Molecular weight distribution of nonionic surfactants. III. Foam, wetting, detergency, emulsification and solubility properties of normal distribution and homogeneous p,t‐octylphenoxyethoxyethanols

Abstract

AbstractThe effect of mol wt distribution on the foaming, wetting, detergency, emulsification and solubility properties of p,t‐octylphenoxyethoxy‐ethanols (OPE's) has been studied by comparing normal distribution and homogeneous compounds: Ross‐Miles foam studies indicate that, although homogeneous OPE7‐10 are higher in initial foam height than normal distribution OPE7‐10, their foam stability is poorer. Hard surface and textile wetting were studied by contact angle determinations and the Draves' skein test, respectively. An exact correlation exists between hard surface wetting by solutions of OPE's of a Teflon surface and surface tension lowering. Normal distribution OPE's are, in general, better hard surface wetting agents than the corresponding homogeneous compounds. In textile wetting, normal distribution OPE5‐10 are approximately equivalent in performance and by implication are probably equivalent in wetting performance to the corresponding homogeneous compounds. Hard surface detergency studies show that normal distribution OPE's are generally slightly superior in detersive power to homogeneous OPE's at corresponding ethylene oxide chain lengths. OPE10 is the best hard surface detergent of the OPE series, there being no distinguishable difference in performance between homogeneous and normal distribution OPE10. Emulsification studies on the system, water‐isooctane, show that only normal distribution OPE5 is capable of forming stable o/w emulsions. Both homogeneous and normal distribution OPE3 and OPE4 form stable w/o (invert) emulsions. Solubility studies in isooctane and Ultrasene show that homogeneous OPE4 is soluble at lower temp than the corresponding normal distribution compound. Studies of aqueous OPE solutions at temp above their cloud points show that solubility of both homogeneous and normal distribution materials is of the same order of magnitude as their critical micelle concn and that homogeneous OPE4 is more soluble than normal distribution OPE4.