Aggregation of P-terphenyl along with PMMA/SA at the Langmuir and Langmuir-Blodgett Films

Molecular aggregation and monolayer characteristics of non-amphiphilic p-terphenyl (TP) mixed with either polymethyl methacrylate (PMMA) or stearic acid (SA) at the air-water interface were investigated. The miscibility of the two components was evaluated by measuring and analyzing surface pressure versus area per molecule (pi-A) isotherm. Both attractive and repulsive interactions between the sample (TP) and the matrix (PMMA or SA) were observed depending on the composition and microenvironment. TP and PMMA/SA were not completely miscible in the mixed monolayer. Aggregation and phase separation between sample TP and matrix molecule was revealed by UV-Vis absorption spectroscopic studies and confirmed by scanning electron micrograpgh of LB films.