Patent EA-001149-B1 (EA)
Title: Acrylic copolymers as additives for inhibiting paraffin deposition in crude oils, and compositions containing same
Inventor: BRUNELLI JEAN-FRANCOIS
IPC: C10L1/14
Filed: 1997-03-14
Abstract: (Co)polymers of alkylacrylates or alkylacrylates with vinylpyridine with mean weight molecular mass Mw comprising from 5.000 to 500.000, preferably from 40.000 to 350.000, in which acrylic monomer chains, participating in a polymer chain, are chains   in which R is H or CH3  Ri is residues of saturated linear aliphatic alcohols Ri-OH, where i is a number of carbons in said residues , which comprises from 10 to 50 carbon atoms and characterized in that follow the distribution law "U", according to which i is even numbers of the upper part of 24-50 interval, with a preferable value iu and the distribution law "Non-U", according to which i is even or odd numbers of 10-22 interval, the preferable value of which inu such that inu < iu, whereby the weight ratio of the chain combination   distributed by the "U" law and the chain combination distributed by the "Non-U" lawis from 1:99 to 50:50, preferably from 5:95 to 50:50. 2. Copolymers according to claim 1, characterized in that the "Non-U" chains are alcohol acrylate chains, comprising about 10-22 carbon atoms, and the "U" chains are alcohol acrylate chains, comprising about 24-50 carbon atoms. 3. Copolymers of alkyl acrylates according to claim 1 or 2, comprising beside acrylate chains from 1 to 10 % by weight vinylpyridine chains tespective to copolymer. 4. A method for obtaining copolymers according to claim 1, characterized in that polymerization of monomer mixture is carried out, in which one part of acrylic or methacrylic esters   is obeyed to the "U" distribution law, and an additional part of the monomers esters is obeyed to the "Non-U" distribution law, whereby the weight ratio of the combination of esters, distributed by the "U" law and the combination of esters, distributed by the "Non-U" law is about 5:95 to 50:50. 5. The method according to claim 4, in which a mixture of acrylic or methacrylic esters is used obtained by mixing esters of each of the distribution categories "U" and Non-U" in weight ratio from 1:99 to 50:50, preferably from 5:95 to 50:50. 6. The method according to claim 4, in which a mixture of acrylic or methacrylic esters is used obtained by premixing alcohols of each of the distribution categories "U" and Non-U" with further esterification using acrylic or methacrylic acids. 7. The method according to claim 4, characterized in that the process is carried out in a solvent in which monomers as well as copolymers are soluble and the boiling point of which is below 300 degree C. 8. The method according to claim 7, characterized in that the solvent is xylene. 9. An additive designated for inhibiting a flow point in crude oils and for improving their rheologic properties, characterized in that said additive comprises polymers according to claim 1 and aromatic  and/or aliphatic solvent, whereby the weight concentration of copolymer in the additive is from 2 to 90%, preferably from 20 to 90%. 10. A composition, comprising a crude oil and a copolymer according to claim 1, in which copolymer comprises from 5 to 5.000 ppm, preferably from 10 to 2.00 ppm.