Shale swelling inhibitors

Abstract

The present invention provides amidic polymers, which exhibit shale swelling inhibitor activity having improved bio-degradability. The amidic polymers of the invention may be employed in a wide variety of compositions, particularly in subterranean drilling operations. Non-limiting generic structures of the amidic polymers are set out below: (1) wherein R 1 -R 3 and integers m and n are defined herein.

1 - 13 . (canceled) 
     
     
         14 . An amidic polymer comprising a (a) polymer having a hydroxyl group reacted with a (c) vinyl amide to provide the amidic polymer. 
     
     
         15 . The amidic polymer according to  claim 14 , wherein the (a) polymer having a hydroxyl group is selected from the group consisting of partially and fully hydrolyzed poly(vinyl alcohol)s, polysaccharides, and mixtures thereof. 
     
     
         16 . The amidic polymer according to  claim 15 , wherein the polysaccharides are derived from celluloses, hydroxyethyl celluloses, carboxymethyl celluloses, hydroxyethyl celluloses, hydropropyl celluloses, hydroxypropyl methyl celluloses, ethyl celluloses, carageenans, chitosans, chondroitin sulfates, heparins, hyaluronic acids, starches, chitins, perctins, guars, xanthans, dextrans, welan gums, gellan gums, diutans, pullulana, and mixtures thereof. 
     
     
         17 . The amidic polymer according to  claim 14 , wherein the (c) vinyl amide is selected from the group consisting of N-vinyl pyrrolidone; N-vinyl piperidone; N-vinyl caprolactam; N-vinyl-3-methyl pyrrolidone; N-vinyl-4-methyl pyrrolidone; N-vinyl-5-methyl pyrrolidone; N-vinyl-3-ethyl pyrrolidone; N-vinyl-3-butyl pyrrolidone; N-vinyl-3,3-dimethyl pyrrolidone; N-vinyl-4,5-dimethyl pyrrolidone; N-vinyl-5,5-dimethyl pyrrolidone; N-vinyl-3,3,5-trimethyl pyrrolidone; N-vinyl-5-methyl-5-ethyl pyrrolidone; N-vinyl-3,4,5-trimethyl-3-ethyl pyrrolidone; N-vinyl-6-methyl-2-piperidone; N-vinyl-6-ethyl-2-piperidone; N-vinyl-3,5-dimethyl-2-piperidone; N-vinyl-4,4-dimethyl-2-piperidone; N-vinyl-6-propyl-2-piperidone; N-vinyl-3-octyl piperidone; N-vinyl-7-methyl caprolactam; N-vinyl-7-ethyl caprolactam; N-vinyl-4-isopropyl caprolactam; N-vinyl-5-isopropyl caprolactam; N-vinyl-4-butyl caprolactam; N-vinyl formamide; N-vinyl acetamide; N-(2,2-dichloro-vinyl)-propionamide; N-ethenyl acetamide; cis-N-propenyl acetamide; N-vinyl-N-methyl acetamide; N-vinyl-N,N-propyl propionamide; N-acryloyl piperidone; N-acryloyl pyrrolidone; ethyl acryloyl pyrrolidone; methyl acryloyl pyrrolidone; N-acryloyl caprolactam; ethyl acryloyl caprolactam; methyl acryloyl caprolactam; N-cyclohexylacrylamide; N-cyclopentylacrylamide; acrylamide, N-butoxymethylacrylamide; N,N-dibutylacrylamide; N-butylacrylamide; diacetoneacrylamide; N-(N,N-dimethylamino)ethyl acrylamide; N,N-diethylacrylamide; N,N-dimethylacrylamide; N-dodecylmethacrylamide; N-ethylacrylamide; N-ethylmethacrylamide; N-isopropylacrylamide; N-isopropylmethacrylamide; β,β-N,N-tetramethylacrylamide; N-methylolacrylamide; N-methyl acrylamide; N-octadecylacrylamide; N-octylacrylamide; N-phenylacrylamide; trichloroacrylamide; and mixtures thereof. 
     
     
         18 . The amidic polymer according to  claim 14 , wherein the polymer is represented by the structure: 
       
         
           
           
               
               
           
         
       
       wherein R 1  is a polymer having a hydroxyl group; m is an integer ranging from about 1 to about 100,000; and n is an integer ranging from 1-3. 
     
     
         19 . The amidic polymer according to  claim 18 , wherein R 1  is a polymer having a hydroxyl group selected from the group consisting of partially and fully hydrolyzed poly(vinyl alcohol)s, polysaccharides, and mixtures thereof. 
     
     
         20 . The amidic polymer according to  claim 19 , wherein the polysaccharides are derived from celluloses, hydroxyethyl celluloses, carboxymethyl celluloses, hydroxyethyl celluloses, hydropropyl celluloses, hydroxypropyl methyl celluloses, ethyl celluloses, carageenans, chitosans, chondroitin sulfates, heparins, hyaluronic acids, starches, chitins, perctins, guars, xanthans, dextrans, welan gums, gellan gums, diutans, pullulana, and mixtures thereof. 
     
     
         21 . The amidic polymer according to  claim 18 , wherein n is an integer ranging from 1-2. 
     
     
         22 . The amidic polymer according to  claim 18 , wherein m is an integer ranging from 1 to about 750,000. 
     
     
         23 . The amidic polymer according to  claim 18 , wherein the polymer is selected from the group consisting of: 
       
         
           
           
               
               
           
         
       
       wherein x is an integer ranging from 1 to about 1,000,000; y is an integer ranging from 1 to about 1,000,000; w is an integer ranging from 1 to about 1,000,000; and v is an integer ranging from 1 to about 1,000,000. 
     
     
         24 - 96 . (canceled)