A kind of preparation method of polygonal clathrate siloxane supercritical carbon dioxide thickener

Abstract

The invention relates to a preparation method of a polygonal clathrate siloxane supercritical carbon dioxide thickener. Including: (1) In an organic solvent, react the hydroxyl double-capped siloxane with sodium silanolate to prepare the double-ended sodium-blocked siloxane; then, make the double-ended sodium-blocked siloxane react with the Silane reaction to produce monohydrogen-terminated siloxane; (2) In the presence of a catalyst, monohydrogen-terminated siloxane is reacted with a catalyst in a cyclohexane solution of cage-shaped stereocyclic siloxane to prepare a polygonal cage Silicone polymer. The obtained siloxane polymer has a good thickening ability of thickening supercritical carbon dioxide, which improves the siloxane in CO 2 Enhance the solvency, reduce the amount of co-solvent.

Description

technical field [0001] The invention relates to a preparation method of a polygonal cage siloxane supercritical carbon dioxide thickener, and belongs to the technical field of petroleum exploitation. Background technique [0002] The supercritical carbon dioxide fracturing technology can reduce the water sensitivity and water lock of the underground reservoir caused by hydraulic fracturing when the low permeability shale reservoir is reformed. In view of the low fluidity and high friction of the oil-based fracturing fluid, it can reduce the fracture of the reservoir. Friction and formation damage can also improve crude oil rheology. However, the weak sand-carrying performance and fingering phenomenon caused by the low viscosity of supercritical carbon dioxide are not conducive to CO 2 The improvement of the fracturing fluid sweep coefficient and the oil and gas development of low permeability reservoirs. In order to solve this problem, researchers have carried out a lot of...

AI Technical Summary

Problems solved by technology

Although fluorine-containing polymers have excellent thickening effects when used as thickeners, they are easy to interact with groundwater and remain in the reservoir, polluting low-permeability reservoirs and water resources, and then circulate in the biosphere, damaging the environment, and can be in the body. biosphere accumulation

In addition, fluorine-containing thickeners are expensive and costly to use, which is not conducive to industrial applications

Another type of hydrocarbon thickener, although the preparation cost is low, has high dissolution pressure and poor thickening effect, which cannot meet the fracturing needs of low-permeability reservoirs.

currently available for thickening CO 2 The types of fluorine-containing thickeners and hydrocarbon thickeners are limited. Although there are many advantages, due to the defects of preparation cost or environmental pollution, it hinders the supercritical CO 2 Application of Fracturing Technology in Fracturing Stimulation of Low Permeability Reservoir

[0003] Recently, the research on supercritical carbon dioxide thickener of siloxane polymer has also been carried out, for example CN107236091A provides a kind of supercritical carbon dioxide thickener, and component is: (a) polydimethylsiloxane; (b) Acrylate compound; (c) styrene compound; (d) initiator; (e) emulsifier; but its cosolvent consumption is large and its solubility is poor

CN108003349A provides a siloxane polymer supercritical carbon dioxide thickener for fracturing, which is prepared by reacting aromatic amide group-terminated side chain modified siloxane polymer with hydrogen-containing siloxane; the thickener The thickening agent is better, but the test temperature and pressure are low, the amount of solvent is large, and the solubility of the thickener in carbon dioxide needs to be further improved

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