Background technology
Polymer cement mortar is that synthetic latex is joined a kind of high-performance cement material that is mixed with in the sand-cement slurry, be widely used in building constructions both domestic and external field, reinforcing oil well field, and numerous areas such as railway, bridge, highway, reservoir river dykes and dams.Compare with conventional cement mortar, the polymer cement mortar good springiness, bending strength and tensile strength height, resistance to impact shock improves 10~15 times, and wear resistance improves 10~50 times; Water tolerance and good waterproof performance, its water-permeable only are 12% of conventional cement mortar; Chemical resistance increases, but the erosion of weak acid resistant, alkali, neutral salt and oils; Comparing with concrete, sand-cement slurry, ceramic tile, building stones, metal, glass and timber has very high bonding strength; Electrical insulating property improves, and thermal conductivity only is 30% of a conventional cement mortar, and thermal insulation and freeze-thaw resistance all make moderate progress; Contraction in the time of can reducing simultaneously the sand-cement slurry drying.
External exploitation cement latex and being used to improves the history of performance study existing five more than ten years of sand-cement slurry, and technology is also quite ripe.Latex anti-channeling, anticorrosion, improve aspect such as cement stone mechanical property and have remarkable advantages, existing abroad than widespread use, application at home is also more and more.At present, study both at home and abroad more, to use more latex products be styrene-butadiene latex, its heat resistance is good, can be used for the high temperature deep well well cementation.
Polymer emulsion bears extraneous factor its destructive ability is called STABILITY OF POLYMER EMULSION.Cement latex must have excellent chemical stability, makes the Ca of its ability cement stripping
2+And Al
3+Deng polyvalent cation; Simultaneously favorable mechanical stability to be arranged, higher mechanical shear stress when bearing the sand-cement slurry blending.For prevent that latex from flocculating in grout, need usually to add latex stabilizer, mainly be various tensio-active agents.At present, domestic and international research is mainly reflected in the exploitation of latex stabilizer, novel salt-resistant heatproof latex system, and how to select or develop supporting admixture such as water retaining, dispersion agent, retardant, defoamer etc. to form practical latex cement slurry system.
The example of research and development in domestic nearly ten years and successful Application also has a lot.As the patent No. is to have introduced among the CN03101262 to relate to the used high temperature anti-channeling latex cement admixture in oil field deep well well cementation field.Solved that the grout anti-channeling performance is poor, formation damage is serious, the problem of cementing quality difference.It is characterized in that the main raw material butadiene-styrene that uses, solid content has only 5~25 parts.So just exist problems such as polymerization production cost, transportation cost and raw materials cost height.In patents such as CN200610112832.8 and CN200610112833.2, in order to improve the performance of cement latex, adopted raw materials such as divinyl or isoprene to carry out the cement latex solid content height that polymerization obtains, performance is fair.But the reagent and additive in polymerization kind and the consumption of these two invention interpolations reach more than tens of kinds, and the polymkeric substance particle diameter is little, can cause viscosity of latex big like this, some problems such as system poor stability.Some producer or research unit just add auxiliary addition agent for improving certain point mass of latex as far as possible, and in fact effect is little, as long as make good use of necessary auxiliary agent, regulate polymerizing condition, reduce the interpolation kind and the consumption of reagent and additive in polymerization, will improve the stability and the quality product of latex.
Isoprene has the characteristic of natural rubber, main application is to prepare polyisoprene rubber by polymerization, or become butadiene-isoprene rubber, penta benzene rubber etc. with monomer copolymerizables such as divinyl, vinylbenzene, and as: the patent No. is to have introduced the method for utilizing isoprene to make tackiness agent and seal gum among the CN94110025.1; The patent No. is that the invention of CN200810034388.1 is the preparation method of isoprene emulsion and rubber; The patent No. is the new constituent that the invention of CN01104025.4, CN200710196328.5 etc. is tire and adhesive tape.Directly adopt isoprene actually rare as the report that rubber components prepares cement latex.
Summary of the invention
Technical problem to be solved by this invention provides a kind of cement synthetic latex, and traditional relatively styrene-butadiene latex has increased latex particle size, has reduced system viscosity and production cost, has strengthened the mechanical stability and the chemical stability of latex; Its preparation method is provided simultaneously.
Cement synthetic latex of the present invention, it is characterized in that it being vinylbenzene, isoprene and the 3rd monomeric multipolymer, the mass fraction of vinylbenzene and isoprene is 100 parts, wherein the mass fraction of isoprene is 40 parts~60 parts, the 3rd monomer is the composition of methacrylic acid and alkyl methacrylate, mass fraction is 3 parts~5 parts, and the mass ratio of methacrylic acid and alkyl methacrylate is 3: 2.
Described alkyl methacrylate is a kind of in methyl methacrylate, propyl methacrylate or the butyl methacrylate.
The cement of the present invention preparation method of synthetic latex may further comprise the steps:
(1) preparation of seed latex:
Deionized water is joined in the polymeric kettle, add vinylbenzene, isoprene, initiator, emulsifying agent and ionogen, polymerization temperature is 55 ℃~65 ℃, polymerization time is 10 hours~12 hours, polymerization is finished when solid content is 44~46wt%, vinylbenzene, the consumption of isoprene is respectively 1/10 of total consumption, initiator is 0.3~0.8% of this step polymerization single polymerization monomer vinylbenzene and an isoprene total mass, emulsifying agent is 1.5~2.0% of this step polymerization single polymerization monomer vinylbenzene and an isoprene total mass, and ionogen is 0.5~1.0% of this step polymerization single polymerization monomer vinylbenzene and an isoprene total mass;
(2) preparation of large grain size latex:
The seed latex of deionized water and step (1) preparation is joined in the polymeric kettle, add remaining vinylbenzene, isoprene and the 3rd monomer, initiator, emulsifying agent and ionogen, polymerization temperature is 55 ℃~65 ℃, polymerization time is 10 hours~12 hours, polymerization is finished when solid content is 44~46wt%, initiator is this step polymerization single polymerization monomer vinylbenzene, 0.3~0.8% of isoprene and the 3rd monomer total mass, emulsifying agent is this step polymerization single polymerization monomer vinylbenzene, 1.5~2.0% of isoprene and the 3rd monomer total mass, ionogen are this step polymerization single polymerization monomer vinylbenzene, 0.5~1.0% of isoprene and the 3rd monomer total mass;
(3) latex allotment:
Alkylphenol polyoxyethylene OP-10 is joined in the large grain size latex of step (2) preparation and allocate, the consumption of alkylphenol polyoxyethylene OP-10 is 2.0% of formula ratio vinylbenzene, isoprene and the 3rd a monomer total mass, mixes in 50 ℃~55 ℃.
Described initiator is a Potassium Persulphate, and emulsifying agent is a sodium lauryl sulphate, and ionogen is potassiumphosphate or sodium phosphate.
The total amount of described deionized water is 100 parts~150 parts.
The present invention adopts the emulsion polymerisation process preparation, based on isoprene and vinylbenzene, and suitably add a small amount of necessary other with it the 3rd monomer of copolymerization be prepared from, wherein isoprene be meant light by the by-product C5 fraction of petroleum cracking system ethene gained through taking off, take off weight, solvent oil extracting and the product that obtains.If the isoprene consumption is less than 40 parts, sand-cement slurry toughness and cohesive force after latex is mixed are bad; If isoprene is more than 60 parts, poor with the sand-cement slurry bonding force, rigidity is bad, and pressurization can distortion.
Adopt seed latex to prepare large grain size latex, improved latex solid content and with the effect that is mixed of cement, reduced the interpolation kind and the consumption of reagent and additive in polymerization in addition in the present invention as far as possible, reduced production cost, improved the stability of product.
Compared with prior art, beneficial effect of the present invention is as follows:
(1) adopt isoprene to substitute divinyl commonly used, cost of material is comparatively cheap, and performance is more excellent;
(2) the 3rd monomeric addings have improved the cohesive force of latex and cement;
(3) adopt seed latex to prepare large grain size latex, improved latex solid content and with the effect that is mixed of cement;
(4) with alkylphenol polyoxyethylene OP-10 latex is allocated, increased latex system stability and with the avidity of sand-cement slurry;
(5) the interpolation kind and the consumption of minimizing reagent and additive in polymerization have reduced the schedule of operation in the production process, have reduced raw materials cost, have also improved latex system stability simultaneously.
Embodiment
Below in conjunction with embodiment the present invention is described further.
Embodiment 1
A kind of cement synthetic latex, polymerization single polymerization monomer and massfraction: 50 parts of vinylbenzene, 50 parts of isoprene, 3 parts of methacrylic acids, 2 parts of methyl methacrylates, its preparation method may further comprise the steps:
(1) preparation of seed latex:
Deionized water is joined in the polymeric kettle for 13 parts, add 0.05 part of 5 parts of vinylbenzene, 5 parts of isoprene, 0.08 part of Potassium Persulphate, 0.15 part of sodium lauryl sulphate and potassiumphosphate, polymerization temperature is 60 ℃, and polymerization time is 11 hours, and polymerization is finished when solid content is 45.1wt%;
(2) preparation of large grain size latex:
The seed latex of 117 parts of remaining deionized waters and step (1) preparation is joined in the polymeric kettle, add 0.475 part of remaining vinylbenzene, isoprene and 3 parts of methacrylic acids, 2 parts of methyl methacrylates, 0.76 part of Potassium Persulphate, 1.425 parts of sodium lauryl sulphate and potassiumphosphate, polymerization temperature is 60 ℃, polymerization time is 11 hours, and polymerization is finished when solid content is 45.2wt%;
(3) latex allotment:
Alkylphenol polyoxyethylene OP-10 is joined in the large grain size latex of step (2) preparation and allocate, the consumption of alkylphenol polyoxyethylene OP-10 is 2.1 parts, mixes in 55 ℃.
Embodiment 2
A kind of cement synthetic latex, polymerization single polymerization monomer and massfraction: 60 parts of vinylbenzene, 40 parts of isoprene, 2.4 parts of methacrylic acids, 1.6 parts of butyl methacrylate, its preparation method may further comprise the steps:
(1) preparation of seed latex:
Deionized water is joined in the polymeric kettle for 10 parts, add 0.1 part of 6 parts of vinylbenzene, 4 parts of isoprene, 0.03 part of Potassium Persulphate, 0.2 part of sodium lauryl sulphate and potassiumphosphate, polymerization temperature is 65 ℃, and polymerization time is 10.5 hours, and polymerization is finished when solid content is 44.8wt%;
(2) preparation of large grain size latex:
The seed latex of 90 parts of remaining deionized waters and step (1) preparation is joined in the polymeric kettle, add 0.94 part of remaining vinylbenzene, isoprene and 2.4 parts of methacrylic acids, 1.6 parts of methyl methacrylates, 0.282 part of Potassium Persulphate, 1.88 parts of sodium lauryl sulphate and potassiumphosphate, polymerization temperature is 65 ℃, polymerization time is 10.5 hours, and polymerization is finished when solid content is 45.6wt%;
(3) latex allotment:
Alkylphenol polyoxyethylene OP-10 is joined in the large grain size latex of step (2) preparation and allocate, the consumption of alkylphenol polyoxyethylene OP-10 is 2.08 parts, mixes in 50 ℃.
Embodiment 3
A kind of cement synthetic latex, polymerization single polymerization monomer and massfraction: 40 parts of vinylbenzene, 60 parts of isoprene, 1.8 parts of methacrylic acids, 1.2 parts of propyl methacrylates, its preparation method may further comprise the steps:
(1) preparation of seed latex:
Deionized water is joined in the polymeric kettle for 15 parts, add 0.08 part of 4 parts of vinylbenzene, 6 parts of isoprene, 0.05 part of Potassium Persulphate, 0.15 part of sodium lauryl sulphate and sodium phosphate, polymerization temperature is 55 ℃, and polymerization time is 12 hours, and polymerization is finished when solid content is 45.6%wt;
(2) preparation of large grain size latex:
The seed latex of 135 parts of remaining deionized waters and step (1) preparation is joined in the polymeric kettle, add 0.744 part of remaining vinylbenzene, isoprene and 1.8 parts of methacrylic acids, 1.2 parts of methyl methacrylates, 0.465 part of Potassium Persulphate, 1.395 parts of sodium lauryl sulphate and sodium phosphate, polymerization temperature is 55 ℃, polymerization time is 12 hours, and polymerization is finished when solid content is 45.8wt%;
(3) latex allotment:
Alkylphenol polyoxyethylene OP-10 is joined in the large grain size latex of step (2) preparation and allocate, the consumption of alkylphenol polyoxyethylene OP-10 is 2.06 parts, mixes in 55 ℃.
Embodiment 4
A kind of cement synthetic latex, polymerization single polymerization monomer and massfraction: 45 parts of vinylbenzene, 55 parts of isoprene, 3 parts of methacrylic acids, 2 parts of methyl methacrylates, its preparation method may further comprise the steps:
(1) preparation of seed latex:
Deionized water is joined in the polymeric kettle for 12 parts, add 0.1 part of 4.5 parts of vinylbenzene, 5.5 parts of isoprene, 0.03 part of Potassium Persulphate, 0.2 part of sodium lauryl sulphate and sodium phosphate, polymerization temperature is 65 ℃, and polymerization time is 11 hours, and polymerization is finished when solid content is 45.3wt%;
(2) preparation of large grain size latex:
The seed latex of 108 parts of remaining deionized waters and step (1) preparation is joined in the polymeric kettle, add 0.95 part of remaining vinylbenzene, isoprene and 3 parts of methacrylic acids, 2 parts of methyl methacrylates, 0.285 part of Potassium Persulphate, 1.9 parts of sodium lauryl sulphate and sodium phosphate, polymerization temperature is 65 ℃, polymerization time is 11 hours, and polymerization is finished when solid content is 45.5%;
(3) latex allotment:
Alkylphenol polyoxyethylene OP-10 is joined in the large grain size latex of step (2) preparation and allocate, the consumption of alkylphenol polyoxyethylene OP-10 is 2.1 parts, mixes in 50 ℃.
Comparative example 1
Isoprene among the embodiment 1 is replaced with divinyl, and solid content is that seed latex polymerization in 44.2% o'clock is finished, and the large grain size latex polymerization is finished when solid content is 45.1%, and all the other are all as embodiment 1.
Comparative example 2
Change the preparation method among the embodiment 1 into not seed addition latex, one step was finished polymerization, deionized water is joined in the polymeric kettle for 130 parts, add 0.525 part of 50 parts of vinylbenzene, 50 parts of isoprene, 0.84 part of Potassium Persulphate, 1.575 parts of sodium lauryl sulphate and potassiumphosphate, polymerization temperature is 60 ℃, polymerization time is 11 hours, and polymerization is finished when solid content is 44.8wt%.
Comparative example 3
The mass fraction of the polymerization single polymerization monomer among the embodiment 1 is changed into: 70 parts of vinylbenzene, 30 parts of isoprene, 3 parts of methacrylic acids, 2 parts of methyl methacrylates, other conditions are constant, its preparation method such as embodiment 1, solid content is that seed latex polymerization in 44.8% o'clock is finished, and the large grain size latex polymerization is finished when solid content is 45.2%.
Comparative example 4
The mass fraction of the polymerization single polymerization monomer among the embodiment 1 is changed into: 30 parts of vinylbenzene, 70 parts of isoprene, 3 parts of methacrylic acids, 2 parts of methyl methacrylates, other conditions are constant, its preparation method such as embodiment 1, solid content is that seed latex polymerization in 44.2% o'clock is finished, and the large grain size latex polymerization is finished when solid content is 44.7%.
Cement latex to above preparation is tested, and the employing standard and the performance of surveying see Table 1.
Table 1 cement gel milkiness can compare
Title |
Particle diameter nm |
Viscosity mPa.s |
Mechanical stability % |
Chemical stability Ca
2+%
|
Embodiment 1 |
413.5 |
28.4 |
0.002 |
0.005 |
Embodiment 2 |
358.6 |
25.8 |
0.008 |
0.002 |
Embodiment 3 |
381.0 |
32.0 |
0.013 |
0.011 |
Embodiment 4 |
326.9 |
37.1 |
0.022 |
0.080 |
Comparative example 1 |
253.5 |
23.0 |
0.006 |
0.062 |
Comparative example 2 |
245.3 |
49.4 |
0.004 |
0.002 |
Comparative example 3 |
323.6 |
29.7 |
0.067 |
0.061 |
Comparative example 4 |
369.2 |
87.6 |
0.500 |
0.397 |
Testing method |
Turbidimetry |
GB2956-82 |
SH/T1151-92 |
SH/T1608-95 |
As can be seen from Table 1, adopt the cement latex of seed latex preparation, particle diameter is general big, and viscosity of latex is also more moderate.This is because adopt the bigger isoprene of molar mass to substitute less divinyl and the poly-again effect of employing seed latex, has increased latex particle size, has reduced system viscosity, has strengthened mechanical stability and chemical stability.As can be seen, if the consumption of isoprene is too many, though latex particle size is bigger, latex system viscosity also becomes greatly from comparative example 4, and while mechanical stability and chemical stability be variation also.
Each 10 parts in the cement latex and the sand-cement slurry of the foregoing description 1~4 and comparative example 1~2 preparation are mixed, compare with the plain cement mortar, The performance test results sees Table 2.
Table 2 cement latex and sand-cement slurry are mixed the back product performance relatively
As can be seen from Table 2, add the polymer cement mortar of preparing behind 10 parts of products of the present invention, can significantly increase bonding strength, folding strength, ultimate compression strength and the shock strength of sand-cement slurry, function and shrinking percentage with water proof anti-seepage are little.Not only improved stability but also stronger with the cohesive force of cement, performance is better.Show that through using producer's test and constructing in a large number these product performance are good, reach the quality standard of national regulation.