# US 11,028,308 B2 · Invert emulsifiers from DCPD copolymers and their derivatives for drilling applications

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 11,028,308 B2
- Document ID: US11028308B2
- Status: Granted
- Kind: B2
- Application number: 15/817,865
- Filed: 2017-11-20
- Published: 2018-05-24
- Granted: 2021-06-08
- Earliest claimed: 2016-11-22
- Assignees: Schlumberger Technology Corporation
- Applicants: M-I L.L.C.
- Inventors: Yiyan Chen; Dimitri M. Khramov; Glynda A. Addicks
- Web page: https://patentgrep.com/patent/US11028308B2

## CPC

- C09K 8/36: Water-in-oil emulsions
- C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE

## Abstract

Wellbore fluids and methods of drilling with the wellbore fluids are provided. One wellbore fluid may include an oleaginous continuous phase, a non-oleaginous discontinuous phase, and a polymer having a polycyclic backbone. One method may include pumping the wellbore fluid into a wellbore through an earthen formation.

## Claims

### Claim 1

A method of drilling, comprising:
pumping a wellbore fluid into a wellbore through an earthen formation, the wellbore fluid comprising:
an oleaginous continuous phase;
a non-oleaginous discontinuous phase formed as emulsion droplets; and
a polymer having a polycyclic backbone,
wherein
a particle size distribution of a majority of the emulsion droplets is less than 100 microns,
a peak of the particle size distribution of the majority of the emulsion droplets is greater than 1 micron and less than 10 microns,
a first portion of the emulsion droplets having first particle sizes of less than 10 microns, and
a second portion of the emulsion droplets have second particle sizes of greater than 10 microns and less than 100 microns.

### Claim 2 (depends on 1)

The method of claim 1, wherein the polycyclic backbone of the polymer has at least a dicyclopentadiene repeating unit.

### Claim 3 (depends on 2)

The method of claim 2, wherein the polymer having a polycyclic backbone further contains at least a styrene monomer unit.

### Claim 4 (depends on 2)

The method of claim 2, wherein the dicyclopentadiene repeating unit is derivatized with maleic anhydride.

### Claim 5 (depends on 4)

The method of claim 4, wherein the maleic anhydride is not functionalized.

### Claim 6 (depends on 4)

The method of claim 4, wherein the maleic anhydride has a functionalized anhydride group.

### Claim 7 (depends on 6)

The method of claim 6, wherein the functionalized anhydride group of the maleic anhydride has at least a hydrophilic group.

### Claim 8 (depends on 7)

The method of claim 7, wherein the functionalized anhydride group is functionalized with an alcohol, an amine, or combinations thereof.

### Claim 9 (depends on 8)

The method of claim 8, wherein the alcohol is selected from the group consisting of primary, secondary and tertiary alcohols.

### Claim 10 (depends on 8)

The method of claim 8, wherein the amine is selected from the group consisting of primary, secondary and polyfunctional amines.

### Claim 11 (depends on 1)

The method of claim 1, wherein the polymer is used in an amount ranging from 3 to 25 pounds per barrel.

### Claim 12

A method of drilling, comprising:
pumping a wellbore fluid into a wellbore through an earthen formation, the wellbore fluid comprising:
an oleaginous continuous phase;
a non-oleaginous discontinuous phase formed as emulsion droplets; and
a polymer having a polycyclic backbone and a polydispersity ranging from 1.77 to 2.48,
wherein
a particle size distribution of a majority of the emulsion droplets is less than 100 microns
a first portion of the emulsion droplets having first particle sizes of less than 10 microns, and
a second portion of the emulsion droplets have second particle sizes of greater than 10 microns and less than 100 microns.

### Claim 13 (depends on 1)

The method of claim 1, wherein an amount of the non-oleaginous discontinuous phase is at least 40% by volume of the wellbore fluid.

### Claim 14 (depends on 13)

The method of claim 13, wherein the amount of the non-oleaginous discontinuous phase is from about 40% to about 60% by volume of the wellbore fluid.