Mesophase behaviour of 1:1 mixtures of 4-n-alkoxyphenylazo benzoic acids bearing terminal alkoxy groups of different chain lengths. Issue 9 (14th July 2016)

• Record Type: Journal Article
• Authors: Ahmed, H.A.; Naoum, M.M.; Saad, G.R.
• Is Part Of: Liquid crystals. Volume 43:Issue 9(2016)
• Page Start: 1259
• Page End: 1267
• Publication Date: 2016-07-14
• Subjects: 4-n-alkoxyphenylazo benzoic acids -- 4-n-alkoxy benzoic acids -- binary mixtures -- phase transitions; Liquid crystals -- Periodicals; 548.905
• DOI: 10.1080/02678292.2016.1166528
• Languages: English
• ISSNs: 0267-8292

Abstract

ABSTRACT: The thermal and mesophase behaviour of all possible 1:1 mixtures (I n/ I m ) formed from any two homologues of 4- n -alkoxyphenylazo benzoic acids bearing different alkoxy chain lengths ( n and m vary between 6 and 16 carbons), were investigated by differential scanning calorimetry (DSC) and phases identified by polarised light microscopy (PLM). Phase transitions were investigated as a function of the average alkoxy chain length ( = ( n + m )/2) of the mixed acids. A comparison, made between the present series and previously investigated simpler analogues, 4- n -alkoxy benzoic acids, revealed that increasing the length of the mesogenic core increased the stabilities of both the smectic C and nematic phases. GRAPHICAL ABSTRACT: