Similar articles

Abstract: The rheological behavior of polyvinyl acetate (PVAc) in N,N'-dimethylformamide (DMF), methyl ethyl ketone (MEK), 1,2-dichloroethane (DCE), tetrahydrofuran (THF) and toluene (TOL), polystyrene (PS) in DMF, MEK, DCE, THF and cyclohexane (CYH), and random ethylene-vinyl acetate (EVA) copolymer in DCE, TOL, CYH with and without surfactant of Span80 and in the DCE/CYH solvent mixtures with surfactant of Span80 was examined at high dilution. It was shown that the extent and type of the upsweep or downsweep (anomalous rheological behavior) of the reduced viscosity-concentration curves of these different polymers at high dilution are markedly dependent on the dielectric constant of the solvent and the polarity of the polymer used. The experimental results indicated that the anomalous rheological behavior of EVA copolymer, widely used as a flow improver, is related to its efficiency in reducing viscosity and depressing pour point of crude oil and waxy solvents.

[1] Burger, E.D., Chorn, L.G., Wahl, H.A., 1980. Studies of drag reduction conducted over a broad range of pipeline conditions when flowing prudhoe bay crude oil. J. Rheology, 24:603-626.

[2] Chatterjee, S.K., Chattjee, N., Riess, G., 1982. Interpolymer complex between polyethylene oxide and polyacrylic acid: viscometric studies in THF-Water mixtures. Mackromol. Chem., 183:481-487.

[3] Chen, T.S. and Joslyn, M.A., 1967. The effect of sugars on viscosity of pectin solutions. J. Colloid Interface Sci., 23:399-406.

[4] Cheng, Rongshi, Yang, Yu, Yan, Xiaohi, 1999. The wall effect on viscosity measurement of dilute aqueous solutions of polyethyleneglycol and polyvinyl alcohol with paraffin coated capillary viscometer. Polymer, 40:3773-3779.

[5] Choi, L.S., Yoon. T.H., Armistead, J.P., et al., 1989. Flow-induced complexation of poly(acrylic acid) and its derivatives in dilute solution. Am. Chem. Soc. Div. Polym. Chem. Polym. Prepr., 30(2):382-383.

[6] Cragg, L.H., Bigelow, C.C., 1957. Viscometric evidence of critical concentration in dilute polymer solutions. J. Polym. Sci., 24:429-437.

[7] Dondos, A. and Benoit, H., 1975. Etude viscomettrique du systene ternaire polystyrene/polymethyl acrylate de methyle/P-xylene. Makromol. Chem., 176:3441-3451.

[8] Dondos, A., Havredaki, V., Mitsou, A., 1975. Molecular dimensions of polymers dissolved in binary mixtures of polar and non-polar solvents 2. Poly(methyl Methacrylate). Mackromol. Chem., 176:1481-1488.

[9] Dondos, A., Skondras, P., Pierri, E., et al., 1983. Hydrodynamic crossover in two polymer mixtures from viscosity measurements. Makromol. Chem., 184:2153-2158.

[10] Dondos, A., Pierri, E., Skartsis, L., et al., 1988. Experimental verification of a model describing the occupied volume by polymers in solution. Makromol. Chem., 189:1685-1692.

[11] Dondos, A., Tsitsianis, C., 1992. Viscometric study of extremely dilute macromolecular solutions: critical concentration C** and the huggins constant. Polymer International, 28:151-156.

[12] Gundiah, S., Kapur, S.L., 1960. Polymer solutions IV. anomalous viscosity behavior of polystyrene and poly(methyl Acrylate) solutions at high dilutions. Makromol. Chem., 42:127-139.

[13] Interthal, W., Wilski, H., 1985. Drag reduction experiments with very large pipes. Colloid & Polym. Sci., 263:217-229.

[14] Kapur, S.L., Gundiah, S., 1958. Anomalous behavior of polymer solutions II. viscosity behavior of rubber solutions at high dilutions. J. Colloid Sci., 13:170-178.

[15] Kulicke, W.M., Kniewske, R., Hor,l H.H., 1980. Untersuchung zur flockungsfahigkeit von polyacryamide-co-acrylaten (0-100 mol% acrylamide). Angew. Makromol.Chem., 87:195-204.

[16] Lopez de Sa, T.G., Fernandez, L.M.G., Riano, J.L.A., 1988. Interaction between polyvinyl pyrrolidone and surfactant from viscometric data. Br. Polym. J., 20:39-42.

[17] Ohrn, E., 1955. Preliminary report on the influence of adsorption on capillary dimensions of viscometers. J. Polym. Sci., 17:137-140.

[18] Outer, P., Carr, C.I., Zimm, B.H., 1950. Light scattering investigation of the structure of polystyrene. J. Chem. Phys., 18:830-839.

[19] Pelton, R.H., Allen, L.H., 1983. The effects of some electrolytes on flocculation with a cationic polyacrylamide. Colloid Polym. Sci., 261:485-492.

[20] Pepper, D.C., Rutherford, P.P., 1959. The viscosity anomaly at low concentrations with polystyrenes of low molecular weight. J. Polym. Sci., 35:299-301.

[21] Pierri, E. and Dondos, A., 1987. Viscometric determination of the two critical concentrations of polymer in solution. Eur. Polym. J., 23:347-351.

[22] Pradhan, M.S., Khilar, K.C., 1994. Stability of aqueous foams with polymer additives. J. Colloid & Interface. Sci., 168:333-338.

[23] Qi, G.R., Yang, W.Y., Qian, J.W., et al., 1992. The structural effect of flow improver on rheological behavior of crude oil. Proceedings of International Symposium on Fine Chemistry and Functional Polymers, Hangzhou, Sept., p.41-42.

[24] Qian, J.W., Wang, S.C., Liu, X.L., et al., 1986. Studies on reduction effectiveness and shearing resistance of ethylene-propylene copolymers. J. of Zhejiang Univ., 20(3):20-27(in Chinese,with English abstract).

[25] Qian, J.W., He, X.Y., Li, F., et al., 1992. Study on solution behavior of cationic polyacrylamide: effect of pH on the viscosity behavior and flocculation properties. Functional Polymer, 5(3):233-236(in Chinese,with English abstract).

[26] Qian, J.W., Qi, G.R., Ding, Z.X., et al., 1996. Assessment of polymer flow improvers for crude oil by viscometry. Fuel, 75(3):307-312.

[27] Qian, J.W., Qi, G.R., Xu, Y.L., et al., 1996. Solvent effect on the action of ethylene-vinyl acetate copolymer pour point depressant in waxy solutions. J. Appl. Polym. Sci., 60:1575-1578.

[28] Shultz, A.R., 1954. Polyvinyl acetate. A Light Scattering and Viscosity Study, J. Am. Chem. Soc., 76:3422-3430.

[29] Staikos, G., Antonopoulou, P., Christou, E., 1989. A new viscometric approach to the interpolymer complexes. Polymer Bulletin, 21:209-215.

[30] Sunil Kumar, M.N., 1989. Review on polymeric and copolymeric pour point depressants for waxy crude oils and studies on bombay high crude oil. Inst. Petroleum Quaurt. J. Technical Papers, Oct./Dec., 47-70.

[31] Tadros, TH.F., 1974. The interaction of cetyltrimethylammonium bromide and sodium dodecylbenaene sulfonate with polyvinyl alcohol adsorption of the polymer-surfactant complexes on silica, J. Colloid and Interface Sci., 46:528-540.

[32] Tuijnman, C.A.F., Hermans, J.J., 1957. Precision viscometry of polyvinyl acetate in toluene. J. Polym. Sci., 25:385-401.

[33] Van Kreveln, D.W., 1990. Properties of Polymers. Elsevier, Amsterdam, p.774-789.

[34] Willianson, G.R. and Wright, B., 1965. Interactions in binary systems. J. Polym. Sci., Part A, 3: 3885-3891.

[35] Zhu, P., Yang, H., Wang, S., 1998. Viscosity behavior of poly-e-caprolactone (PCC)/polyvinyl chloride (PVC) blends in various solvents. Eur. Polym. J., 34(1):91-94.

[36] Zhu, P.W., 1995. Viscosity study of oligomer-induced shrinking of polystyrene chains in benzene. Eur. Polym. J., 31(7):659-663.