Aqueous hydraulic cement slurry

Claim 1

In aqueous hydraulic cement slurry compositions comprising water, hydraulic cement, surfactant and polyalkylenepolyamine fluid loss additive; the improvement which comprises employing as said fluid loss additive, at least one composition prepared by reacting (A) at least one composition prepared by reacting (1) a polyalkylenepolyamine composition having an average molecular weight of from about 60 to about 500 with (2) at least one alkylene dihalide with (B) at least one of (2) an epihalohydrin or dihalohydrin, (2) an adduct of (a) an epihalohydrin or dihalohydrin and (b) an alkylenediamine, polyalkylenepolyamine having an average molecular weight of from about 60 to about 500 or mixtures thereof or (3) mixtures thereof; and wherein (C) component (A-1) and component (A-2) are reacted in quantities such that the quantity of A-2 used is less than the amount need to form a gel by an amount (expressed as weight of carbon and hydrogen contained in A-2) of from about 0.8% to about 5% of the weight of carbon plus hydrogen plus nitrogen present in the reaction mixture when a gel would be formed; (D) components (A) and (B) are employed in quantities which provide a polyamine which gives a fluid loss of less than 60 ml, according to the API RP 10B fluid loss test described in the examples.