US 9,790,415 B1 · Modified silicon dioxide nano-particles and preparation method thereof, and drilling fluid suitable for shale gas wells

Abstract

The present invention relates to the petroleum drilling fluid field, and discloses a modified silicon dioxide nano-particle comprising a modifying polymer chain composed of structural units provided by one or more of monomers represented by the following formula (1) and one or more of monomers represented by the following formula (2). The present invention provides a method for preparing modified silicon dioxide nano-particles and a drilling fluid suitable for shale gas wells containing the modified silicon dioxide nano-particles as a plugging agent. When the modified silicon dioxide nano-particles provided in the present invention are used as a plugging agent in a drilling fluid, they will not agglomerate into large-size particles, and can achieve a good plugging effect.

Claims20

Dependent claims

A modified silicon dioxide nano-particle including a modifying group,

the modifying group comprises a modifying polymer chain composed of structural units provided by one or more monomers represented by formula (1) and one or more monomers represented by formula (2);
in the modifying polymer chain, the molar ratio of the structural units provided by the monomers represented by formula (1) to the structural units provided by the monomers represented by formula (2) is 1:0.5-5;
the weight-average molecular weight of the modifying polymer chain is 100,000-2,500,000 g/mol;
wherein one of R1-R5 is -L″-SO3H and the rest of R1-R5 are independently selected from H, —OH, halogen, and C1-C10 alkyl;
L, L′ and L″ are independently selected from C0-C10 alkylene.

2 more elements

Dependencies are inferred from the claim text.

Facts

Application

15/489,210Filed 17 Apr 2017

Priority

CN 2016 1 030813011 May 2016

Granted

17 Oct 2017

Term ends

Not estimatedThe source records don’t support an estimate.

Classification18 codes

C09C 1/3081
Silicic acid: treatment with organo-silicon compounds
C09K 8/035
Specific additives for general use in well-drilling compositions: organic additives
C01B 33/18
Silica; Hydrates thereof, e.g. lepidoic silicic acid: preparation of finely divided silica neither in sol nor in gel form; After-treatment thereof
C08F 222/385
Amides: monomers containing two or more acrylamide groups, e.g. N,N'-methylenebisacrylamide

Modified silicon dioxide nano-particles and preparation method thereof, and drilling fluid suitable for shale gas wells

Life of this patent

Modified silicon dioxide nano-particles and preparation method thereof, and drilling fluid suitable for shale gas wells

Life of this patent

Abstract

Claims20