Abstract
Recycling of PET waste was carried out in presence of diethanolamine and manganese acetate as catalyst. The produced oligomers were reacted with stearic acid and polyethylene glycol, PEG, which have different molecular weights 400, 1,000, and 4,000 to produce nonionic polymeric surfactants having different hydrophilic-hydrophobic balance (HLB). The surface tension, critical micelle concentration (CMC), and surface activities were determined at different temperatures. Surface parameters such as surface excess concentration Γ
max
, the area per molecule at interface A
min
and the effectiveness of surface tension reduction (Π
CMC
) were determined from the adsorption isotherms of the prepared surfactants. From the adsorption isotherm, some thermodynamic data for the adsorption process are calculated and discussed.