Synthesis and characterization of novel aromatic polyimides from 4,4-bis(p-aminophenoxymethyl)- 1-cyclohexene
โ Scribed by Havva Yagci; Cher Ostrowski; Lon J. Mathias
- Publisher
- John Wiley and Sons
- Year
- 1999
- Tongue
- English
- Weight
- 164 KB
- Volume
- 37
- Category
- Article
- ISSN
- 0887-624X
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โฆ Synopsis
A novel diamine, 4,4-bis(p-aminophenoxymethyl)-1-cyclohexene (CHEDA), was synthesized from 4,4-bis(hydroxymethyl)-1-cyclohexene and p-chloronitrobenzene by nucleophilic aromatic substitution and subsequent catalytic reduction of the intermediate dinitro compound. A series of aromatic polyimides were prepared from CHEDA and commercial dianhydrides with varying flexibility and electronic character in twostep direct polycondensation reactions. High molecular weight polyimides with intrinsic viscosities between 0.57 and 10.2 dL/g were obtained. Most of these polyimides, excluding those from PMDA and BPDA, were soluble in polar aprotic solvents such as NMP and DMAc, and many were also soluble in CHCl 3 and THF. DSC analysis revealed glass transitions in the range of 190 to 250ยฐC. No significant weight losses occurred below 450ยฐC in nitrogen and 350ยฐC in air. Bromination and epoxidation of cyclohexene double bond in CHDEA-6FDA (3e) were investigated as examples of possible polymer modifications. Qualitative epoxidation and selective bromination of the double bond were demonstated.
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