CLUSTER AND NETWORK FORMATION TOWARD PERCOLATION IN THE MICROEMULSIONL-2 PHASE FORMED BY AN AMPHIPHILIC TRIBLOCK COPOLYMER AND WATER IN P-XYLENE

Evidence is presented for cluster formation in the L-2 phase of system s with the triblock copolymer Pluronic L64, water, and p-xylene. The s tatic and dynamic properties have been investigated by time-resolved f luorescence quenching, rheology, conductometry, and dynamic light scat tering as a function of the temperature and water content. A network o f connected swollen reversed micelles forms a percolation cluster at t emperatures below 20 degrees C. Droplet linking, present over the whol e temperature range investigated, occurs via the two hydrophilic amphi phile moieties. Interdroplet connections are favored as the solvent qu ality for the hydrophobic copolymer moiety becomes worse on decreasing the temperature.