| abstract |
The present invention provides a polyethylenenglycol (PEG) ester surfactant comprising at least onenpolyethylene glycol moiety and at least one fatty acylnmoiety characterised in that said moieties are linked byna linkage incorporating a biodegradable methylenendiester unit of formula (I)n -CO.O.C(R 1 )(R 2 ).O.CO- nwhere R 1 and R 2 may, for example, each be a hydrogen atomnor a monovalent organic group attached through a carbonnatom or R 1 and R 2 together may, for example, form andivalent organic group attached through carbon atoms. |