℃ and 358℃） respectively, as measured by differential scanning calorimetry （or dynamic mechanical analysis）. The 5% weight loss temperature of both was near 490℃ in N2 by therrnogravimetric analysis. These results indicated that the tert-butyl pendent groups reduced the interactions among polymer chains and the thioether or sulfone moiety was flexible which may improve their solubility in conventional organic solvents without the loss of thermal stability. Transparent and flexible films of the two polyimides were obtained via solution casting. The MBTBA-DTDA membrane had higher storage moduli than those of the MBTBA-DSDA membrane.
基金This work was supported by the National Natural Science Foundation of China under the Grant for Distinguished YoungScholars (No. 59925310).
文摘Organo-soluble alicyclic polyimides (ALPIs) were synthesized from an alicyclic dianhydride, 1,8-dimethyl-bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride (DMEA) and several multialkyl-substituted 4,4'-diaminodiphenylmethane compounds, including 3,3'-dimethyl-4,4'-diaminodiphenyt methane (DMDA), 3,31,5,5'-tetramethyl-4,4'-diaminodiphenyl methane (TMDA) and 3,3',5,5'-tetraethyl-4,4'-diaminodiphenylmethane (TEDA). For comparison, the aromatic polyimides (ARPIs) were synthesized from the aromatic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA) and the same diamines. The ALPIs exhibited better solubility and transparency, but worse thermal stabilities and mechanical properties than those of the ARPIs. And the ALPIs could be dissolved in common organic solvents, such as N-methyl-2-pyrrolidinone (NMP), N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), chloroform, tetrahydrofuran, m-cresol and so on. The ALPI films had an UV-Vis cut-off at 320 nm and a transmittance of higher than 80% in the visible region. In addition, the ALPIs showed thermal decomposition temperatures (T-d) of about 450degreesC, which was nearly 100degreesC lower than that of the ARPIs.
文摘A new aromatic asymmetrical ether diamine, 1,4-bis（3＇,4’-diaminophenoxy）benzene 3 was synthesized in three steps, using hydroquinone as starting material. A new aromatic polyimide containing asymmetrical diaryl ether segments was prepared from the resulting diamine with 4,4＇-oxydiphthalic anhydride （ODPA） via a conventional two-step thermal or chemical imidization method. The resulting polyimide exhibits high thermal resistance, excellent solubility, film-forming capability, high mechanical strength and modulus.
基金support from the Research Foundation of the State Key Laboratory of Applied Organic Chemistry
文摘A new kind of aromatic diamine monomer containing pyridine unit,2,6-bis[4-(4-aminophenoxy)phenoxy]pyridine(BAPP),was synthesized in three steps,using hydroquinone as starting material.A novel pyridine-containing polyimide was prepared from the resulting diamine BAPP with 4,4 -oxydiphthalic anhydride(ODPA) via a conventional two-step thermal imidization method.The resulting polyimide exhibits excellent solubility,film-forming capability and high thermal resistance.
文摘A novel class of aromatic polyimide-silicone segmented copolymer was synthesized with α, ω-bis (γ-aminopropyl) polydimethyldiphenylsiloxane (APMPS) as a silicone segment precursor, from which the segmented polyamic acid-b-silicone intermediate could be prepared simply with DMF as solvent. The segmented copolymer displays microphase separation and exhibits improved antithrombogenicity, which depends mainly upon both the content level and the DP of the silicone segment. Thermal stability and mechanical property of the copolymer are between that of the aromatic polyimide and the silicone, and also relate to both the content level and the DP of the silicone segment.
