光敏性聚酰亚胺的合成及其在液晶光致取向中的运用

通过羟基聚酰亚胺与肉桂酸的接枝反应合成了具有光敏性的聚酰亚胺,并且通过红外,核磁确定了光敏性聚酰亚胺的结构,将合成的聚酰亚胺作为液晶取向层用在液晶显示器件中,证明其有良好的热稳定性。     

Synthesis of polyimides and segmented block copolyimides by transimidization

The transimidization reaction has been successfully utilized to prepare a series of segmented block copolyimides. The synthesis and polymerization of an AX‐type amino imide monomer containing the tetrahydro[5]helicene unit were accomplished. The AX‐type amino imide monomer is stable during isolation and purification, owing to its inert X (e.g., N‐pyridyl) group, but yet readily underwent a self‐transimidization reaction and produced polyimide. Because of the presence of two reactive ends, such an AX‐type polyimide could be incorporated into a series of block copolyimides by reaction with commercially available dianhydrides and diamines. All the copolymers showed two distinct glass‐transition temperatures, typically around 250 and 430 °C. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 3991–3996, 2000     

Miscibility of polyimide with polymeric primer and its influence on adhesion of polyimide to the primed copper metal: Effect of precursor origin

Poly(amic acid) (PAA) and poly(amic diethyl ester) (PAE) precursors of poly(4,4′-oxydiphenylene biphenyltetracarboximide) (BPDA-ODA PI) were synthesized. Miscibility behaviors of these precursors with poly(arylene ether benzimidazole) (PAEBI), which is a good adhesion primer for copper metal, were investigated in N-methyl-2-pyrrolidone (NMP) as well as the condensed state and the imidized state. For the PAA/PAEBI blend over the whole range of compositions, no cloud point was measured either in the NMP solution, the condensed state, or the imidized state. Furthermore, no aggregation of PI chains in the blend films was detected by X-ray diffraction. These results indicate that the PAA and PAEBI are completely miscible at the molecular level, consequently leading to the miscible PI/PAEBI blend. This miscibility might result from the strong interaction via the complex formation of imidazole groups of the PAEBI and carboxylic acid groups of the PAA precursor. In contrast, the miscibility of PAE/PAEBI blend in NMP was limited up to a concentration of 13.5–36.3 wt %, leading to a phase separation in the soft-baked and imidized blend. The blend films rich with one component were optically transparent, which might be due to the phase-separated domains much smaller than 1 μm. The immiscibility might result from the relatively weak interactions of imidazole groups of PAEBI with both the ester and amide linkages in the PAE precursor. The difference in the miscibilities of PAEBI with the PAA and PAE precursors was reflected in the adhesion of PI/PAEBI/copper joints: higher miscibility gave higher adhesion strength. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 2806–2814, 1999     

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     

Synthesis and imidization of poly(amic methyl ester)s

The synthesis and characterization of a series of poly(amic methyl ester)s from five aromatic dianhydrides and a diamine, 4,4′-oxydianiline (ODA), are described. These poly(amic ester)s are obtained by the low-temperature polycondensation from dianhydrides derived diesterdiacyl chlorides and ODA in DMAc solution with the inherent viscosities in the 0.5–0.9 dL/g range. These precursors are readily soluble in aprotic solvents. A detailed thermal study of the imidization process is presented, based on dynamic and isothermal TGA measurements, FTIR spectroscopy, and dynamic mechanical analysis. © 1997 John Wiley & Sons, Inc.     

Preparation and characterization of polyimide alternating copolymers incorporating N,N′-bis-(4-anilino)-1,2,4,5-benzene bis(dicarboximide)

N,N′-Di-(4-anilino)-1,2,4,5-benzene bis(dicarboximide) was prepared in a three-step synthesis and purified by heating the resulting solid to 200°C. Condensation of the diamino-diimide with several dianhydrides (BPDA, BTDA, and 6-FDA) yielded polyamic acid-imides that could be either thermally or chemically cured to the corresponding alternating copolyimides. Imidization of the polyamic acid-imide to the final polyimide was monitored by FTIR for samples coated on silicon wafers before being thermally cured. Polyimides prepared by chemical imidization were found by thermogravimetric analysis to be stable to temperatures of 600°C. © 1997 John Wiley & Sons, Inc.     

Preparation and absorption spectrum studies of aromatic and alicyclic poly(amide acid) ammonium salts in water and DMF and in films

A series of ammonium salts of poly(amide acid)s (PAS) were prepared from various poly(amide acid)s (PAA) with tertiary amines. The solubility of poly(amide acid) ammonium salts prepared from PAA(PMDA/ODA) in water is related to the ion concentration of tertiary amines. In order to elucidate the influence of the chemical structures of poly(amide acid)s and poly(amide acid) ammonium salts on their absorption spectra, pyromellitic dianhydride (PMDA), 3,3′,4,4 ′-biphenyltetracarboxylic dianhydride (BPDA), and 3,3′,4,4 ′-benzophenonetetracarboxylic dianhydride (BTDA) were chosen to react with p-phenylenediamine (PDA) and (4,4′-diaminodicyclohexyl)methane (DCHM) to give three kinds of aromatic PAAs and three kinds of alicyclic PAAs. The corresponding PASs were prepared by the reaction of PAAs with triethanolamine (TEA). Their ultraviolet–visible (UV–vis) absorption spectra were investigated compared to those of model compounds. A transparent film without absorption above 320 nm was obtained for PAS(PMDA/DCHM). The difference in absorption spectra of PAS(PMDA/PDA) from that of PAS(PMDA/DCHM) can be related to the existence of intra- and intermolecular charge transfer (CT) for PAS(PMDA/PDA). The absorption spectra of PASs with PDA in films are red shifted compared to those of corresponding PAAs in films, while the absorption spectra of PASs in water are blue shifted compared to those of corresponding PAAs in DMF. No differences in the absorption spectra of PAAs and PASs were found in DMF/H₂O (9/1) mixed solvent. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1329–1340, 1998     

聚酰亚胺LB膜研究 Ⅱ.聚酰胺酸N,N-二甲基十八铵盐LB膜的表征和热分解性能

聚酰胺酸Ｎ,Ｎ－二甲基十八铵盐ＬＢ膜具有严格排列的周期结构,其亚胺化可以在比聚酰胺酸更为温和的条件下进行。测定了沉积在单晶硅片上的聚酰亚胺涂膜的热分解性能。于真空和高温下聚酰亚胺ＬＢ膜会热解并与基片硅反应而生成规则结构的ＳｉＣ准单晶膜。