Drilling fluids

Patent · Tue Aug 05 04:00:00 EDT 1986

OSTI ID:5310287

Irvin, H B; Stahl, G A; Clark, E

A method is described of preparing a composition suitable for use as a drilling fluid comprising the steps of: (a) copolymerizing a hydrophilic vinyl monomer selected from the group consisting of acrylic acid, methacrylic acid, other related monomers and mixtures and any two or more thereof with at least one hydrophobic vinyl monomer selected from the group consisting of acrylic acid esters, methacrylic acid esters, vinyl esters of saturated monocarboxylic acids having from 1 to 3 carbon atoms, and combinations of any two or more thereof under polymerization conditions in an inert low chain transfer organic liquid medium selected from the group consisting of n-hexane, cyclohexane and chlorofluorocarbons at a polymerization temperature and for a period of polymerization time sufficient to produce a copolymer having a weight average molecular weight in the range from about 100,000 to about 500,000; (b) contacting the resulting copolymer in the inert, low chain transfer, organic liquid medium selected from the group consisting of n-hexane, cyclohexane and chlorofluorocarbons with an aqueous solution of sodium hydroxide which is present in a quantity sufficient to raise the pH of the subsequently dried copolymer salt in the polymer solution in water of at least about 1 weight percent in concentration to a value in the range from about 5.3 to about 12 to produce the salt form of the resulting copolymer; (c) drying the salt form of the resulting copolymer produced by step (b) to produce a dried copolymer salt; (d) adding a quantity of the dried copolymer salt produced in accordance with step (c) to a quantity of a mixture comprising water and a clay substance suspended in the water; and (e) mixing the dried copolymer salt, the water and the clay substance to produce a drilling fluid.

• Assignee: Phillips Petroleum Co., Bartlesville, OK
• Patent Number(s): US 4604216
• OSTI ID: 5310287
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020300* -- Petroleum-- Drilling & Production
ACRYLIC ACID
ALKALI METAL COMPOUNDS
ALKANES
AQUEOUS SOLUTIONS
CARBOXYLIC ACID ESTERS
CARBOXYLIC ACIDS
CHEMICAL PREPARATION
CHEMICAL REACTIONS
CLAYS
COPOLYMERIZATION
COPOLYMERS
CYCLOALKANES
CYCLOHEXANE
DISPERSIONS
DRILLING FLUIDS
DRYING
ESTERS
FLUIDS
HEXANE
HYDROCARBONS
HYDROGEN COMPOUNDS
HYDROXIDES
METHACRYLIC ACID
METHACRYLIC ACID ESTERS
MIXTURES
MOLECULAR WEIGHT
MONOCARBOXYLIC ACIDS
MONOMERS
NATURAL GAS WELLS
OIL WELLS
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC POLYMERS
OXYGEN COMPOUNDS
PH VALUE
POLYMERIZATION
POLYMERS
QUANTITY RATIO
SODIUM COMPOUNDS
SODIUM HYDROXIDES
SOLUTIONS
SYNTHESIS
VINYL MONOMERS
WATER
WELLS