Synthesis of anew siloxane-containing diamine and related polyimide

A novel siloxane-containing diamine, bis[4-(p-aminophenoxy)phenoxy]dimethylsilane (APPMS), was successfully synthesized in three steps using hydroquinone as starting material, which was reacted with 4,4'-oxydiphthalic anhydride (ODPA) via a conventional two-step thermal or chemical imidization method to produce a new siloxane-containing polyimide. The resulting polyimide exhibited excellent solubility, and film-forming capability.     

Synthesis and characterization of novel polyimides based on thiazole-containing diamine

A new kind of aromatic diamine monomer containing thiazole unit,2-amino-5-(4-aminophenyl)-thiazole (AAPT),was synthesized in three steps,starting from 4-nitroacetophenone.A novel thiazole-containing polyimide was prepared via the polycondensation of AAPT with 6FDA by one-step method.The resulting polyimide exhibits excellent solubility,film-forming capability and high thermal resistance.     

Synthesis and characterization of novel polyimides derived from 4-phenyl-2, 6-bis [3-(4-aminophenoxy)-phenyl]-pyridine diamine and aromatic dianhydrides

A new kind of pyridine-containing aromatic diamine monomer, 4-phenyl-2, 6-bis [3-(4-aminophenoxy)phenyl]-pyridine(m-PAPP),was synthesized by a modified Chichibabin reaction of benzaldehyde and a substituted acetophenone, 3-(4-nitrophenoxy)-acetophenone(m-NPAP), and a reduction of the resulting dinitro compound 4-phenyl-2, 6-bis[3-(4-nitrophenoxy)phenyl]-pyridine (m-PNPP) with Pd/C and hydrazine monohydrate, successively. A series of novel aromatic polyimides were prepared from the diamine with various aromatic dianhydrides via a conventional two-step thermal or chemical imidization method. The inherent viscosities of the resulting poly (amic acid) precursors were 1.37-1.56 dL/g, and these polymers could be cast and thermally converted into transparent, flexible, and tough polyimide films. The polyimides displayed higher solubility in polar solvents such as NMP, DMSO and m-cresol. The glass transition temperatures of these polymers were recorded at 180-264 °C. All of these novel polyimides held 10% weight loss at the temperature above 430 °C and left more than 50% residue even at 800 °C in air, as well as have outstanding mechanical properties with the tensile strengths of 91.6-114.1 MPa and elongations at breakage of 10.1-15.7%. Wide-angle X-ray diffraction measurements revealed that these polyimides were predominantly amorphous.     

Synthesis and characterization of novel polyimides derived from pyridine-bridged aromatic dianhydride and various diamines

A new kind of pyridine-bridged aromatic dianhydride monomer, 4-phenyl-2,6-bis[4-(3,4-dicarboxyphenoxy)phenyl]-pyridine dianhydride (PPDA), was successfully synthesized by modified Chichibabin reaction of benzaldehyde and substituted acetophenone, 4-(3,4-dicyanophenoxy)-acetophenone (DCAP), followed by acidic hydrolysis of the intermediate tetranitrile and cyclodehydration of the resulting tetraacid. The pyridine-bridged aromatic dianhydride was employed to synthesized a series of new pyridine-containing polyimides by polycondensation with various aromatic diamines in N-methyl-2-pyrrolidone (NMP) via the conventional two-step method, i.e. ring-opening polycondensation forming the poly(amic acid)s and further thermal or chemical imidization forming polyimides. The inherent viscosities of the resulting polyimides were in the range of 0.49-0.63 dL/g, and most of them were soluble in aprotic amide solvents and cresols, such as N,N-dimethylacetamide (DMAc), NMP, and m-cresol, etc. Meanwhile, strong and flexible polyimide films were obtained, which have good thermal stability with the glass transition temperatures (T_g) of 223-256 °C, the temperature at 5% weight loss of 523-569 °C, and the residue at 700 °C of 52.1-62.7% in nitrogen, as well as have outstanding mechanical properties with the tensile strengths of 70.7-97.6 MPa and elongations at breakage of 7.9-9.7%. Wide-angle X-ray diffraction measurements revealed that these polyimides were predominantly amorphous.     

Synthesis of a new aromatic diacid containing pyridine ring and related polybenzimidazole

<正>A new aromatic diacid monomer containing pyridine unit,4-phenyl-2,6-bis[4-(4-carboxyphenoxy) phenyl]pyridine 3,was successfully synthesized in three steps,starting from 4-hydroxyacetophenone.The corresponding pyridine-containing polybenzimidazole was prepared via polycondensation of 3 with tetraaminodiphenyl ether(TADE) in poly(phosphoric acid)(PPA).The resulting polybenzimidazole exhibits excellent solubility,good thermal stabilities and high thermal resistance.     

Characterizations and thermal stability of soluble polyimide derived from novel unsymmetrical diamine monomers

Two kinds of novel aromatic, unsymmetrical diamines with ether-ketone group, 3-amino-4′-(4-amino-2-trifluoromethylphenoxy)-benzophenone and 3-amino-4′-(4-aminophenoxy)-benzophenone, was successfully synthesized by two different synthetical routes and polymerized with various aromatic tetracarboxylic acid dianhydrides, including 4,4′-oxydiphthalic anhydride, 3,3′,4,4′-benzophenone tetracarboxylic dianhydride, and 2,2′-bis(3,4-dicarboxyphenyl)-hexafluoropropane dianhydride, via a conventional two-step thermal or chemical imidization method to produce a series of fluorinated polyimides. The polyimides were characterized with solubility tests, viscosity measurements, mechanical properties tests, IR-FT, and thermogravimetric analysis. The polyimides had inherent viscosities of 0.54-0.77 dL/g and were easily dissolved in both polar, aprotic solvents and common, low-boiling-point solvents. The resulting strong and flexible polyimide films exhibited excellent thermal stability, with decomposition temperatures (at 10% weight loss) above 573 °C and glass-transition temperatures in the range of 222-251 °C. Moreover, the polymer films showed outstanding mechanical properties, with tensile strengths of 86.5-121.6 MPa, elongations at break of 9-16%, and initial moduli of 1.26-1.97 GPa. These outstanding combined features ensure that the polymers are desirable candidate materials for advanced applications.     

Novel organosoluble polyimide based on an asymmetric bis(ether amine): 3, 4′-Bis(4-aminophenoxy)-benzophenone

A new kind of asymmetrical ether diamine,3,4’-bis（4-aminophenoxy）benzophenone（BABP）,was synthesized from the nucleophilic substitution reaction of 4-chloronitrobenzene and 3,4’-dihydroxybenzophenone in the presence of potassium carbonate,followed by catalytic reduction with SnCl₂-6H₂O and concentrated hydrochloric acid.The prepared diamine was employed in the preparation of a novel polyimide containing asymmetrical diaryl ether segments via the polycondensation of it with BTDA by a two-step method.The resulting polyimide exhibits excellent solubility,film-forming capability and high thermal resistance.     

Synthesis of a new aromatic dianhydride monomer and related polyimide

A novel aromatic dianhydride monomer,3,3′-oxybis[(3,4-dicarboxyphenoxy)phenol]dianhydride,was successfully synthe- sized in three steps using 3,3′-oxybis(phenol)as starting material,which was reacted with 4,4′-oxydianiline(ODA)via a conventional thermal or chemical imidization method to produce a new polyimide.The resulting polyimide exhibited excellent solubility,and film-forming capability.     

The transport properties of polyimide isomers containing hexafluoroisopropylidene in the diamine residue

The effect of modification of the central moiety of the dianhydride residue and isomerism on the gas transport and physical properties were compared for six polyimides containing the hexafluoroisopropylidene group in the diamine residue. Substitution of bulkier groups within the dianhydride residue resulted in disruption of chain packing and slight increases in resistance to chain motions which led to an increase in permeability with little loss in selectivity. The permeabilities and diffusivities in the meta connected polyimide isomers were considerably lower than in the para connected polyimide isomers. Similarly, the permselectivities in the meta connected isomers were consistently higher than in the para connected isomers. These lower permeabilities and higher permselectivities were a result of the more dense packing and a significant suppression of small scale motions in the meta connected isomers. The suppression of segmental mobility in the meta connected isomers was indicated by an increase in the sub Tg transition temperatures in these materials relative to the para connected isomers. The differences in transport properties for these polyimides were attributed to contributions by several factors, including: (1) total free volume (2) distribution of free volume (3) intersegmental resistance to chain motions, and (4) intrasegmental resistance to chain motions. © 1994 John Wiley & Sons, Inc.     

Synthesis and characterization of two novel pyridine-containing framework gallium ethylenediphosphonates

Two novel gallium diphosphonates, (C₅H₅N)Ga₃F(O₃PC₂H₄PO₃)₂ (I) (triclinic, P-1, a=8.2880(12) Å, b=11.7197(16) Å, c=11.7601(17) Å, α=71.589(3)°, β=70.577(3)°, γ=77.313(3)°, V=1013.7(2) Å³, Z=2, R₁=0.0352, wR₂=0.0980) and (C₅H₅NH)₂[Ga₄F₂(O₃PC₂H₄PO₃)₃] (II) (triclinic, P-1, a=8.670(4) Å, b=9.742(3) Å, c=10.406(2) Å, α=81.44(3)°, β=65.83(5)°, γ=67.16(3)°, V=739.0(4) Å³, Z=2, R₁=0.0600, wR₂=0.1495) have been synthesised by solvothermal methods in the presence of pyridine and their structures determined using single-crystal X-ray diffraction data. Both compounds I and II are composed of various Ga-centered polyhedra and ethylenediphosphonate groups that link together to form framework materials with one- and two-dimensional channel systems, respectively. The two structures are formed in the presence of structure-directing pyridine molecules that are directly bound to some of the Ga atoms in I, and are protonated as pyridinium cations in II. Compounds I has a charge-neutral framework, while compound II has an anionic framework. Both materials provide rare examples of organically structure-directed framework metal diphosphonate materials.     

Novel polyimides obtained from a new aromatic diamine (BAPO) containing pyridine and 1,3,4‐oxadiazole moieties for removal of Co(II) and Ni(II) ions

Novel, thermally stable polyimides (PIs) containing a 1,3,4‐oxadiazole and pyridine moieties based on a new aromatic diamine 2,5‐bis‐(aminopyridine‐2‐yl)‐1,3,4‐oxadiazole, BAPO, were synthesized. The prepared polymers were soluble in dimethysulfoxide (DMSO) and concentrated sulfuric acid at room temperature as well as in polar and aprotic solvents, such as, N‐methylpyrrolidone (NMP) and N,N‐dimethylacetamide (DMAc) at elevated temperature. Thermal behaviors of the PIs were studied by thermogravimetric analysis/dynamic thermal analysis (TGA‐DTA) and differential scanning calorimetry (DSC). The inherent viscosities of the PI solutions were in the range of 0.38–0.61 dl/g (in DMSO with a concentration of 0.125 g/dl at 25 ± 0.5°C). The removal of Co(II) and Ni(II) ions from aqueous solutions was performed using polymer 6, which was obtained from BAPO and 3,3′,4,4′‐benzophenonetetracarboxylic dianhydride (BTDA). The maximum adsorption capacity was observed for Co(II) ion at pH = 7.0 (110.4 mg g^?1, 1.87 mmol g^?1). Copyright © 2015 John Wiley & Sons, Ltd.     

Synthesis of a New Asymmetrical Ether Diamine with Aromatic Structure and Related Polyimide

Aromatic polyimides are widely used in the microelectronic industry as electrical insulators, passivation layers, and liquid-crystal alignment layers, because of their excellent mechanical, electrical, chemical, and thermal properties1,2. Despite their ou…     

Synthesis of thermotropic liquid crystal polyimide and its properties

Thermotropic liquid crystal polyimide which has neither an ester linkage nor a carbonate linkage was prepared by the polymerization of 1,2,4,5-benzenetetracarboxylic dianhydride (PMDA) and 1,3-bis[4-(4′-aminophenoxy)cumyl)]benzene (BACB). This polyimide shows the liquid crystal phase at 549-593 K. Mixing this liquid crystal polyimide or copolymerizing BACB decreases the melt viscosity of the thermoplastic polyimide (Aurum). © 1994 John Wiley & Sons, Inc.     

芳香族二胺聚合物修饰电极对痕量重金属离子的络合与探测

电合成的芳香族二胺聚合物链中存在大量自由氨基和亚氨基,由其自组装而成的修饰电极可以和重金属离子如Ag^ 、Pb^2 、Hg^2 、Cu^2 形成络合物,进而实现对痕量重金属离子的富集与探测。该修饰电极对Ag^ 和Pb^2 的探测呈现极好的线性关系,线性相关系数在0．998左右,探测极限分别可低达10mmol/L和0．15μmol/L。电极上修饰聚合物膜厚度、富集时间、pH、共存金属离子等因素都会影响重金属的富集和探测。芳香族二胺聚合物修饰电极在痕量金属离子的探测、污水处理乃至重金属离子传感等方面都显示出极大的应用潜力。     

Synthesis and characterization of fluorinated polyimides derived from novel unsymmetrical diamines

Two kinds of aromatic, unsymmetrical diamines with ether-ketone group, 3-amino-4′-(4-amino-2-trifluoromethylphenoxy)-benzophenone and 4-amino-4′-(4-amino-2-trifluoromethylphenoxy)-benzophenone, were successfully synthesized with two different synthetic routes. Then, they were polymerized with 4,4′-oxydiphthalic anhydride, 3,3′,4,4′-benzophenone tetracarboxylic dianhydride, and 2,2′-bis(3,4-dicarboxyphenyl)-hexafluoropropane dianhydride to form a series of fluorinated polyimides via a conventional two-step thermal or chemical imidization method. The resulting polyimides were characterized by measuring their solubility, viscosity, mechanical properties, IR-FT, and thermal analysis. The results showed that the polyimides had inherent viscosities of 0.48-0.68 dl/g and were easily dissolved in bipolarity solvents and common, low-boiling point solvents. Meanwhile, the resulting strong and flexible polyimide films exhibited excellent thermal stability, e.g., decomposition temperatures (at 10% weight loss) are above 575 °C and glass-transition temperatures in the range of 218-242 °C. The polymer films also showed outstanding mechanical properties, such as tensile strengths of 86.5-132.8 MPa, elongations at break of 8-14%, and initial moduli of 1.32-1.97 GPa. These outstanding combined features ensure that the polymers are desirable candidate materials for advanced applications.     

3,3'-二氨基查尔酮的合成

3;3'-二氨基查尔酮的合成;光敏性二胺;查尔酮;聚酰亚胺;合成     

Synthesis of novel hyperbranched polyimide for liquid crystal alignment

A novel hyperbranched polyimide (HPPI) was synthesized from a new four‐functional amine and 1,2,3,4‐cyclobutanetetracarboxylic dianhydride. The polyimide with hyperbranched structure exhibited excellent alignment for nematic liquid crystal (LC) compared with traditional linear polyimides. The solution viscosities of the poly(amic acids) (PAAs) and the surface morphology of PI films were investigated using an Ubbelhode‐type viscometer and atomic force microscopy, respectively. The viscosities of the hyperbranched PAAs were much lower than that of the linear PAA solution at any monomer ratio (amine:dianhydride). Pretilt angles of LCs above 2.8° were achieved with HPPI.     

含三苯胺结构癈聚酰亚胺的合成及光电转换性能研究

通过缩聚方法合成了主链含三苯胺结构的苝聚酰亚胺，将其负载在纳米二氧化钛膜上，光电转换性能测定结果表明，含三苯胺结构苝聚酰亚胺具有良好的光电转换特性，其光电流比不含三苯胺结构的苝聚酰亚胺大11倍。     

Electrochemical behavior of a new electroactive polyimide derived from aniline trimer

The electrochemical behavior of a soluble polyimide (Tani-polyimide) derived from an aniline trimer was investigated. Similar to processes observed in polyaniline, two typical redox processes involving protonation and ion insertion were observed. Due to the presence of an isolated, short quinonediimine or N,N′-diphenyl-p-phenylenediamine segment, Tani-polyimide displayed an electroactivity at higher potentials and did not undergo an electrochemical degradation reaction. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 4295–4301, 1999     

Molecular dynamics study of the persistence lengths of a new class of polyimide fibers

The transformation matrix method and the concept of virtual bonds has been applied to the study of the persistence lengths of two recently developed polyimide fibers, PMDA-PFMB, synthesized from pyromellitic dianhydride (PMDA) and 2,2′-bis(trifluoromethyl)-4,4′-diaminobiphenyl (PFMB), and BPDA-PFMB, synthesized from 3,3′,4,4′-biphenyltetracarboxylic dianhydride (BPDA) and PFMB. The elements of the averaged transformation matrices are obtained from a molecular dynamics trajectory of 1 ns and from a consideration of the symmetry of the torsion potential energy function for selected bonds. The persistence length is found to be ∼ 496 AÅ for PMDA-PFMB and ∼ 66 AÅ for BPDA-PFMB. The large persistence length of PMDA-PFMB, comparable to that of the rodlike polymer poly(benzobisoxazole) (PBO), is caused by the colinearity of the virtual bonds in the chain and the stiffness of the bond angles. The inclusion of the electrostatic interactions does not seem to affect the result significantly, although a very slight decrease (∼ 5%) of the persistence length was detected. The effect of substitution of methyl groups for the trifluoromethyl groups in these polyimide fibers is also studied, with an increase of ∼ 14% in the persistence length of PMDA-PFMB and ∼ 1.4% in the persistence length of BPDA-PFMB. Since a good solvent that would be appropriate for use in a light scattering measurement has not been found for either of these polyimide fibers, the theoretical estimates of the persistence length cannot be compared with experiment. © 1996 John Wiley & Sons, Inc.