Comparison between steady state and transient diffusivities of direct dyes in cellulose

✍ Scribed by E. C. Ibe; S. N. Ibe

• Publisher: John Wiley and Sons
• Year: 1986
• Tongue: English
• Weight: 280 KB
• Volume: 37
• Category: Article
• ISSN: 0323-7648
• DOI: 10.1002/actp.1986.010370305

✦ Synopsis

The differences between the diffusivities obtained by rate of sorption and steady state experiments are analysed. Any noticeable difference between steady state and transient diffusivities are attributable to the fact that the diffusion process is concentration dependent. However, the average or apparent diffusivities obtained by the two methods should idc:illy be the same, irrespective of the interaction between the dye and cellulose.

I 'ergleich der irn stationiiren Zustand gemessenen und der transienten Diffusionskoeffizierilen von Direktfarbstoffen in Cellulose I)ie Unters:hiede zwischen den aus der Sorptionsgeschwindigkeit und durch Messungen im stationaren Zustand erhaltenen Diffusionskoeffizienten werden analysiert. Ein merkbarer Unterschied zwischen den stationaren und den trnnsienten Diffusionskoeffizienten ist darauf zuriickzufiihren, dall der Diffusionsprozell konzentrationsabhangig ist. Im Idealfall sollten die nach beiden Methoden erhaltenen mittleren oder scheiiibaren Diffusionskoeffizienten ubereinstiiiimeii, uiiabhangig von einer Wechselwirkung zwischen dem Farbstoff und der Cellulose.

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.Wicrodisperse polyolefine powders. 2. Comm.: Characterization of the phase separation process of concentrated LDPEsolutions by means of cloud point temperature A method is described for determining the phase separation point of highly concentrated LDPE solutions by measuring the cloud point temperature. The relationship between cloud temperature and size of the resulting PE particles obtained in various solvent systems is discussed.

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