Aq polymer soln - which does not undergo shear degradation when forcibly displaced

摘要

A water-soluble compsn. comprises (I) 2-92 wt % of a synthetic, water-soluble, solid polyamide or polyethylene oxide of ave. mol. wt 500,000, the polymer being useful in concns. of 20-50,000 p.p.m. and being dispersed in (2) 8-98 wt % of a liquid surfactant which comprises an oxyalkylated adduct of a hydrophobic polyol and selected from (a) a cpd. of formula: Y (C3H6O)n (C2H4O)m H x, where Y is the residue of a 2-6C organic cpd. and contng. x reactive H atoms in which x is =2, n has a value such that the mol. wt. of the polyoxypropylene base is =900 is not 4000 and m has a value such that the oxyethylene content of the molecule is 10-90 wt % (b) the adducts of 8-22C aliphatic alcohols with ethylene- or propylene-oxide or mixtures of these, the adducts comprising 40-80 wt % of ethylene oxide and having a mol. wt. of 400-1000, and (c) cpds. of formula: Y (- P - E - H)x where Y is the nucleus of an organic reactive H cpd. contng. x reactive H atoms and having =6, inclusive, C atoms, x is an integer, P is a hydrophobic polyoxyalkylene chain having an O/C atom ratio of is not 0.40, the mol. wt of P and the value of x being such that the molecule, excluding E, has a mol wt. of =400-900 and =25,000 and E is a hydrophilic heteric polyoxyalkylene chain which (I) containsoxyethylene gps. and =5 wt % of higher mol wt =3C oxyalkylene gps. and (2) has an ave. O/C atom ratio 0.40, E being present in the compsn. to the extent that it constitutes 50-90 wt % of the total compsn. The aq. soln. can be forcibly displaced by a pump etc. without shear degradation of the polymer component, and is useful in waterflooding oil recovery processes.