Structural effect of monomer type on properties of copolyimides and copolyimide-silica hybrid materials
In this work, the effect of two different diamine monomers, containing phosphine oxide, on thermal, mechanical and morphological properties of copolyimides and their hybrid materials was investigated. Gas separation properties of the synthesized copolyimides were also analysed. Two differen...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Serbian Chemical Society
2015-01-01
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| Series: | Journal of the Serbian Chemical Society |
| Subjects: | |
| Online Access: | http://www.doiserbia.nb.rs/img/doi/0352-5139/2015/0352-51391500029K.pdf |
| Summary: | In this work, the effect of two different diamine monomers, containing
phosphine oxide, on thermal, mechanical and morphological properties of
copolyimides and their hybrid materials was investigated. Gas separation
properties of the synthesized copolyimides were also analysed. Two different
diamine monomers with phosphine oxide were bis(3-aminophenyl) phenylphosphine
oxide (BAPPO) and bis(3-aminophenoxy-4-phenyl) phenylphosphine oxide
(m-BAPPO). In the synthesis of copolyimides 3,3’-diamino-diphenyl sulfone
(DDS) was also used as the diamine, as well as
2,2’-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride (6FDA).
Copolyimide films were prepared by thermal imidization. Hybrid materials
containing 5 % SiO2 were synthesised further by sol-gel technique. The
Fourier-transform infrared spectroscopy (FTIR), Nuclear magnetic resonance
spectroscopy (NMR) confirmed the expected structure. Dynamic mechanical
analysis (DMA) demonstrated that m-BAPPO based copolyimides had lower glass
transition temperatures (Tg) than BAPPO based copolyimides. m-BAPPO
containing copolyimide without silica shifted the thermal decomposition
temperature to a higher value. The moduli and strength values of BAPPO
diamine containing copolyimide and its hybrid were higher than those of
m-BAPPO containing materials. The contact angle measurements showed the
hydrophobicity. Scanning electron microscope (SEM) analysis exhibited the
silica particles dispersion in the copolyimides. These copolyimides may be
used in the coating industry. The CO2 permeability and the permselectivity
were the highest among the other values in this study, when m-BAPPO
containing copolyimide in the absence of silica was used. The gas
permeabilities obtained from this work were in this decreasing order: PCO2 >
PO2 > PN2. |
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| ISSN: | 0352-5139 1820-7421 |