Homopolymers and copolymers of acrylic as additives for the inhibition of paraffins in the crude oils and compositions containing the oils and additives

摘要

Copolymers of alkyl acrylates or alkyl acrylates/vinylpyridine of molecular wt. (Mw) 5000 - 500000 (preferably 40000 - 350000), the monomer motifs of which correspond to -(-CH2-C(R)(C(O)ORi)-)- (I) where R = H or Me, Ri = residues of a linear saturated alcohol RiOH and i is the number of C atoms ranging from 10 - 50C, and which conforms to a distribution law U in which the i's are even numbers developed over the upper part of the range (24 - 50), the centre value being iu, and a distribution non-U where the i's are even or odd numbers over the lower part of the range (10-22) with a central value inu, such that inu is less than iu. The wt. ratio of the assemblage of motifs (I) distributed according to U to the non-U distribution is from 1:99 to 50:50 (preferably 5:95 to 50:50). Also claimed is the procedure for obtaining the copolymers, additive compositions containing the copolymers and crude oil compositions containing the copolymers.