With the hydrogel microsphere is the method that template prepares hollow microsphere
Technical field
The present invention relates to the hydrogel microsphere is the method that template prepares hollow microsphere.
Background technology
The polymeric hollow microballoon of nanometer and submicron-scale had received increasing concern in the last few years, and they have more wide application prospect at aspects such as cosmetics, coating, printing ink, biological medicine and paper manufacturing industry.Succeeding in developing of hollow microsphere is one of three big achievements that change over nearly 40 years coatings industry.Because the hollow-core construction of hollow-particle, the refraction index of shell high polymer and kernel air exists bigger difference, repeatedly refraction when passing through hollow microsphere, light takes place, so hollow microsphere has effective covering, can replace expensive titanium dioxide as Chinese white, escapable cost improves the stain resistance and the washability of coating.The water color ink that has mixed the hollow microsphere emulsion can obtain full, effect that covering power is good bright in luster after printing.Another important use of polymer hollow particles is as microcapsules, and portion's encapsulation function compound is made the macromolecular material with slow-release function within it.In addition, because the shell of hollow microsphere is selected the higher macromolecular material of vitrification point usually for use, they can be used as functional stuffing again, are used for the modification of high molecular toughness reinforcing, enhancing, insulation, adiabatic aspect.
The method for preparing at present hollow-particle is many, mainly contains: self-assembly method, template and emulsion method etc.Self-assembly method is utilize the block polymer segment amphiphilic, can self assembly in selective solvent forms the micella of different shape, comprises sphere, bar-shaped, vesica shape etc., carries out shell crosslinked again and remove stoning partly making the stable hollow structure particulate.The particle that this method obtains can have nanostructured and more regular nucleocapsid form, but the synthetic more complicated of block copolymer, self assembling process carries out in organic solvent usually, and the variation to system concentration, composition is relatively more responsive, and small amount of impurities just can influence self assembling process and form lopsided particle.The method that template prepares hollow microsphere is the surface coverage polymer shell in template particles, and then removes template and form hollow microsphere.Template selects for use charged colloidal particle and inorganic particulate (as silica, calcium carbonate etc.) to be template usually, selecting polyelectrolyte for use is shell, method by self assembly layer by layer makes the polyelectrolyte template particles surface realization absorption successively that has opposite charges, when the shell polymer thickness reaches desirable value the template particles of inside is removed.But this method needs long time and purifying repeatedly, and efficient is lower.In addition, template need remove template with strong acid or highly basic usually, and is all harmful to human body and environment.For example, Chinese patent (CN1303140C) has provided a kind of preparation method of polymer hollow particles, is template with the inorganic matter nano particle, at its surface grafting one layer of polymeric, by strong acid the inorganic matter nano particle is removed then.Emulsion method is to utilize seeded emulsion polymerization or the technology of water/oil/aqueous phase separation prepares the method with hollow structure particle, and most typical is the soda acid swelling method.At first obtaining the outside with seeded emulsion polymerization is that high glass transition temperature polymer shell inside is the particle of the nucleocapsid structure of polyelectrolyte, in acid or aqueous slkali, be warmed up to the softening point of shell polymer then, shell polymer softening causes external solution can enter particle inside to make particle generation swelling and neutralization dissolve polyelectrolyte as nuclear, the final particle that obtains to have hollow structure.This method step is many, the time is long, and process conditions such as pH value, temperature need relatively stricter control in last soda acid is handled.
Summary of the invention
The objective of the invention is provides a kind of easy, that need not remove template, eco-friendly method for preparing polymer or inorganic compound hollow microsphere in order to overcome the defective that above-mentioned prior art exists.
The objective of the invention is to be achieved through the following technical solutions: at first preparation has the hydrogel microsphere of electric charge, and it is by the crosslinked water-soluble polymer microballoon that abundant swelling forms in water, and equilibrium water absorption is the tens of to hundreds of times of dry weight; With the hydrogel microsphere is template, with the surfactant of oppositely charged with it hydrogel surface is handled, make the hydrogel microsphere surface form hydrophobic micella layer, then hydrophobic monomer is adsorbed in this hydrophobic micella layer and polymerization, the formation shell is a hydrophobic polymer, and internal layer is the core-shell particles of hydrogel microsphere; Perhaps by adsorbing inorganic compound on the hydrogel microsphere surface, the formation shell of formation is an inorganic compound, and internal layer is the core-shell particles of hydrogel microsphere.Above-mentioned core-shell particles is in the process of drying, inner hydrogel microsphere dehydration, contraction, just form microballoon with hollow structure, its reason is: one, hydrogel microsphere can reduce tens of to hundreds of times from solvent swelling state volume to the drying and dehydrating state time, therefore, core-shell particles is when drying, and significant volume contraction takes place its inner hydrogel microsphere, thereby forms hollow-core construction.Two, outer shell is selected higher polymer or the inorganic compound of vitrification point, and when shell thickness was enough big, shell structurre still can keep when the dry contraction of internal water gel micro-ball, do not deform, thus the formation of assurance nucleocapsid structure.
Of the present invention is the method that template prepares hollow microsphere with the hydrogel microsphere, and concrete steps are as follows:
1) with emulsion or the synthetic charged hydrogel microsphere of inverse emulsion polymerization method
Emulsion polymerisation process is as follows: with monomer N-N-isopropylacrylamide, crosslinking agent N, N '-methylene-bisacrylamide, surfactant, ionic water-soluble monomer, initiator system and water are according to weight ratio 1: (0.001~0.1): (0~0.05): (0.001~0.2): (0.001~0.05): (10~200) join in the reactor, feed inert gas, 50~90 ℃ of reactions down, obtain hydrogel microsphere, with dialysis or method of pumping filtration separation and purification;
The inverse emulsion polymerization method is as follows: with mixture, the crosslinking agent N of ionic water-soluble monomer or ionic and non-ionic water-soluble monomer, N '-methylene-bisacrylamide, surfactant, initiator system, water and oil phase solvent are according to weight ratio 1: (0.001~0.1): (0.01~0.5): (0.001~0.1): (1~20): (20~200) join in the reactor, feed inert gas, 50~90 ℃ of reactions down, obtain hydrogel microsphere, with dialysis or method of pumping filtration separation and purification;
2) hydrogel microsphere is dispersed in the water again, forms hydrogel microsphere suspension, add the surfactant with the hydrogel microsphere oppositely charged then, the weight ratio of surfactant and hydrogel microsphere dry weight is (0.01~0.5): 1;
3) in step 2) add hydrophobic monomer and initiator system in the resulting hydrogel microsphere suspension, weight ratio is the hydrogel dry weight: hydrophobic monomer: initiator system is 1: (1~50): (0.01~0.6), carry out polymerisation, obtain the inner hydrogel microsphere that is, skin is the core-shell particles of hydrophobic polymer; Perhaps in step 2) add acid or base catalyst in the resulting hydrogel microsphere suspension and add silica or titanium dioxide precursor, weight ratio is the hydrogel microsphere dry weight: catalyst: silica or titanium dioxide precursor=1: (0.01~0.05): (5~50), react, obtain the inner hydrogel microsphere that is, skin is the core-shell particles of inorganic matter shell;
4) with core-shell particles vacuum drying or freeze drying, obtain hollow microsphere.
Among the present invention, said initiator system can be potassium peroxydisulfate, ammonium persulfate, benzoyl peroxide, hydrogen peroxide, azodiisobutyronitrile, ABVN, 4,4 '-azo two (4-cyanopentanoic acid) and N, in N '-azo diisobutyl amidine hydrochloride one or several, or the mixture of potassium peroxydisulfate or ammonium persulfate and sulphite, or the mixture of potassium peroxydisulfate or ammonium persulfate and bisulfites, or the mixture of hydrogen peroxide and frerrous chloride or ascorbic acid.
Among the present invention, said oil phase solvent can be cyclohexane, n-hexane, normal heptane, benzene, dimethylbenzene, atoleine, white oil, kerosene or diesel oil.Inert gas can be nitrogen, argon gas, helium or carbon dioxide.
Among the present invention, said ionic water-soluble monomer is cationic or the anionic monomer, wherein, cationic monomer can be one or more mixtures in methylacryoyloxyethyl trimethyl ammonium chloride, methylacryoyloxyethyl trimethylammonium bromide, styrene benzyltrimethylammonium chloride, methacrylic benzyl ammonium chloride, methacrylic benzyl ammonium bromide, pi-allyl trimethyl ammonium chloride, pi-allyl trimethylammonium bromide and the methylacryoyloxyethyl dimethylbutyl ammonium bromide; The anionic monomer can be one or more mixtures in PAA, Sodium methacrylate, SSS, 2-acrylamido-2-methyl propane sulfonic acid sodium, 2-acrylamido dodecyl sodium sulfate and the ALS.
Among the present invention, said non-ionic water-soluble monomer can adopt one or more mixtures in methacrylic acid, acrylic acid, acrylamide, hydroxyethyl methacrylate, hydroxy propyl methacrylate, methacrylic acid hydroxy butyl ester, hydroxy-ethyl acrylate, acrylic acid hydroxy butyl ester, 2-acrylamido-2-methyl propane sulfonic acid, N-N-isopropylacrylamide, 2-acrylamido dodecyl sodium sulfonate, Dimethylaminoethyl Methacrylate, allyl amine, maleic acid and the itaconic acid.
Among the present invention, said catalyst can be hydrochloric acid, nitric acid, sulfuric acid, acetic acid, phosphoric acid, oxalic acid, ammoniacal liquor, NaOH, sodium carbonate or sodium acid carbonate.
Among the present invention, used surfactant is little molecular surface active agent or high molecular surfactant or their mixture.Wherein, little molecular surface active agent can be that alkyl chain length is that 10 to 18 alkyl sulfate, alkyl chain length are that 10 to 18 alkylbenzenesulfonate, alkyl chain length are 10 to 18 alkyl quaternary ammonium salts, butanedioic acid two (2-ethylhexyl) ester sodium sulfonate, maleic anhydride list 12 ester sodium salts, maleic anhydride list hexadecyl ester sodium salt, maleic anhydride list octadecyl ester sodium salt, tween, sapn or ethylene oxide-propylene oxide copolymer; High molecular surfactant can be random copolymer, graft copolymer or the block copolymer that is formed by hydrophobic monomer and hydrophilic monomer, and said hydrophobic monomer is styrene, methyl styrene, vinylacetate, methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, EMA, butyl methacrylate, glycidyl acrylate, GMA or lauryl methacrylate; Hydrophilic monomer is acrylic acid, methacrylic acid, maleic anhydride, itaconic acid and sodium salt thereof, maleic anhydride monoesters and sodium salt thereof, vinylpyridine, methylacryoyloxyethyl trimethyl ammonium chloride, styrene benzyltrimethylammonium chloride, SSS, 2-acrylamido-2-methyl propane sulfonic acid and sodium salt thereof, 2-acrylamido dodecyl sodium sulfonate, ALS, N, N-DMAA, N, N-diethyl acrylamide, pi-allyl trimethyl ammonium chloride, Dimethylaminoethyl Methacrylate or acrylic acid dimethylamino ethyl ester.
Among the present invention, said hydrophobic monomer can be styrene, methyl styrene, vinylacetate, methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, EMA, butyl methacrylate, glycidyl acrylate, GMA or lauryl methacrylate.
Among the present invention, said silica or titanium dioxide precursor can be one or more mixtures in methyl silicate, ethyl orthosilicate, dimethyldiethoxysilane, metatitanic acid methyl esters, tetraethyl titanate, tetrabutyl titanate, isopropyl titanate, iso-butyl titanate and the titanium tetrachloride solution.
Adopt the inventive method, can change the size of hydrogel microsphere by the degree of cross linking of regulating hydrogel microsphere, thereby obtain the hollow microsphere that particle diameter is 50~1000nm.
Beneficial effect of the present invention is: this method is owing to form the microballoon with hollow structure behind the inner hydrogel microsphere template drying and dehydrating, volume contraction, do not need to remove template by organic solvent dissolution, strong acid and strong base etching or high-temperature calcination, safe preparation process, easy and simple to handle, and can obtain the hollow microsphere that different chemical is formed by change nuclear, husk as raw material.
Description of drawings
Transmission electron microscope (TEM) photo of Fig. 1 polystyrene hollow microsphere;
The TEM photo of Fig. 2 polystyrene hollow microsphere;
The TEM photo of Fig. 3 polystyrene hollow microsphere;
The TEM photo of Fig. 4 polymethyl methacrylate hollow microsphere.
The specific embodiment
Embodiment 1
With 5.0g N-N-isopropylacrylamide (NIPAAm), 0.05gN, N '-methylene-bisacrylamide (BIS) and 50g deionized water place 100ml flask stirring and dissolving, add the 0.005g hexadecyltrimethylammonium chloride, 0.25g methylacryoyloxyethyl trimethyl ammonium chloride (DMC), logical nitrogen is after 60 minutes, add 0.05gN again, N '-azo diisobutyl amidine hydrochloride (AIBA) is warming up to 75 ℃ with oil bath, open condensation reflux unit reaction 8 hours, naturally cool to room temperature and leave standstill and treat its complete swelling half an hour.After the dialysis purifying, drying is got the 0.3g product and is disperseed in the vibration of 50ml deionized water for ultrasonic again, obtains hydrogel microsphere suspension.Hydrogel microsphere suspension is put into the 250ml conical flask as seed, added 150ml ionized water, 0.05g lauryl sodium sulfate (SDS), stirring and logical nitrogen successively 60 minutes, add 0.3g styrene (St), 0.005g divinylbenzene (DVB) again, 0.002g potassium peroxydisulfate (KPS) and 0.001g sodium sulfite (SSA) reaction 48 hours obtain polystyrene hollow microsphere (Fig. 1) after the drying.
Embodiment 2
With 4.0g N-N-isopropylacrylamide (NIPAAm), 0.04gBIS and the 800g deionized water places 1000ml flask stirring and dissolving, add the 0.4g hexadecyltrimethylammonium chloride, 0.2g styrene benzyltrimethylammonium chloride, logical nitrogen is after 60 minutes, add 0.02g AIBA again oil bath is warming up to 60 ℃, open condensation reflux unit reaction 72 hours, naturally cooling to room temperature leaves standstill and treats its complete swelling half an hour, after the dialysis purifying, dry, get the 0.3g product and be scattered in again in the 100ml deionized water, obtain hydrogel microsphere suspension.This hydrogel microsphere suspension is put into the 250ml conical flask as seed, add 150ml ionized water, 0.15g butanedioic acid two (2~ethylhexyl) ester sodium sulfonate, 2.0g St, 0.05gDVB and 0.05gKPS successively, stirring and logical nitrogen 10 minutes, add 0.024g SSA reaction 1 hour again, obtain polystyrene hollow microsphere (Fig. 2) after the drying.
Embodiment 3
With 5.0g N-N-isopropylacrylamide (NIPAAm), 0.01gBIS and the 500g deionized water places 1000ml flask stirring and dissolving, add 1g styrene benzyltrimethylammonium chloride, logical nitrogen is after 60 minutes, add 0.005g AIBA again oil bath is warming up to 60 ℃, open condensation reflux unit reaction 72 hours, naturally cool to room temperature and leave standstill and treat its complete swelling half an hour.After the dialysis purifying, drying is got the 0.3g product and is scattered in the deionized water again, obtains hydrogel microsphere suspension.Get this hydrogel microsphere suspension of 50ml and put into the 250ml conical flask as seed, add 150ml ionized water, 0.057gSDS, 10.0g styrene (St), 0.5g divinylbenzene (DVB) and 0.12gKPS successively, stirring and logical nitrogen 10 minutes, add 0.06g sodium sulfite (SSA) reaction 1 hour again, obtain polystyrene hollow microsphere (Fig. 3) after the drying.
Embodiment 4
With 5.0g N-N-isopropylacrylamide (NIPAAm), 0.5gBIS and the 500g deionized water places 1000ml flask stirring and dissolving, add 0.005g pi-allyl trimethylammonium bromide, logical nitrogen is after 5 minutes, add 0.25gAIBA again oil bath is warming up to 90 ℃, open condensation reflux unit reaction 1 hour, naturally cool to room temperature and leave standstill and treat its complete swelling half an hour.After the dialysis purifying, dry, get the 0.25g product and put into the 250ml conical flask as seed, add 150g ionized water, 0.025gSDS, 1.0g methyl methacrylate, 0.01g methacrylic acid binaryglycol ester and 0.025gKPS successively, stir and logical nitrogen half an hour, add the 0.01g sodium hydrogensulfite again, at room temperature reacted 72 hours, obtain polymethyl methacrylate hollow microsphere (Fig. 4) after the drying.
Embodiment 5
With 6.0g NIPAAm, 0.12gBIS and the 300g deionized water places 500ml flask stirring and dissolving, add the logical nitrogen of 0.2g methylacryoyloxyethyl trimethyl ammonium chloride (DMC) after half an hour, add 0.062gAIBA again oil bath is warming up to 70 ℃, open condensation reflux unit reaction 5 hours, naturally cool to room temperature swelling half an hour.After the suction filtration purifying, dry, get the 5g product and put into the 250ml conical flask as seed, add 60ml deionized water, 0.05g neopelex, 5.0g styrene (St), 0.20gDVB and 0.5g ammonium persulfate successively, stir and logical nitrogen half an hour, add an amount of 0.25gSSA reaction 5 hours again, obtain the polystyrene hollow microsphere after the drying.
Embodiment 6
With 15g NIPAAm, 0.05gBIS, 0.3g AIBA, 0.3g DMC and 300g deionized water place 500ml flask stirring and dissolving, logical nitrogen is warming up to 75 ℃ with oil bath after half an hour, opens condensation reflux unit reaction 24 hours, naturally cools to the room temperature swelling 1 hour.Get the microballoon of 5g drying and put into the 100ml conical flask as seed, add 50g deionized water, 0.05g maleic acid list 18 pure ester sodium salts, 5.00gSt, 0.04gDVB and 0.07gKPS successively, stir and logical nitrogen half an hour, add an amount of 0.03gSSA reaction 5 hours again, obtain the polystyrene hollow microsphere after the drying.
Embodiment 7
With 15g NIPAAm, 0.015gBIS, 0.3gAIBA, 0.3g pi-allyl trimethyl ammonium chloride and 300g deionized water place 500ml flask stirring and dissolving, logical nitrogen is warming up to 75 ℃ with oil bath after half an hour, opens condensation reflux unit reaction 24 hours, naturally cools to the room temperature swelling 1 hour.Get the microballoon of 3.5g drying and put into the 100ml conical flask as seed, add 0.035g maleic acid list lauryl alcohol ester sodium salt successively, 0.047gKPS, the 50g deionized water is put in the 100ml conical flask, add the logical nitrogen of 7gSt monomer and 0.04g crosslinking agent DVB half an hour behind the ultrasonic dissolution, add 0.023gSSA reaction 24 hours, obtain the polystyrene hollow microsphere after the drying.
Embodiment 8
With 15g NIPAAm, 0.015gBIS, 0.3g potassium peroxydisulfate (KPS), 0.3g SSS and 300g deionized water place 500ml flask stirring and dissolving, logical nitrogen is warming up to 75 ℃ with oil bath after half an hour, opens condensation reflux unit reaction 24 hours, naturally cools to the room temperature swelling 1 hour.Get the microballoon of 0.5g drying and put into the 100ml conical flask as seed, add the 0.05g hexadecyltrimethylammonium chloride, logical nitrogen adds 0.50g GMA monomer again after half an hour, 0.0025g hydrogen peroxide and the reaction of 0.0025g frerrous chloride 36 hours obtain the poly (glycidyl methacrylate) hollow microsphere after the drying.
Embodiment 9
With 10gNIPAAm, 0.005gBIS, 0.1g potassium peroxydisulfate (KPS), 0.1g SSS and 300g deionized water place 500ml flask stirring and dissolving, logical nitrogen is warming up to 70 ℃ with oil bath after half an hour, opens condensation reflux unit reaction 24 hours, naturally cools to the room temperature swelling 1 hour.Get the microballoon of 0.75g drying and put into the 100ml conical flask as seed, add the 0.05g DTAC, logical nitrogen adds 0.750g glycidyl acrylate monomer again after half an hour, 0.005g hydrogen peroxide and the reaction of 0.005g ascorbic acid 36 hours obtain the poly (glycidyl methacrylate) hollow microsphere after the drying.
Embodiment 10
With 5.7g N-N-isopropylacrylamide, 0.12gBIS and the 300g deionized water places 500ml flask stirring and dissolving, add the logical nitrogen of 0.06g acrylic acid after half an hour, add 0.24g potassium peroxydisulfate (KPS) again oil bath is warming up to 70 ℃, open condensation reflux unit reaction 5 hours, naturally cool to room temperature and leave standstill and treat its complete swelling half an hour.After dialysis, purifying, the drying, get the 0.3g product and be scattered in again in the 300ml deionized water, obtain hydrogel microsphere suspension.Hydrogel microsphere suspension is put into the 250ml conical flask as seed, add 2.0g ethyl acrylate, 0.05gKPS, 0.4g methyl acrylate-methylacryoyloxyethyl trimethyl ammonium chloride copolymer and 0.02g methacrylic acid binaryglycol ester successively, stir and logical nitrogen half an hour, add 0.03g sodium hydrogensulfite reaction 7 hours again, obtain the polyethyl acrylate hollow microsphere after the drying.
Embodiment 11
With 3.98g acrylamide, 0.02g acrylic acid, 0.04gN, N '-di-2-ethylhexylphosphine oxide (acrylamide) (BIS) and 40g deionized water stirring and dissolving in the 500ml flask, add 80g cyclohexane, 0.1g surfactant OP-10, logical nitrogen after half an hour, add 0.24g potassium peroxydisulfate (KPS) again oil bath is warming up to 70 ℃, open condensation reflux unit reaction 5 hours, after suction filtration, the drying, get the 0.5g product and be scattered in again in the 50ml deionized water, obtain hydrogel microsphere suspension.Hydrogel microsphere suspension is put into the 250ml conical flask as seed, add 150ml ionized water, 2.5g methyl methacrylate, 0.05gKPS, 0.4g methyl methacrylate-allyl ammonium chloride copolymer and 0.02g methacrylic acid binaryglycol ester successively, stir and logical nitrogen half an hour, add 0.04g sodium sulfite reaction 6 hours again, obtain the polymethyl methacrylate hollow microsphere after the drying.
Embodiment 12
With 0.9g hydroxy-ethyl acrylate, 0.1gDMC, 0.001gN, N '-di-2-ethylhexylphosphine oxide (acrylamide) and 1g deionized water stirring and dissolving in the 500ml flask, add 0.01g Tween-60,600ml normal heptane, logical nitrogen added the 0.001g azodiisobutyronitrile again oil bath is warming up to 60 ℃ after 5 minute, reacted 5 hours, after suction filtration, washing, the drying, get the 0.5g product and be scattered in again in the 10ml deionized water, obtain hydrogel microsphere suspension.Hydrogel microsphere suspension is put into the 250ml conical flask as seed, add 100ml ionized water, 0.5g methyl methacrylate, 0.5g styrene, 0.005gDVB, 0.4g methyl methacrylate-metering system sodium copolymer and 0.005gKPS successively, stir and logical nitrogen half an hour, be warming up to 70~90 degree reactions 72 hours, obtain polymethyl methacrylate-styrol copolymer hollow microsphere after the drying.
Embodiment 13
With 1.0g methylacryoyloxyethyl trimethyl ammonium chloride, 0.1gN, N '-di-2-ethylhexylphosphine oxide (acrylamide), 0.5g Tween-60 and 20g deionized water stirring and dissolving in the 500ml flask, add 200g normal heptane, logical nitrogen after 5 minutes, add the 0.1g ABVN again oil bath is warming up to 60 ℃, reacted 5 hours, after suction filtration, washing, the drying, get the 0.5g product and be scattered in again in the 50ml deionized water, obtain hydrogel microsphere suspension.Hydrogel microsphere suspension is put into the 250ml conical flask as seed, add 100g ionized water, 0.01g styrene-SSS copolymer, 0.25g butyl methacrylate, 0.25g methyl styrene, 0.001gDVB and 0.005gKPS successively, stir and helium injection gas half an hour, be warming up to 70~90 degree reactions 36 hours, obtain polybutyl methacrylate-methylstyrene copolymer hollow microsphere after the drying.
Embodiment 14
With 1.0g hydroxyethyl methacrylate, 1.98g acrylic acid hydroxy butyl ester, 0.02g methylacryoyloxyethyl dimethylbutyl ammonium bromide, 0.003gBIS and 30g deionized water stirring and dissolving in the 400ml flask, add 400g normal heptane, the logical nitrogen of 0.2g Arlacel-80 after 5 minutes, add the 0.003g azodiisobutyronitrile again oil bath is warming up to 60 ℃, reacted 5 hours, suction filtration, washing, drying are got the 0.5g product and are scattered in the 50g deionized water again, obtain hydrogel microsphere suspension.Hydrogel microsphere suspension is put into the 250ml conical flask as seed, add 450g ionized water, 0.005g styrene-maleic anhydride copolymer sodium salt, 2.5g styrene, 0.25gDVB and 0.25g4 successively, 4 '-azo two (4-cyanopentanoic acid), stir and logical nitrogen half an hour, be warming up to 90 degree reactions 36 hours, obtain the polystyrene hollow microsphere after the drying.
Embodiment 15
With 15g NIPAAm, 0.3gAIBA, 0.3g DMC and 300g deionized water place 500ml flask stirring and dissolving, logical nitrogen is warming up to 75 ℃ with oil bath after half an hour, open condensation reflux unit reaction 24 hours, naturally cooled to the room temperature swelling 1 hour, after the dialysis purifying, dry, get the 0.2g product and be scattered in again in the 50g deionized water, obtain hydrogel microsphere suspension.Hydrogel microsphere suspension is put into the 250ml conical flask as seed, add 100g ionized water, 0.002gSDS successively, add concentrated hydrochloric acid 0.002g, drip ethyl orthosilicate 1.0g, reacted 24 hours.With the product centrifugation, drying obtains the silica hollow microsphere.
Embodiment 16
With 15gNIPAAm, 0.3gAIBA, 0.3g DMC and 300g deionized water place 500ml flask stirring and dissolving, logical nitrogen is warming up to 70 ℃ with oil bath after half an hour, open condensation reflux unit reaction 36 hours, naturally cooled to the room temperature swelling 1 hour, after the dialysis purifying, dry, get the 0.2g product and be scattered in again in the 50g deionized water, obtain hydrogel microsphere suspension.Hydrogel microsphere suspension is put into the 250ml conical flask as seed, add 150g ionized water, 0.1g styrene-maleic anhydride copolymer sodium salt successively, drip concentrated ammonia liquor 0.01g, drip tetrabutyl titanate 10.0g, reacted 24 hours.With the product centrifugation, drying obtains the titanium dioxide hollow microballoon.
Embodiment 17
With embodiment 16 obtained cationic hydrogel microsphere purifying, drying, get the 0.2g product and be scattered in again in the 200g deionized water, obtain hydrogel microsphere suspension.Hydrogel microsphere suspension is put into the 250ml conical flask add the 5.0g isopropyl titanate, drip concentrated hydrochloric acid 0.005g, after the dialysis.With the product centrifugation, drying obtains the titanium dioxide hollow microballoon.