Patent EP-0177308-A2 (EP)
Inventor: CHILDS JERRY DALE
IPC: C04B24/00
Filed: 1985-09-27
Abstract: 1. A set retarded cement composition for cementing high temperature zones in wells, comprising: 
     
         
         hydraulic cement; sufficient water to form a pumpable slurry; and 
         an effective amount of one or more methylene phosphonic acid derivative retarders selected from: (a) compounds having the general formula:
       
wherein: 
         R 1 , R 2  and R 3  are independently hydrogen, -CH 2 P0 3 (X) 2  or ―CH 2 CH 2 ―O―PO 3 (X) 2  with the limitation that one of R i , R 2  and R 3  is always ―CH 2 PO 3 (X) 2  or ―CH 2 CH 2 ―O―PO 3 (X) 2 ; 
         X is hydrogen, an alkali metal cation, ammonium, a protonated amine or an alkaline earth metal cation in which case there is only one X per methylene phosphonate group; and 
         at least one X is hydrogen which is associated with the nitrogen atom by way of an intramolecular hydrogen bond between the nitrogen atom and an oxygen atom attached to a phosphorus atom; (b) compounds having the structural formula:
       
wherein: 
         n is an integer from 1 to 4; 
         R 1  is hydrogen or -CH 2 PO 3 (X) 2 ; 
         R 2  is hydrogen, -CH 2 PO 3 (X) 2  or ―CH 2 CH 2 N(R 3 ) 2  wherein R 3  is hydrogen or ―CH 2 PO 3 (X) 2 ; 
         X is hydrogen, an alkali metal cation, ammonium, a protonated amine or an alkaline earth metal cation in which case there is only one X per methylene phosphonate group; and 
         at least one of R 1 , R 2  or R 3  is ―CH 2 PO 3 (X) 2  and one X is hydrogen which is associated with a nitrogen atom by way of an intramolecular hydrogen bond between the nitrogen atom and an oxygen bond between the nitrogen atom and an oxygen atom attached to a phosphorus atom; (c) compounds having the structural formula:
       
wherein: 
         n is an integer from 0 to 4; R, is hydrogen or ―CHPO 3 (X) 2 ; R 2  is hydrogen, ―CH 2 PO 3 (X) 2  or -CH 2 CH 2 N(R 4 ) 2  wherein R 4  is hydrogen or ―CH 2 PO 3 (X) 2 ; R 3  is ―N(R 5 ) 2  or
     wherein R 5  is hydrogen or ―CH 2 PO 3 (X) 2 ; 
         X is hydrogen, an alkali metal cation, ammonium, a protonated amine or an alkaline earth metal cation in which case there is only one X per methylene phosphonate group; and 
         at least one of R l , R 2  or R 3  is ―CH 2 PO 3 (X) 2  and one X is hydrogen which is associated with a nitrogen atom by way of an intramolecular hydrogen bond between the nitrogen atom and an oxygen atom attached to a phosphorus atom; (d) compounds having the structural formula:
       
or
     or
     wherein: 
         n is an integer from 2 to 6; 
         R is hydrogen, ―CH 2 PO 3 (X) 2  or ―CH 2 CH 2 N(R 1 ) 2  wherein R, is hydrogen or ―CH 2 PO 3 (X) 2 ; 
         X is hydrogen, an alkali metal cation, ammonium, a protonated amine or an alkaline earth metal cation in which case there is only one X per methylene phosphonate group; and 
         at least one R is -CH 2 P0 3 (X) 2  and one X is hydrogen which is associated with a nitrogen atom by way of an intramolecular hydrogen bond between the nitrogen atom 
         and an oxygen atom attached to a phosphorus atom; (e) compounds having the structural formula:
     
     wherein: 
         R, is hydrogen or -CH 3 ; 
         R 2  is ―CH 2 PO 3 (X) 2  -CH 2 NHCH 2 P0 3 (X) 2 ; 
         X is hydrogen, an alkali metal action, ammonium, a protonated amine or an alkaline earth metal cation in which case there is only one X per methylene phosphonate group; and 
         when nitrogen is present, at least one X is hydrogen which is associated with the nitrogen atom by way of an intramolecular hydrogen bond between the nitrogen atom and an oxygen atom attached to a phosphorous atom. The compositions may also further comprise a hydratable gel-forming material.