A Novel Preparative Method of Microporous Poly(4,4'-oxydiphenylenepyromellitimide) Membranes

Echigo, Yoshiaki; Iwaya, Yoshiaki; Saito, Minoru; Tomioka, Isao

doi:10.1021/ma00123a041

Cited by 23 publications

(14 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To overcome this drawback, Echigo et al reported that porous poly(4,4′-oxydiphenylenepyromellitimide) can be prepared using the dry phase inversion from pyromellitic dianhydride (PMDA) and 4,4-oxidianiline (ODA) [10]. PMDA and ODA were polymerized in tetrahydrofuran (THF)/methanol (MeOH) to form a prepolymer of poly(4,4′-oxydiphenylene pyromellitimic acid (PAA).…”

Section: Introductionmentioning

confidence: 99%

Porous Polyimide Membranes Prepared by Wet Phase Inversion for Use in Low Dielectric Applications

Kim

Jang

Choi

et al. 2013

IJMS

View full text Add to dashboard Cite

A wet phase inversion process of polyamic acid (PAA) allowed fabrication of a porous membrane of polyimide (PI) with the combination of a low dielectric constant (1.7) and reasonable mechanical properties (Tensile strain: 8.04%, toughness: 3.4 MJ/m3, tensile stress: 39.17 MPa, and young modulus: 1.13 GPa), with further thermal imidization process of PAA. PAA was simply synthesized from purified pyromellitic dianhydride (PMDA) and 4,4-oxydianiline (ODA) in two different reaction solvents such as γ-butyrolactone (GBL) and N-methyl-2-pyrrolidinone (NMP), which produce Mw/PDI of 630,000/1.45 and 280,000/2.0, respectively. The porous PAA membrane was fabricated by the wet phase inversion process based on a solvent/non-solvent system via tailored composition between GBL and NMP. The porosity of PI, indicative of a low electric constant, decreased with increasing concentration of GBL, which was caused by sponge-like formation. However, due to interplay between the low electric constant (structural formation) and the mechanical properties, GBL was employed for further exploration, using toluene and acetone vs. DI-water as a coagulation media. Non-solvents influenced determination of the PAA membrane size and porosity. With this approach, insight into the interplay between dielectric properties and mechanical properties will inform a wide range of potential low-k material applications.

show abstract

Section: Introductionmentioning

confidence: 99%

Porous Polyimide Membranes Prepared by Wet Phase Inversion for Use in Low Dielectric Applications

Kim

Jang

Choi

et al. 2013

IJMS

View full text Add to dashboard Cite

show abstract

“…Nanoporous polymers are prepared in various ways: by using blowing agents, [6,7] by utilizing chemically generated blowing agents, [8] inclusion of glass or carbon microspheres, [9] by microwave processing, [10] by phase inversion of cast films [11] and by decomposing the thermally labile domain in a phase separated block or graft copolymer. [12] The latter method [13] had been developed extensively by the IBM group, and they prepared phase separated block copolymers consisting of thermally stable PI or polyphenylquinoxaline and thermally labile blocks (namely poly-(propylene oxide), [14][15][16][17] poly(methyl methacrylate) [18] and poly(a-methyl styrene)) [12] and successfully formed nanopores by the pyrolysis of the labile block.…”

Section: Introductionmentioning

confidence: 99%

Preparation of Nanoporous Polyimide Films from Poly(urethane‐imide) by Thermal Treatment

Krishnan

Cheng

et al. 2003

Macro Materials & Eng

View full text Add to dashboard Cite

Nanoporous polyimide films were prepared in two steps. The first step is the preparation of poly(urethane‐imide) films by casting blend solutions containing various weight percentages of poly(amic acid) and phenol blocked polyurethane prepolymer (from 1,6‐hexamethylene diisocyanate and poly(ethylene glycol)). Three poly(amic acid)s were obtained from biphenyltetracarboxylic dianhydride (or) 2,2‐bis(3,4‐dicarboxyphenyl)hexafluoropropane dianhydride with 1,4‐phenylenediamine (or) 2,5‐dimethyl‐1,4‐phenylenediamine. Poly(urethane‐imide) films were characterized by density and surface energy measurements, AFM, DSC, TMA, mechanical properties and TGA. In the second step, these films were thermally treated above 300 °C to give nanoporous polyimide films. During thermal treatment, less thermally stable urethane domains decomposed, leaving porous polyimide films. The presence of pores was confirmed by scanning electron microscopy (SEM). The dielectric constant of the polyimide film was found to decrease with increasing amounts of urethane content.A nanoporous polyimide film.magnified imageA nanoporous polyimide film.

show abstract

“…1 These monomers were also frequently employed in studies devoted to PI synthesis using THF/MeOH mixed solvent. [3][4][5] Concentrations of solutions of polyimide precursors (PAA) in NMP for commercial and research purposes usually range from 10 to 15 wt%. Echigo 3,4 describes the preparation of a 15 wt% PAA solution based on the above mentioned monomers using THF/MeOH mixtures with composition ratio 4:1 (w/w).…”

Section: Resultsmentioning

confidence: 99%

Preparation of Polyimides by Using Mixtures of Tetrahydrofuran and Methanol and Their Properties

Sysel

Šindelář

Chánová

et al. 2002

Polym J

View full text Add to dashboard Cite

ABSTRACT:Reaction conditions of the preparation of solutions of polyamic acids in the tetrahydrofuran/methanol mixed solvent (THF/MeOH) were studied. The polyamic acids were based on pyromellitic dianhydride and 4, 4 -oxydianiline. Transparent solutions were prepared at 5 wt% and lower concentrations of polyamic acid in the THF/MeOH mixture with component weight ratio ranging from 4:1 to 1:1. The properties of the final polyimide films were compared with those prepared by using N-methyl-2-pyrrolidone as the solvent.KEY WORDS Methanol / Polyamic Acid / Polyimide / Tetrahydrofuran / Aromatic polyimides (PI) exhibit very good mechanical, dielectric and chemical resistance also at elevated temperatures. They are often employed in (micro)electronics, aviation industry and membrane technologies. 1 Polyimides are traditionally synthesized in two steps ( Figure 1). The final product is often prepared by thermal solid-state imidization of a polyimide precursor (polyamic acid (PAA)). 1 The first step -preparation of PAA -comprises the reaction of an aromatic diamine with an aromatic dianhydride in aprotic polar solvents (e.g., N-methyl-2-pyrrolidone (NMP), N, Ndimethylacetamide, N, N-dimethylformamide). These amidic high-boiling solvents however associate with the carboxyl groups of PAA and removing them from polyimide films can be troublesome. 1 Moreover, polyamic acid solutions in these hygroscopic solvents are unstable and their application using the spin-on technique can be thus complicated. 2 From this point of view the preparation of PAA in the tetrahydrofuran/methanol mixed solvent (THF/MeOH) appears to be promising. [3][4][5][6][7][8] However, in our preliminary tests we were unable to reproduce the preparation of 15 wt% solutions of PAA based on pyromellitic dianhydride (PMDA) and 4, 4 -oxydianiline (ODA) in THF/MeOH with component ratio 4:1 (w/w) as described by Echigo et al. 3,4 The reaction conditions of the preparation of PAA solutions (based on PMDA and ODA) in THF/MeOH mixtures and the transformation of the resulting PAA into PI are studied in this work. The properties of final films are compared with those prepared by using NMP as the solvent. The behaviour of the mixed solvent in dependence on its composition has been monitored. EXPERIMENTALPyromellitic dianhydride was dried overnight at 180 • C in vacuum before using. 4, 4 -Oxydianiline (both Aldrich) was used as received. Tetrahydrofuran (Lachema, Czech Republic) was distilled over sodium. Methanol (Penta, Czech Republic) was used without purification. N-Methyl-2-pyrrolidone (Merck) was distilled under vacuum over phosphorus pentoxide and stored under an inert gas.Polyamic acids were prepared in a three-necked flask equipped with a mechanical stirrer, a nitrogen inlet, and a condenser with a drying tube. The diamine (ODA) was dissolved in the solvent (THF/MeOH or NMP). An equimolar amount of the dianhydride (PMDA) was then added and the reaction was allowed to proceed at room temperature for 24 h.A polyamic acid solution in THF/MeOH or NMP was cast onto...

show abstract

A Novel Preparative Method of Microporous Poly(4,4'-oxydiphenylenepyromellitimide) Membranes

Cited by 23 publications

References 0 publications

Porous Polyimide Membranes Prepared by Wet Phase Inversion for Use in Low Dielectric Applications

Porous Polyimide Membranes Prepared by Wet Phase Inversion for Use in Low Dielectric Applications

Preparation of Nanoporous Polyimide Films from Poly(urethane‐imide) by Thermal Treatment

Preparation of Polyimides by Using Mixtures of Tetrahydrofuran and Methanol and Their Properties

Contact Info

Product

Resources

About