abstract |
Quaternary ammonium compounds of formula (I): wherein R 0 , R 1 , R 2 and R 3 are each independently an optionally substituted hydrocarbyl group, X is a linking group, and R 4 is an optionally substituted alkylene group group, R5 is hydrogen or an optionally substituted alkyl, alkenyl or aryl group, and n is 0 or a positive integer, provided that when R5 is hydrogen, n is not 0 . |