| abstract |
The present invention generally relates to aqueous, acidic compositions thickened with an amidoamine oxide gelling agent and/or viscoelastic surfactant of the general formula I: wherein R<SUB>1 </SUB>is a saturated or unsaturated, straight or branched chain aliphatic group of from about 7 to about 30 carbon atoms, R<SUB>2 </SUB>is a divalent alkylene group of 2-6 carbon atoms which may be linear or branched, substituted or unsubstituted, and R<SUB>3 </SUB>and R<SUB>4 </SUB>are independently C<SUB>1</SUB>-C<SUB>4 </SUB>alkyl or hydroxyalkyl groups or together they form a heterocyclic ring of up to six members, and R<SUB>5 </SUB>is hydrogen or a C<SUB>1</SUB>-C<SUB>4 </SUB>alkyl or hydroxyalkyl group. The aforementioned gelling agents advantageously provide gels that do not undergo phase separation over extended periods of time and exhibit high heat stability. The thickened acid gels of the invention have applications in household and industrial cleaners and degreasers, oilfield stimulation applications and the like. |