A surfactant of formula (I) ##STR00001## wherein each of R.sub.1 and R.sub.2 are independently a hydrogen, an optionally substituted alkyl, an optionally substituted cycloalkyl, or an optionally substituted arylalkyl, R.sub.3 and R.sub.4 are independently an optionally substituted alkyl, an optionally substituted cycloalkyl, or an optionally substituted arylalkyl, x is an integer in a range of 2-8, y is an integer in a range of 1-15, z is an integer in a range of 4-10, n is an integer in a range of 2-5, and A is one of a carboxybetaine group, a sulfobetaine group, or a hydroxy sulfobetaine group. An oil and gas well servicing fluid containing the surfactant and methods of servicing an oil and gas well are also described.

A surfactant of formula (I) ##STR00001## wherein each of R.sub.1 and R.sub.2 are independently a hydrogen, an optionally substituted alkyl, an optionally substituted cycloalkyl, or an optionally substituted arylalkyl, R.sub.3 and R.sub.4 are independently an optionally substituted alkyl, an optionally substituted cycloalkyl, or an optionally substituted arylalkyl, x is an integer in a range of 2-8, y is an integer in a range of 1-15, z is an integer in a range of 4-10, n is an integer in a range of 2-5, and A is one of a carboxybetaine group, a sulfobetaine group, or a hydroxy sulfobetaine group. An oil and gas well servicing fluid containing the surfactant and methods of servicing an oil and gas well are also described.

A sulfuric acid ester containing a plurality of carbonyl groups or a salt thereof, and a surfactant. The sulfuric acid ester is a compound represented by the following formula:
R.sup.1—C(═O)—R.sup.2—C(═O)—R.sup.3—OSO.sub.3X
wherein R.sup.1, R.sup.2 and R.sup.3 are defined herein; X is H, a metal atom, NR.sup.4.sub.4, imidazolium optionally containing a substituent, pyridinium optionally containing a substituent, or phosphonium optionally containing a substituent, where R.sup.4s are each H or an organic group and are the same as or different from each other; and any two of R.sup.1, R.sup.2, and R.sup.3 optionally bind to each other to form a ring. Also disclosed is a surfactant containing the sulfuric acid ester and an aqueous dispersant containing the sulfuric acid ester.

A sulfuric acid ester containing a plurality of carbonyl groups or a salt thereof, and a surfactant. The sulfuric acid ester is a compound represented by the following formula:
R.sup.1—C(═O)—R.sup.2—C(═O)—R.sup.3—OSO.sub.3X
wherein R.sup.1, R.sup.2 and R.sup.3 are defined herein; X is H, a metal atom, NR.sup.4.sub.4, imidazolium optionally containing a substituent, pyridinium optionally containing a substituent, or phosphonium optionally containing a substituent, where R.sup.4s are each H or an organic group and are the same as or different from each other; and any two of R.sup.1, R.sup.2, and R.sup.3 optionally bind to each other to form a ring. Also disclosed is a surfactant containing the sulfuric acid ester and an aqueous dispersant containing the sulfuric acid ester.

A surfactant of formula (I)

##STR00001##

wherein each of R.sub.1 and R.sub.2 are independently a hydrogen, an optionally substituted alkyl, an optionally substituted cycloalkyl, or an optionally substituted arylalkyl, R.sub.3 and R.sub.4 are independently an optionally substituted alkyl, an optionally substituted cycloalkyl, or an optionally substituted arylalkyl, x is an integer in a range of 2-8, y is an integer in a range of 1-15, z is an integer in a range of 4-10, n is an integer in a range of 2-5, and A is one of a carboxybetaine group, a sulfobetaine group, or a hydroxy sulfobetaine group. An oil and gas well servicing fluid containing the surfactant and methods of servicing an oil and gas well are also described.

A surfactant of formula (I)

##STR00001##

wherein each of R.sub.1 and R.sub.2 are independently a hydrogen, an optionally substituted alkyl, an optionally substituted cycloalkyl, or an optionally substituted arylalkyl, R.sub.3 and R.sub.4 are independently an optionally substituted alkyl, an optionally substituted cycloalkyl, or an optionally substituted arylalkyl, x is an integer in a range of 2-8, y is an integer in a range of 1-15, z is an integer in a range of 4-10, n is an integer in a range of 2-5, and A is one of a carboxybetaine group, a sulfobetaine group, or a hydroxy sulfobetaine group. An oil and gas well servicing fluid containing the surfactant and methods of servicing an oil and gas well are also described.

The invention provides an associative polymer, a powder, and a process for making a powder comprising, networking one or more associative polymer(s) and one or more optional surfactant(s) to form a wet gel, and forming a powder from the wet gel, wherein the associative polymer(s) have a weight average molecular weight of from about 10 kDa to about 2,000 kDa.

The invention provides an associative polymer, a powder, and a process for making a powder comprising, networking one or more associative polymer(s) and one or more optional surfactant(s) to form a wet gel, and forming a powder from the wet gel, wherein the associative polymer(s) have a weight average molecular weight of from about 10 kDa to about 2,000 kDa.

Sulfated oligohydroxycarboxylic acid esters have the general formula (I): ##STR00001##
wherein at least one of the radicals A is —SO.sub.3B. Cosmetic and pharmaceutical agents contain said esters. These esters are effective as anionic surfactants.

Sulfated oligohydroxycarboxylic acid esters have the general formula (I): ##STR00001##
wherein at least one of the radicals A is —SO.sub.3B. Cosmetic and pharmaceutical agents contain said esters. These esters are effective as anionic surfactants.