Two‐step thermal conversion from poly(amic acid) to polybenzoxazole via polyimide: Their thermal and mechanical properties

Chang, Jin‐Hae; Park, Kwang Min; Lee, Soo‐Min; Oh, Jae Buem

doi:10.1002/1099-0488(20001001)38:19<2537::aid-polb50>3.3.co;2-m

Cited by 19 publications

(28 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…If the polymers were preheated isothermally for 1 h at 480 °C under vacuum, then the thermal decomposition temperatures (the second set of T d, 5% values) would be much higher than the first set. This was attributed to the thermal conversion of PI to a thermal stable PBO that possessed a higher T d 19, 20. Also, as illustrated in Fig.…”

Section: Resultsmentioning

confidence: 89%

See 1 more Smart Citation

2,6‐Diamino‐4‐phenylphenol (DAPP) copolymerized polyimides: synthesis and characterization

Chen

Tsai

Tsay

2005

Polymer International

View full text Add to dashboard Cite

Novel soluble copolyimides containing phenyl and hydroxyl pendant groups were synthesized from pyromellitic dianhydride (PMDA) and two diamines, 2,6-diamino-4-phenylphenol (DAPP) and 4,4 -oxydianiline (ODA), in various ratios via thermal imidization. The structures and physical properties of the copolyimides were characterized by FTIR, elemental analysis, DSC, dynamic mechanical analysis (DMA), TGA, a universal testing machine for stress-strain behaviour, and a dielectric analyzer to study the effect of DAPP on the physical properties of the modified polymers. Copolyimides containing more than 40 mol% DAPP were soluble in hot N-methyl-2-pyrrolidone (NMP), dimethylacetamide (DMAc) and dimethylformamide (DMF), and possessed a high glass transition temperature (358 • C) and a high modulus (3.9 GPa). Introduction of the diamine DAPP could also reduce the dielectric constant. A segment of imide linkages could convert to benzoxazole linkages by decarboxylation at temperatures higher than 420 • C under vacuum. Although the heat-treated polybenzoxazoles (PBOs) exhibited many good properties, they were found to be too rigid and brittle to be processable for microelectronic applications.

show abstract

Section: Resultsmentioning

confidence: 89%

“…The hydroxyl‐containing polyimide can undergo rearrangement to an aromatic PBO via in situ thermal conversion 19, 20. Figure 4 shows the FTIR spectra of CPI 4 at various elevated temperatures under vacuum.…”

Section: Resultsmentioning

confidence: 99%

2,6‐Diamino‐4‐phenylphenol (DAPP) copolymerized polyimides: synthesis and characterization

Chen

Tsai

Tsay

2005

Polymer International

View full text Add to dashboard Cite

show abstract

“…S5 †). The rst weight loss was observed around 368 up to 426 C and it was ascribed to the elimination of the methoxy pendant groups present in the TMBA, which could be converted to benzoxazole rings by thermal rearrangement; [22][23][24] meanwhile the second weight loss in the range of 496 to 592 C was ascribed to the polymer backbone degradation. Moreover, the char yield at 800 C was found in the range of 53 to 56 wt%.…”

Section: Thermal Propertiesmentioning

confidence: 99%

Synthesis and characterization of poly(amide-imide)s derived from a new ortho-functional unsymmetrical dicarboxylic acid

et al. 2018

View full text Add to dashboard Cite

show abstract

“…In 2007, Park et al extended this idea to gas separation membranes [4]. Since this initial report, much research has focused on this interesting family of materials [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21].…”

Section: Introductionmentioning

confidence: 99%

Gas permeation properties of thermally rearranged (TR) isomers and their aromatic polyimide precursors

Liu

Borjigin

Paul

et al. 2016

Journal of Membrane Science

View full text Add to dashboard Cite

This study explores the influence of meta/para and ortho-position functional group structures on gas transport properties of two isomeric polyimides and their thermally rearranged (TR) polymers. The diamine isomers, 3,3'-dihydroxy-4,4'-diamino-biphenyl (p-HAB) and 4,4'dihydroxybiphenyl-3,3'-diamino-biphenyl (m-HAB), were polymerized with 2,2'-bis-(3,4dicarboxy-phenyl) hexafluoropropane dianhydride (6FDA) to form two aromatic polyimide isomers. These polyimides were also prepared with either hydroxyl or acetate groups at the ortho-positions to the imide ring, and the polyimides were partially converted to the corresponding polybenzoxazoles by thermal treatment at various temperatures and times. Single gas permeabilities of CH4, H2, O2, N2 and CO2 were measured at 35 o C and upstream pressures ranging from 3 atm to 17 atm. Polyacetylimides and their corresponding TR polymers showed higher gas permeability and lower selectivity than polyhydroxyimides and their TR analogs, respectively. The effect of isomerism on gas transport properties was also investigated. Paraconnected polyhydroxyimide had higher fractional free volume, and thus, gas permeability coefficients than meta-connected polyhydroxyimide. Interestingly, in contrast to the meta/para effects previously reported in the literature for linear aromatic polymers, the meta-linked polyacetylimide had higher permeabilities and lower selectivities than its para-linked analog, presumably due to steric hindrance from the acetate groups that may inhibit the rotational mobility of the phenylene units in the para-linked isomer. For TR polymers derived from either polyhydroxyimides or polyacetylimides, para-configured polymers had higher gas permeabilities than meta-configured analogs. Finally, polyimide precursors for TR polymers can be sensitive to synthesis and casting conditions, and this study demonstrates how small variations in synthesis and casting procedure can have a significant effect on physical and gas permeation properties.

show abstract

Two‐step thermal conversion from poly(amic acid) to polybenzoxazole via polyimide: Their thermal and mechanical properties

Cited by 19 publications

References 0 publications

2,6‐Diamino‐4‐phenylphenol (DAPP) copolymerized polyimides: synthesis and characterization

2,6‐Diamino‐4‐phenylphenol (DAPP) copolymerized polyimides: synthesis and characterization

Synthesis and characterization of poly(amide-imide)s derived from a new ortho-functional unsymmetrical dicarboxylic acid

Gas permeation properties of thermally rearranged (TR) isomers and their aromatic polyimide precursors

Contact Info

Product

Resources

About