Cathode non-mixed type oil displacement surfactants and preparation method and application thereof

The invention relates to cathode non-mixed type oil displacement surfactants and a preparation method and application thereof. Mainly the problems that surfactants, serving as oil-displacing agent systems, in the prior art are high in cost and not excellent in high temperature resistance and high-salt resistance are solved. According to the technical scheme, non-ionic surfactants as shown in the formula (1), single-hydrophilic-head-base anionic surfactants as shown in the formula (2) and double-hydrophilic-head-base anionic surfactants as shown in the formula (3) are adopted; R1, R2 and R3 are aliphatic groups of C4-C40 or aryl groups replaced by saturated and unsaturated hydroxy groups of C4-C30 straight chains or branched chains; Z1, Z2 and Z3 are -R01Y1, -R02Y2 and -R03Y3 respectively; R4, R5, R6 and R7 are independently selected from H, (CH2)pOH or (CH2)qCH3, p is equal to 2-4, and q is equal to 0-5. The problems are well solved, and the cathode non-mixed type oil displacement surfactants can be used for increasing the oil recovery rate in oilfield oil displacement. Please see the formulae in the specification.