CN102766305B - High-strength heat resisting polystyrene composite crosslinking microsphere material and preparation method thereof - Google Patents
High-strength heat resisting polystyrene composite crosslinking microsphere material and preparation method thereof Download PDFInfo
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- CN102766305B CN102766305B CN201210294335.XA CN201210294335A CN102766305B CN 102766305 B CN102766305 B CN 102766305B CN 201210294335 A CN201210294335 A CN 201210294335A CN 102766305 B CN102766305 B CN 102766305B
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Abstract
The invention discloses a high-strength heat resisting polystyrene composite crosslinking microsphere material and a preparation method thereof. A microsphere comprises an organic and inorganic composite crosslinking structure unit. The preparation method includes that styrene and divinyl benzene are used as a basic monomer of a crosslinking frame, alkene with a lateral group containing an alcoxyl silicon structure is used as an auxiliary crosslinking function monomer, water is used as a medium, and crosslinking polymer microsphere with a composite three-dimensional net structure by using suspension polymerization process, wherein the size of the microsphere is adjustable. The preparation method is characterized in that in a suspension polymerization reaction process, the alcoxyl silicon structure and divinyl benzene respectively have crosslinking reaction synchronously to form net-shaped crosslinking structures with different essences so as to improve the strength and heat resistance of polystyrene microsphere of an organic crosslinking structure. The high-strength heat resisting polystyrene composite crosslinking microsphere material is simple in process, smooth in microsphere surface, has good lubricating and anti-drag functions, has high strength and heat resistance, and is applicable to situations of large pressure or high temperature, such as the fields of petroleum or crude oil extraction and liquid crystal gas control.
Description
Technical field
The invention belongs to field of polymer material preparing technology, relate to a kind of micro-sphere material and preparation method thereof, specifically, is the heat-resisting polystyrene composite crosslinked microsphere of a kind of high strength (withstand voltage) material and preparation method thereof.
Background technology
Along with the continuous expansion in Oil Exploration in China field, drilling strata is increasingly sophisticated, and drilling depth constantly increases, and all kinds of lock of tool drilling frequently occur.In drilling fluid, adding highly-efficient lubricant is to reduce down hole problem, reduces the frictional resistance between the borehole wall and drilling tool, drilling tool and sleeve pipe, improves drilling speed, the conventional means that reduces drilling tool moment of torsion, reduces drilling tool wearing and tearing, avoids lock of tool drilling to occur.Although in recent years, the research of lubricant for drilling fluid has made great progress, but still has some problems: as cause drilling fluid foaming, and drilling fluid viscosity, shear force increase, and are unfavorable for on-the-spot property of drilling fluid maintenance processing; Lubricity is poor, and extreme pressure film toughness is low, is difficult to meet the requirement under the high wall pressure condition of orientation well; Fluorescence grade is high, disturbs geological logging etc.
At present conventional drill-in fluid is with lubricator mainly divided into two kinds of liquid lubricant and solid lubricants, and wherein solid lubricant is subject to again people's favor day by day because having high loading, the advantage such as corrosion-resistant.Solid lubricant spherical-like morphology effect in drilling fluid is better.In various factors effect, second imbeds in mud cake microballoon, forms the miniature upholder between mud cake and drilling tool.Like this, drilling fluid just can enter the gap between mud cake and drilling tool, avoids forming pressure reduction in drill string both sides, makes pressure differential sticking be difficult for occurring.The bead of partly imbedding in mud cake plays micro-bearing between the borehole wall and drilling tool, and moment of torsion is reduced greatly.In addition, be suspended in the microballoon in drilling fluid, make the friction between drill string and drilling fluid become rolling from slip to a certain extent, drilling fluid frictional resistance is reduced greatly.
The more solid lubricant of application mainly contains graphite, molybdenumdisulphide, resin microsphere, glass microballon etc. at present.Graphite Powder 99 as lubricant have high temperature resistance, without fluorescence, fall frictional resistance successful, dosage little, to features such as property of drilling fluid have no adverse effects, but conventional graphite and molybdenumdisulphide are Powdered, easily waft at fluid surface, therefore availability is low, waste resource and contaminate environment.Prove that at present glass pellet can reduce moment of torsion and resistance.But glass microballon is crisp, the pressure can bear is little, and percentage of damage is high, and rate of small round spheres is also lower.Resin microsphere is the more efficient solid lubricant for well drilling liquid of one, have nontoxic, without the advantage such as fluorescence, recoverable, but the thermotolerance of traditional common virgin resin material bad, the heat producing in drilling process easily makes resin generation softening transform.And under the extruding or beating of drilling rod, having the possibility of destruction, insufficient strength is high, therefore needs to have higher intensity.The drilling fluid microballoon lubricant simultaneously with better thermotolerance and intensity, will can play huge pushing effect to the development of Petroleum Exploration Engineering.
The suspension process preparation method of tradition polystyrene resin microballoon is: by vinylbenzene and Vinylstyrene blending dispersion in water, under initiator effect, carry out suspension polymerization in 65 ~ 95 DEG C of scopes and generate copolymer resins, then obtain copolymer resins bead through washing, be dried, sieving.Its weak point is that intensity, thermotolerance are not high enough, and work-ing life is short.
Patent CN200910180694.0 discloses a kind of preparation method of solid lubricant microspheres for drilling fluid, it is the method for utilizing physical mixed, adopt and in monomer, add layered inorganic filler, polymer chain in resin after polymerization can be intercalation between inorganic materials, expect by inorganic materials lamella, the restriction of polymer segment motion to be improved the thermal characteristics of matrix material.But in this patent, do not provide relevant data message.Its paper of delivering (Fig. 6 in paper) shows: with do not add polynite ratio, the thermotolerance of complex microsphere before 375 DEG C on the contrary to some extent decline; In the method, directly adding of inorganics, makes monomer droplet be difficult for being broken up, and causes the particle diameter of composite particles larger; Polynite exists with heterogeneous state in polymkeric substance, and due to the inhibition on nano imvite surface, a small amount of monomer and oligopolymer that made its surface adsorption, causes matrix material ball surface irregularity, has indenture, rough, cause lubrication drag reduction effect bad; And the density of inorganics is also much bigger than organic constituent; Because inorganic sheet needs pre-treatment, increase operation, and be distributed in water, cause difficulty to polymerization process.(matrix material journal, 2010,27 (3): 36 ~ 42).Existing synthetic technology thermotolerance and undercapacity, the defects such as lubrication drag reduction poor performance, complex procedures.
Summary of the invention
The technical problem to be solved in the present invention is to provide the simple polystyrene composite crosslinked microsphere of a kind of technique material and preparation method thereof, to improve intensity and the thermotolerance of microballoon, microsphere features smooth surface degree and particle size uniformity, make it have better lubrication drag reduction function, improves work-ing life.
In order to solve the problems of the technologies described above, technical scheme of the present invention is as follows.
High strength heat resistant polystyrene composite crosslinked microsphere material provided by the invention, comprises styrene monomer unit and crosslink unit, and its crosslink unit comprises organic crosslinking structure I and inorganic crosslinking structure I I, and its structure is as follows:
。
For styrene monomer unit and crosslink unit, its any unit can be connected with xenogenesis structural unit in swash position or be connected with homogenous configuration unit, and another structural unit number between any two adjacent homogenous configuration unit is not etc.
Inorganic crosslinking structure I I is formed by the auxiliary crosslinked function monomer unit containing silica structure, in II-R is methyl, X is connector element, this connector element can be covalent linkage ,-COO-and-COO-R
1-in any, should-COO-R
1-in R
1for the alkyl being formed by carbon and hydrogen.
Microspherulite diameter scope is 0.1 ~ 0.8 mm.
The preparation method of high strength heat resistant polystyrene composite crosslinked microsphere material provided by the invention, comprises the following steps:
1) dispersion agent 0.01-2.0 part and water dissolution inhibitor 0-2 part are dissolved in to reactor at 40 DEG C in 100 parts of deionized waters, pass into nitrogen protection, stir and be made in advance uniform aqueous phase composition solution;
2), by vinylbenzene 25-50 part, Vinylstyrene 0-50 part, be mixed into even oil phase composition and add in the reactor in step 1) containing the auxiliary crosslinked function monomer 0-20 part of silicon structure and oil-soluble initiator 0.01-2.0 part, stir 0.2 ~ 2 hour;
3) be heated to 75 DEG C, continue to pass into nitrogen, react 0.5 ~ 5 hour;
4) be heated to 95 DEG C, continue to pass into nitrogen, react slaking in 0.5 ~ 5 hour;
5) cooling finishes reaction, to processing such as polymerisate polystyrene composite crosslinked microsphere wash, filters, is dried.
Crosslinked function monomer described in above preparation method is CH
2=C (CH
3) COO (CH
2)
3-Si-(OCH
3)
3, CH
2=C (CH
3) COO (CH
2)
3-Si-(OCH
2cH
3)
3or the two mixture.
Dispersion agent described in preparation method is polyvinyl alcohol.
Water dissolution inhibitor described in step 1) is sodium salt.
Step 2) described in oil-soluble initiator be superoxide.
The present invention has beneficial effect.High strength heat resistant polystyrene composite crosslinked microsphere material preparation method technique of the present invention is simple, do not use inorganic raw material composition and can form the structure of similar inorganics, without other special dispersion steps of the ultrasonic grade of process, can in suspension polymerization process, utilize alcoxyl silicon structure to synchronize with Vinylstyrene crosslinking reaction separately occurs, form inorganic, the cross-linked network of organic composite, thereby improve intensity and the thermotolerance of polystyrene microsphere of the present invention, and stereoscan photograph shows microsphere features smooth surface, there is better lubrication drag reduction function, be applicable to the occasion that pressure is large or temperature is high.
Brief description of the drawings
Below in conjunction with accompanying drawing, the specific embodiment of the present invention is described in further detail.
The scanning electron microscope (SEM) photograph that Fig. 1 a is the polymer microsphere that obtains by the embodiment of the present invention 1.
The scanning electron microscope (SEM) photograph that Fig. 1 b is the polymer microsphere that obtains by the embodiment of the present invention 2.
Fig. 2 is by the embodiment of the present invention 2 and the prepared polymer microsphere size distribution comparison diagram of embodiment 1.
The infrared spectra spectrogram that Fig. 3 a is the polymer microsphere that obtains by the embodiment of the present invention 1.
The infrared spectra spectrogram that Fig. 3 b is the polymer microsphere that obtains by the embodiment of the present invention 2.
Fig. 4 is by thermotolerance (thermogravimetric) the comparative analysis figure of the embodiment of the present invention 2 and the prepared polymer microsphere of embodiment 1.
Embodiment
Following instance is to further illustrate of the present invention, but these embodiment are not used for limiting the scope of the invention.
Embodiment 1
100 parts of deionized waters, 0.125 part of polyvinyl alcohol and 1 part of sodium-chlor are added to logical nitrogen in reactor; stirring and dissolving at 40 DEG C; by 21 parts of vinylbenzene; 4 parts of Vinylstyrenes; 0.2 part of benzoyl peroxide is mixed into oil phase composition and joins in reactor, maintains 40 DEG C and continues logical nitrogen gas stirring 0.5 hour, is heated to 75 DEG C; logical nitrogen protection reaction 4 hours, is warming up to 95 DEG C of nitrogen protection reactions 2 hours.Cooling finishes reaction, washs, filters, dries, sieves, and obtains the copolymerization microsphere of 0.1-0.8 mm.
Its stereoscan photograph of microballoon of preparing gained by this embodiment is as shown in Figure 1a: size is 0.1-0.8mm, microsphere features smooth surface.Prepared the polystyrene composite crosslinked microsphere of gained by this embodiment, with method of sieving test the concrete distribution situation of microspherulite diameter size as shown in Figure 2, wherein X-coordinate is microsphere diameter, unit is millimeter (mm), the per-cent of the weight of the microballoon that ordinate zou is respective diameters in gross weight; As shown in Figure 4, in figure, X-coordinate is temperature to thermogravimetric analysis figure, unit DEG C, and ordinate zou accounts for the per-cent of starting weight for testing sample (microballoon) weight at this temperature.
Embodiment 2
100 parts of deionized waters, 0.125 part of polyvinyl alcohol and 1 part of sodium-chlor are added to logical nitrogen in reactor; stirring and dissolving at 40 DEG C; by 21 parts of vinylbenzene; 4 parts of Vinylstyrenes, 2 parts of γ-(methacryloxypropyl) propyl trimethoxy silicanes, 0.2 part of benzoyl peroxide is mixed into oil phase composition and joins in reactor; maintain 40 DEG C and continue logical nitrogen gas stirring 0.5 hour; be heated to 75 DEG C, logical nitrogen protection reaction 4 hours, is warming up to 95 DEG C of nitrogen protection reactions 2 hours.Cooling finishes reaction, washs, filters, dries, sieves, and obtains the copolymerization microsphere of 0.1-0.8mm.
Prepared the polystyrene composite crosslinked microsphere (resin microsphere) of gained by this embodiment, its stereoscan photograph as shown in Figure 1 b: size is 0.1-0.8mm, microsphere features smooth surface.Prepared the polystyrene composite crosslinked microsphere of gained by this embodiment, by method of sieving test the concrete distribution situation of microspherulite diameter size as shown in Figure 2, wherein X-coordinate is microsphere diameter, unit is millimeter (mm), the per-cent of the weight of the microballoon that ordinate zou is respective diameters in gross weight; As shown in Figure 4, in figure, X-coordinate is temperature to thermogravimetric analysis figure, unit DEG C, and ordinate zou accounts for the per-cent of starting weight for testing sample (microballoon) weight at this temperature.
Compared with embodiment 2 microballoon prepared with embodiment 1, obtain infrared spectra contrast spectrogram as shown in Figure 3 according to Infrared spectroscopy, in Fig. 3, a is the infrared spectra of embodiment 1, and in Fig. 3, b is the infrared spectra of embodiment bis-, and X-coordinate is wave number, the cm of unit
-1, ordinate zou is per-cent transmitance.Result shows: in embodiment 2, by adding 2 parts of γ-(methacryloxypropyl) propyl trimethoxy silicane, formed silica silicon inorganic crosslinking network in polymerization process.Add the present invention γ used-(methacryloxypropyl) propyl trimethoxy silicane as after auxiliary crosslinked function monomer, its abrasion hardness of the microballoon of preparation obviously increases, and thermotolerance is obviously improved, and thermotolerance as shown in Figure 4.
Embodiment 3
100 parts of deionized waters, 2 parts of polyvinyl alcohol and 2 parts of sodium-chlor are added to logical nitrogen in reactor; stirring and dissolving at 40 DEG C; by 21 parts of vinylbenzene; 0 part of Vinylstyrene; 10 parts of γ-(methacryloxypropyl) propyl-triethoxysilicanes; the mixed solution of 0.05 part of benzoyl peroxide and 0.05 part of peroxidation 2 ethyl hexanoic acid tert-butyl ester is mixed into oil phase composition and joins in reactor; maintain 40 DEG C and continue logical nitrogen gas stirring 0.5 hour; be heated to 75 DEG C; logical nitrogen protection reaction 4 hours, is warming up to 95 DEG C of nitrogen protection reactions 2 hours.Cooling finishes reaction, washs, filters, dries, sieves, and obtains the copolymerization microsphere of 0.1-0.8 mm.It is identical that the microballoon of preparing gained by this embodiment and embodiment 2 prepare thus obtained microsphere structure, has same premium properties.
Embodiment 4
100 parts of deionized waters, 0.01 part of polyvinyl alcohol and 0 part of sodium-chlor are added to logical nitrogen in reactor; stirring and dissolving at 40 DEG C; by 21 parts of vinylbenzene; 0 part of Vinylstyrene; 10 parts of γ-(methacryloxypropyl) propyl trimethoxy silicanes; 10 parts of γ-(methacryloxypropyl) propyl-triethoxysilicanes; 2 parts of benzoyl peroxides are mixed into oil phase composition and join in reactor; maintain 40 DEG C and continue logical nitrogen gas stirring 0.5 hour; be heated to 75 DEG C; logical nitrogen protection reaction 4 hours, is warming up to 95 DEG C of nitrogen protection reactions 2 hours.Cooling finishes reaction, washs, filters, dries, sieves, and obtains the copolymerization microsphere of 0.1-0.8 mm.It is identical that the microballoon of preparing gained by this embodiment and embodiment 2 prepare thus obtained microsphere structure, has same premium properties.
Claims (8)
1. a high strength heat resistant polystyrene composite crosslinked microsphere material, comprises styrene monomer unit and crosslink unit, it is characterized in that described crosslink unit comprises organic crosslinking structure I and inorganic crosslinking structure I I,
Described inorganic crosslinking structure I I is formed by the auxiliary crosslinked function monomer unit containing silica structure, in II-R is methyl, X is connector element; Described connector element X is-COO-(CH
2)
3-.
2. a kind of high strength heat resistant polystyrene composite crosslinked microsphere material as described in claim 1, it is characterized in that: described styrene monomer unit all can be connected with xenogenesis structural unit in swash position or be connected with homogenous configuration unit with crosslink unit, another structural unit number between any two adjacent homogenous configuration unit is not etc.
3. a kind of high strength heat resistant polystyrene composite crosslinked microsphere material as described in claim 1, is characterized in that: the particle size range of described microballoon is 0.1 ~ 0.8 mm.
4. the preparation method of high strength heat resistant polystyrene composite crosslinked microsphere material as described in claim 1, comprises the following steps:
1) dispersion agent 0.01-2.0 part and water dissolution inhibitor 0-2 part are dissolved in to reactor at 40 DEG C in 100 parts of deionized waters, pass into nitrogen protection, stir and be made in advance uniform aqueous phase composition solution;
2) by vinylbenzene 25-50 part, Vinylstyrene 0-50 part, be mixed into even oil phase composition containing the auxiliary crosslinked function monomer 0-20 part of silicon structure and oil-soluble initiator 0.01-2.0 part, and add in the reactor in step 1), stir 0.2 ~ 2 hour;
3) be heated to 75 DEG C, continue to pass into nitrogen, react 0.5 ~ 5 hour;
4) be heated to 95 DEG C, continue to pass into nitrogen, react slaking in 0.5 ~ 5 hour;
5) cooling finishes reaction, to processing such as polymerisate polystyrene composite crosslinked microsphere wash, filters, is dried;
It is characterized in that step 2) in oil phase composition in add the auxiliary crosslinked function monomer of silica structure.
5. preparation method as claimed in claim 4, is characterized in that: described crosslinked function monomer is CH
2=C (CH
3) COO (CH
2)
3-Si-(OCH
3)
3, CH
2=C (CH
3) COO (CH
2)
3-Si-(OCH
2cH
3)
3or the two mixture.
6. preparation method as claimed in claim 4, is characterized in that: the dispersion agent described in step 1) is polyvinyl alcohol.
7. preparation method as claimed in claim 4, is characterized in that: the water dissolution inhibitor described in step 1) is sodium salt.
8. preparation method as claimed in claim 4, is characterized in that: step 2) described in oil-soluble initiator be superoxide.
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| CN101705079A (en) * | 2009-10-28 | 2010-05-12 | 无锡润鹏复合新材料有限公司 | Method for preparing novel solid lubricant microspheres for drilling fluid |
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