Probing the balance of Telechelic Polymers Bridging and Screened-Coulomb Interactions in Microemulsion System

Abstract

Abstract The structural properties of neutral oil-in-water (O/W) microemulsions nanodroplets in the presence of telechelic polymers PEO modified with two hydrophobic end functions (PEO- 2m) were studied by Small-Angle Neutron Scattering (SANS). We show that the unknown attractive interaction introduced by the addition of PEO-2m, can could be balanced by a known repulsion interaction due to the addition of a cationic surfactant Cp +, which causes a progressive transformation of the bridges connecting the nanodroplets into loops. For this, we compute the structure factor S(q) with an effective pair potential, using the Ornstein Zernicke (OZ) integral equation approach with the Hypernetted Chain (HNC) closure relation. Generally, the agreement between the neutron scattering spectra and the numerical study is reasonable and allows a detailed description for each sample.