Synthesis and properties of polyimide–clay hybrid
01 Sep 1993-Journal of Polymer Science Part A (John Wiley & Sons, Inc.)-Vol. 31, Iss: 10, pp 2493-2498
TL;DR: A polyimide hybrid with montmorillonite clay mineral has been synthesized from a dimethylacetamide (DMAC) solution of poly(amic acid) and a DMAC dispersion of montmoroniite intercalated with an ammonium salt of dodecylamine as mentioned in this paper.
Abstract: A polyimide hybrid with montmorillonite clay mineral has been synthesized from a dimethylacetamide (DMAC) solution of poly(amic acid) and a DMAC dispersion of montmorillonite intercalated with an ammonium salt of dodecylamine. Montmorillonite consists of stacked silicate sheets about 2000 A in length, 10 A in thickness. In this hybrid, montmorillonite is dispersed homogeneously into the polyimide matrix and oriented parallel to the film surface. Thanks to this special structure, this hybrid showed excellent gas barrier properties. Only 2 wt % addition of montmorillonite brought permeability coefficients of various gases to values less than half of those of ordinary polyimide. Furthermore, this hybrid had low thermal expansion coefficient. © 1993 John Wiley & Sons, Inc.
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TL;DR: A review of the academic and industrial aspects of the preparation, characterization, materials properties, crystallization behavior, melt rheology, and processing of polymer/layered silicate nanocomposites is given in this article.
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Cites background or methods from "Synthesis and properties of polyimi..."
...[11,255] for the preparation of polyimide/MMT nanocomposites from a dimethylacetamide (DMAC) solution of poly(amic acid) and a DMAC dispersion of MMT modified with dodecylammonium cations....
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...[11] Yano K, Usuki A, Okada A, Kurauchi T, Kamigaito O....
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...PSF/organoclay nanocomposites were obtained by mixing the desired amount of the organoclay with PSF in DMAC at 80 8C for 24 h. WAXD analyses and TEM observations established exfoliation of the organoclay in the nanocomposites....
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...Biomedical polyurethane urea (PUU)/MMT (MMT modified with dimethylditallowammonium cation) nanocomposites were prepared by adding OMLS suspended in toluene drop-wise to the solution of PUU in N,N-dimethylacetamide (DMAC) [8]....
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...This technique was successfully used by Yano et al. [11,255] for the preparation of polyimide/MMT nanocomposites from a dimethylacetamide (DMAC) solution of poly(amic acid) and a DMAC dispersion of MMT modified with dodecylammonium cations....
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