US 5,204,183 A · Composition comprising polymer encapsulant for sealing layer encapsulated substrate

Abstract

An encapsulated breaker chemical composition used in a fracturing process in an oil or gas stimulation operation which comprises: (a) a breaker chemical; (b) a water soluble sealing layer, such as urea, having a thickness within the range of about 1 to about 30 microns deposited on the surface of said breaker chemical and encapsulating said breaker chemical; and (c) a pinhole free coating of a neutralized sulfonated elastomeric polymer of about 2 to about 80 microns thick deposited onto the surface of the coated breaker chemical, wherein said neutralized sulfonated polymer encapsulates the breaker chemical and is permeable to the breaker chemical.

Claims7

Dependent claims

An encapsulated particulate composition comprising:

(a) a solid particulate substrate;
(b) a water soluble sealing layer having a thickness of at least about 1 micron deposited onto the surface of particles of said substrate and encapsulating said substrate;
(c) a coating substantially free of pinholes comprising a neutralized sulfonated elastomeric polymer having a thickness of at least about 1 micron deposited on the sealing layer surface of particles of said substrate, wherein said neutralized sulfonated polymer encapsulates and is permeable to said substrate under conditions of use;
and
(d) a layer of thermoplastic polymer overcoating said coating.

2 more elements

Dependencies are inferred from the claim text.

Facts

Application

07/816,915Filed 3 Jan 1992 · division

Priority

4 Dec 1989

Granted

20 Apr 1993

Term ends

Not estimatedThe source records don’t support an estimate.

Classification10 codes

C09K 8/92
Compositions for stimulating production by acting on the underground formation: characterised by their form or by the form of their components,…
C09K 8/62
Compositions for stimulating production by acting on the underground formation: compositions for forming crevices or fractures
Y10T 428/263
Web or sheet containing structurally defined element or component, the element or component having a specified physical dimension: coating layer…
Y10T 428/2989
Particulate matter [e.g., sphere, flake, etc.]: microcapsule with solid core [includes liposome]

Family

Serial446,572Parent of this continuation-in-part · filed 4 Dec 1989

Serial446,573Parent of this continuation-in-part · filed 4 Dec 1989

Serial446,736Parent of this continuation-in-part · filed 6 Dec 1989

Serial637,391Parent of this division · filed 4 Jan 1991

US 5,102,559 AParent of this division

US 5,204,183 AThis patent

From the US filing history. Foreign family members aren’t listed.

Composition comprising polymer encapsulant for sealing layer encapsulated substrate

Life of this patent

Composition comprising polymer encapsulant for sealing layer encapsulated substrate

Life of this patent

Abstract

Claims7