Infrared studies of mixed Langmuir–Blodgett monolayers of octadecyldimethylamine oxide and dioctadecyldimethylammonium chloride with arachidic acid and poly(acrylic acid)

• Published in: Surface science Vol. 427; pp. 107 - 110
• Main Authors: Myrzakozha, Diyas A., Hasegawa, Takeshi, Nishijo, Jujiro, Imae, Toyoko, Ozaki, Yukihiro
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Lausanne Elsevier B.V 01-06-1999; Amsterdam Elsevier Science; New York, NY
• Subjects: Carboxylic acid; Condensed matter: structure, mechanical and thermal properties; Exact sciences and technology; Infrared absorption spectroscopy; IRAS; Langmuir-blodgett films; Physics; Solid–gas interfaces; Surface structure, morphology, roughness, and topography; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Vibrations of absorbed molecules; Solid–gas interfaces; IRAS; Surface structure, morphology, roughness, and topography; Carboxylic acid; Infrared absorption spectroscopy; Vibrations of absorbed molecules; Langmuir-Blodgett films; Infrared spectra; Experimental study; Monolayers; Vibrational modes
• ISSN: 0039-6028; 1879-2758
• DOI: 10.1016/S0039-6028(99)00243-5

Infrared reflection–absorption spectra (IRAS) have been measured for monolayers of octadecyldimethylamine oxide (C
18DAO), dioctadecyldimethylammonium chloride (2C
18DAC) and their mixtures with arachidic acid and poly(acrylic acid) prepared by Langmuir–Blodgett (LB) technique on gold-evaporated glass slides. The spectra show that arachidic acid and C
18DAO or 2C
18DAC molecules form well-ordered monolayers with trans zigzag conformations. The order of the alkyl chain in C
18DAO is greatly increased upon the formation of the mixed LB film. The relative intensities of infrared bands due to CH
2 and CH
3 stretching modes of the hydrocarbon chains indicate that they are tilted with respect to the surface normal in the mixed LB films of arachidic acid and C
18DAO or 2C
18DAC. The hydrocarbon chains of C
18DAO and 2C
18DAC are disordered in the mixed LB films of poly(acrylic acid) and C
18DAO or 2C
18DAC.