GRANULAR MAGNETIC POLYMER AND GROUTING MIXTURE FOR CEMENTING OF CASING COLUMNS BASED ON MAGNETIC POLYMER Russian patent published in 2019 - IPC C09K8/46 C09K8/467 E21B33/138 C04B18/02 C04B14/38 H01F1/04 

FIELD: composite materials.

SUBSTANCE: invention relates to production of composite materials, in particular to production of magnetically active elastic composites (polymers), intended for production of cement mixture controlled by magnetic field, as well as to methods of fixing gas-oil-water wells during cementing of casing strings at different stages of construction and operation of well, if necessary providing extremely low values of fluid permeability of plugging material behind production string. Technical result is achieved by the fact that disclosed is a granular magnetic polymer for making composite materials in cement mixture elements, consisting of an elastic polymer matrix, a magnetic filler and a cement additive, wherein the polymer matrix used is natural and/or synthetic rubber, magnetic filler with particle size in range of 1–100 mcm is magnetic powders of iron-neodymium boron NdFeB, and/or magnetite Fe₃O₄, and/or iron powder, and/or magnetic alloys of iron – iron-cobalt, and/or iron-nickel, and/or permalloy alloy, portland cement is used as cement additive at following content of components, wt h: magnetic filler 1–75, portland cement 1–75, polymer matrix – 100 and additionally carbon or basalt fibers – 0–50, to produce granules with the following characteristics: density of magnetic polymer 2–3.5 g/cm³, elasticity 0.5–30 MPa, residual magnetization 1–30 Gs·cm³/g with operating temperature from -50 to + 200 °C.

EFFECT: technical result consists in producing a magnetic polymer and grouting mixture containing a magnetic polymer, characterized by the following characteristics: reduced cracks of the frozen solution, increased elasticity, increased adhesion with the casing string, namely improved operational properties of the cement solution consists in reduction of cracks, increase in elasticity, increasing adhesion with a casing string due to addition of a complex polymer additive in form of polymer particles into the cement solution, including magnetic particles and cement particles.

4 cl, 9 dwg, 3 tbl