Abstract A series of 21 nonionic detergents based on epoxidized sperm oil, epoxidized methyl oleate, and epoxidized butyl tallate are discussed. The materials were synthesized by alcholysis of the oxirane oxygen in the presence of boron trifluoride. Benzene was used as a solvent to act as a coupling agent for the unreacted materials. Methoxy polyoxyethylene alcohols were used as the hydrophilic alcohols with which the epoxidized esters were reacted. Physical properties and performance characteristics of the various compounds synthesized are catalogued and the reaction itself is characterized. It is shown that the properties of the materials can be varied by varying both the size of the polyoxyethylene moiety attached to the ester and the characteristics of the ester itself. These materials all appear to be low foaming wetting agents and emulsifying agents. It is felt that these materials offer a definite potential for the use of epxodized natural fats and natural fat derivatives for the custom synthesis of tailor made surface active agents. Being based on naturally occurring straight chain materials they would als be biologically degradable.