Maleic anhydride copolymer with broadly dispersed ester side chain as wax inhibitor and wax crystallization enhancer

1. A wax inhibitor composition, the composition comprising:

at least one alpha-olefin maleic anhydride copolymer of the formula

wherein R 1 is selected from hydrocarbyl groups containing 10-30 carbon atoms, and R 2 is selected from a hydrogen or hydrocarbyl groups containing 10-80 carbon atoms, wherein R 2 comprises a weight fraction of carbon numbers greater than 30, and the other R 2 can be the same or different, and wherein if R 2 is hydrogen, the other R 2 is different, and n is a number of repeating units ranging from 1 to 100.

2. The wax inhibitor composition as recited in claim 1 , wherein the at least one alpha olefin maleic anhydride copolymer is prepared by reacting an alpha-olefin containing greater than 10 carbon atoms with maleic anhydride in the presence of a free radical initiator to obtain a copolymer, followed by reacting the copolymer with an alcohol mixture having a dispersed chain length ranging from 10 to 80 carbon atoms.

3. The wax inhibitor composition as recited in claim 2 , wherein the alpha-olefin comprises a range of about 10-30 carbon atoms.

4. The wax inhibitor composition as recited in claim 2 , wherein the alpha-olefin is 1-octadecene, 1-eicosene, 1-docosene, 1-tetracosene, 1-hexacosene, 1-octacosene, 1-hexadecene, 1-tetradecene, or 1-dodecene.

5. The wax inhibitor composition as recited in claim 2 , wherein the alcohol mixture contains more than 25% by weight of alcohols in the alcohol mixture contain greater than 35 carbon atoms.

6. The wax inhibitor composition as recited in claim 2 , wherein the alcohol mixture has a dispersed chain length ranging from (i) C10-C60, (ii) C20-C70, or (iii) C30-C80.

7. The wax inhibitor composition as recited in claim 2 , wherein the alcohol mixture comprises a linear aliphatic alcohol containing more than 25% by weight of alcohols in the alcohol mixture contain greater than 35 carbon atoms.

8. A comb polymer composition, the composition comprising:

at least one alpha olefin maleic anhydride copolymer of the formula:

wherein R 3 is selected from hydrocarbyl groups containing 10-40 carbon atoms, and R 4 is selected from a hydrogen or hydrocarbyl groups containing 10-80 carbon atoms, and R 4 , if not hydrogen, comprises a weight fraction of carbon numbers greater than 30, R 5 is selected from a hydrogen or hydrocarbyl groups containing 10-80 carbon atoms, and R 5 , if not hydrogen, comprises a weight fraction of carbon numbers greater than 30, wherein R 4 and R 5 are the same or different, and when either R 4 or R 5 is hydrogen, R 4 and R 5 are different, and n is a number of repeating units ranging from 1 to 100, wherein the at least one alpha olefin maleic anhydride copolymer is prepared by reacting an alpha-olefin or alpha-olefin mixture with a chain length of greater than 10 carbon atoms with a dicarboxylic acid to obtain a copolymer, followed by reacting the copolymer with an alcohol mixture in the presence of a catalyst, wherein the alcohol mixture contains a fully saturated, linear primary alcohol, having a dispersed chain length ranging from 10 to 80 carbon atoms and wherein at least 14% by weight of the alcohol mixture comprises greater than 35 carbon atoms.

9. The comb polymer composition as recited in claim 8 , wherein the alpha-olefin or alpha-olefin mixture comprises a chain length of greater than 24 carbon atoms.

10. The comb polymer composition as recited in claim 9 , wherein the alpha-olefin is 1-octadecene, 1-eicosene, 1-docosene, 1-tetracosene, 1-hexacosene, 1-octacosene, or 1-hexadecene, 1-tetradecene, 1-dodecene, or C30-54 olefin.

11. The comb polymer composition as recited in claim 9 , wherein the dicarboxylic acid is maleic anhydride.

12. The comb polymer composition as recited in claim 9 , wherein the alcohol mixture contains more than 25% by weight of alcohols in the alcohol mixture contain greater than 35 carbon atoms.

13. The comb polymer composition as recited in claim 9 , wherein the alcohol mixture has a dispersed chain length ranging from (i) C10-C60, (ii) C20-C70, or (iii) C30-C80.

14. The comb polymer composition as recited in claim 9 , wherein the alpha-olefin has a chain length of between 24-28 carbon atoms and the alcohol mixture has a dispersed chain length of greater than 25 carbon atoms.

15. The comb polymer composition as recited in claim 9 , wherein the alpha-olefin has a chain length of greater than 30 carbon atoms and the alcohol mixture has a dispersed chain length of greater than 30 carbon atoms.

16. The comb polymer composition as recited in claim 9 , wherein the alpha-olefin has a chain length of greater than 30 carbon atoms and the alcohol mixture has a dispersed chain length of greater than 40 carbon atoms.

17. The comb polymer composition as recited in claim 8 , wherein the comb polymer composition is used to effectively treat crudes comprising long waxes containing greater than 40 carbon atoms.

18. The comb polymer composition as recited in claim 8 , wherein either R 4 or R 5 is hydrogen.

19. A method of reducing wax deposition from an oil, the method comprising:

adding to the oil an effective amount of a wax inhibitor composition comprising at least one alpha olefin maleic anhydride copolymer,

wherein the at least one alpha olefin maleic anhydride copolymer is prepared by reacting an alpha-olefin containing greater than 10 carbon atoms with maleic anhydride in the presence of a free radical initiator to obtain a copolymer, followed by reacting the copolymer with an alcohol mixture having a dispersed chain length ranging from 10 to 80 carbon atoms, wherein the alcohol mixture contains a fully saturated, linear primary alcohol and at least 14% by weight of the alcohol mixture comprises greater than 35 carbon atoms,

wherein the at least one alpha olefin maleic anhydride copolymer of the formula:

wherein R 3 is selected from hydrocarbyl groups containing 10-40 carbon atoms, and R 4 is selected from a hydrogen or hydrocarbyl groups containing 10-80 carbon atoms, and R 4 , if not hydrogen, comprises a weight fraction of carbon numbers greater than 30, R 5 is selected from a hydrogen or hydrocarbyl groups containing 10-80 carbon atoms, and R 5 , if not hydrogen, comprises a weight fraction of carbon numbers greater than 30, wherein R 4 and R 5 are the same or different, and when either R 4 or R 5 is hydrogen, R 4 and R 5 are different, and n is a number of repeating units ranging from 1 to 100.

20. The method as recited in claim 19 , wherein the alcohol mixture contains more than 25% by weight of alcohols in the alcohol mixture contain greater than 35 carbon atoms.

21. The method as recited in claim 19 , wherein the oil comprises long waxes containing greater than 40 carbon atoms.

22. The method as recited in claim 19 , wherein the weight percent of the copolymer in the wax inhibitor composition is in a range from 0.1% to 100%.

23. The method as recited in claim 19 , wherein the oil comprises a wax content of 0.1% to 100% by weight.

24. The method as recited in claim 19 , wherein the oil is a crude oil having a wax content of 0.1% to 100%.

25. The method as recited in claim 24 , wherein the weight percentage of the wax inhibitor in the crude oil is in a range from 0.001% to 1%.