A kind of preparation method of organosilicon microscapsule powder water-resisting agent
Technical field
The invention belongs to buildings waterproof and solid powdering technical field, relate to a kind of preparation method of organosilicon microscapsule powder water-resisting agent.
Background technology
As everyone knows, organosilicon polymer has two outstanding features: low surface tension and high oxidation resistance voltinism.Low surface tension can produce good hydrophobicity, and the high oxidation resistance voltinism makes silicoorganic compound have oxytolerant, ozone, action of ultraviolet light.Silicoorganic compound have become the main raw that the material of construction hydrophobic is handled, particularly wherein have the silane/polysiloxane-based silicoorganic compound of certain reactive behavior base.When these machine silicon materials are painted on silicate base material surface or mix in its mixture, the siloxanes that has the reactive behavior base, not only can form the reticulated hydrophobic silicone film, can also form the silane chain (as shown in Figure 1) that end has alkyl with the hydroxyl generation condensation reaction in the silicate base material by the interaction of active group.This hydrophobic reticulated siloxane molecule film has very low surface tension, can be evenly distributed on the wall, rather than seal its capillary channel, water the contact angle of capillary wall be 100 °~more than 130 °, make the water that drips thereon become droplet, can't penetrate into base material inside.
Like this, just have the excellent waterproof effect, effectively stop the immersion of moisture, because it does not seal the base material capillary channel, do not hinder steam to spread from inside to outside again, make base material have good ventilation property through the organosilicon treated base material.Because the bond energy of Si-O key is higher, the organosilicon hydrophobic film has excellent weathering resistance, so waterproof effect is lasting again, and the life-span of its waterproof layer generally can reach 10~15 years.
Thereby organosilicon material has been widely used as the water-resisting agent of material of construction such as brick and tile, gravestone, stone inscription, road, bridge, concrete member, pottery as the ideal architectural waterproof material.
Yet waterproofing agent of organosilicon is based on liquid forms such as emulsion or microemulsions, and the liquid repellent agent has shortcomings such as poor stability, difficult transportation storage, and adding water as organoalkoxysilane easily decomposes, and easily causes condensation reaction after decomposing simultaneously, and stable existence is very difficult in water.In addition, the liquid repellent agent can not be used for the dry powder series products, as flourish in recent years dry-mix.
The present invention adopts spray drying method for preparation organosilicon microscapsule powder water-resisting agent.
Spray-drying process is to utilize spraying gun that feed liquid is separated into tiny droplet, and obtains a kind of drying process of powder granular products by warm air (or other gas) and the mode that droplet directly contacts.
General spraying drying comprises four-stage: the feed liquid atomizing; The mist group contacts mixing with the heated drying medium; The evaporation drying of droplet; Drying products separates with drying medium.Fs and subordinate phase are the exclusive features of spraying drying.The purpose of fs atomizing is feed liquid is dispersed into fine fog, and these droplets have large surface area, and when it contact with warm air, moisture is rapid in the droplet vaporized and be dried to powder or particulate product.
Spraying drying begins only to be used for the production of minority products such as powdered egg, milk powder, deepening continuously and develop widespread use in industrial production such as chemistry, medicine, food, cement, pottery, forestry, aquatic products, metallurgy now along with research.
At present, domestic employing spray-drying process has successfully realized micro encapsulation to walnut oil, Chinese gooseberry seed wet goods grease and ginger oil, Chinese prickly ash wet goods essence and flavoring agent.Adopt spray drying method for preparation ginkgo oil microcapsule as people such as Zhang Huanxin, with ginkgo oil be wrapped in cyclodextrin and and the wall material that constitutes of gum arabic in, make its condition influence of avoiding environment, and can shield its taste, color, smell etc.
Summary of the invention
The object of the present invention is to provide a kind of preparation method of organosilicon microscapsule powder water-resisting agent.
For achieving the above object, the technical solution used in the present invention is:
The invention provides a kind of microcapsule of nucleocapsid structure, the organosilicon high-effect water-proof agent is as the nuclear material or claim core to be encapsulated in shell material or the title wall material.The feature request that microcapsule will reach: before microcapsule did not contact water, the organosilicon high-effect water-proof agent was encapsulated in the microcapsule shell material, must not discharge; And once contact water, the organosilicon high-effect water-proof agent discharges immediately, so that further reaction, thereby give the base material hydrophobicity.
Materials such as the needed wall material of organosilicon microscapsule powder of the present invention's preparation, core should be selected according to the feature request that organosilicon microscapsule powder water-resisting agent will reach.
At first select to have the silica-based water-resisting agent of hydrophobic performance.The silicoorganic compound kind that is commonly used for buildings waterproof is more, as silane, polysiloxane, methyl silanol salt, containing hydrogen silicone oil, hydroxy silicon oil and silicone resin etc., silane or polysiloxane particularly to constitute by the alkoxyl group that contains 6~10 carbon atom alkyls and 1~4 carbon atom, have good hydrophobic nature, perviousness, can resist the effect of multiple corrosive medium (diluted acid, alkali, salt, hectic fever air and organic solvent), can stop the erosion of mould.
For can be with silica-based water-resisting agent parcel, and be released after water contact, select water-soluble high molecular polymer as the wall material that wraps up silica-based water-resisting agent.Water-soluble polymers commonly used has polyvinyl alcohol, methyl cellulose ether, hypromellose, Polyvinylpyrolidone (PVP) etc., and wherein using maximum is polyvinyl alcohol.Because it not only has good film-forming properties, bonding force and emulsifying property, and remarkable grease resistance and solvent resistance are arranged.Polyvinyl alcohol makes an addition in the spraying drying dispersion liquid system, can not only wrap up silica-based water-resisting agent as the wall material, and whole system is played the protection stabilization, therefore, often is called as protective colloid.In addition, the powder that is made by polyvinyl alcohol also has good redispersibility.
In order to prevent that polymer beads from taking place to assemble or caking phenomenon, adds a certain amount of filler in system in spray-drying process or later stage storage.The material that is commonly used for filler has superfine inorganic minerals such as silicon-dioxide, lime carbonate, metakaolin.
The present invention is wrapped in formation microcapsule drop in the wall material by the emulsification embedding process with the organosilicon high-effect water-proof agent with wall material, the core of choosing earlier in the aqueous solution, adopt drying process with atomizing that the microcapsule droplet drying is become the organosilicon microscapsule powder again.
A kind of preparation method of organosilicon microscapsule powder water-resisting agent may further comprise the steps:
(1) high molecular weight water soluble polymer wall material is made the aqueous solution;
(2) mineral filler is mixed by a certain percentage with the organosilicon high-effect water-proof agent, form even matter dispersion;
(3) in the dispersion that step (2) obtains, add polymers soln and other auxiliary agents that step (1) obtains, disperse, form even matter and stablize dry dispersion liquid;
(4) the spray-dried waterproofing agent of organosilicon microscapsule powder that obtains certain fineness of the uniform and stable dispersion liquid that step (3) is obtained;
(5) collect product, sealing is preserved.
Described high molecular weight water soluble polymer wall material is selected from one or more in polyvinyl alcohol, methylcellulose gum, carboxymethyl cellulose, Natvosol, hypromellose, Polyvinylpyrolidone (PVP), gelatin, gum arabic natural gum, maltodextrin or the starch etc.; preferably polyethylene alcohol; because it not only has good film-forming properties, bonding force and emulsifying property; but also be outstanding protective colloid, can play stabilization.
In the described step (1), the massfraction of high molecular weight water soluble polymer wall material in solution is 2%~30%, preferred 3%~20%; Solvent temperature is a room temperature to 100 ℃, and dissolution time is smaller or equal to 30min.
Described mineral filler is selected from inorganic mineral filler.
Described inorganic mineral filler is selected from one or more in superfine metakaolin, superfine lime carbonate, superfine white carbon black, superfine silicon-dioxide, superfine zeolite powder or the superfine talcum powder, and its particle diameter is 10~100nm; Its consumption is 0~40% of an efficient waterproofing agent of organosilicon quality, preferred 8%~30%.
Described efficient waterproofing agent of organosilicon is selected from one or both in polysiloxane or the silane.
Described efficient waterproofing agent of organosilicon polysiloxane is polyorganosiloxane fluid or polyorganosiloxane resin, preferred polyorganosiloxane fluid, preferable methyl silicone oil, hydroxy silicon oil, containing hydrogen silicone oil etc.;
The silane that described efficient waterproofing agent of organosilicon silane preferably is made of the alkoxyl group of the alkyl that contains 6~10 carbon atoms and 1~4 carbon atom;
Described efficient organosilicon replica water-resisting agent, be meant that silane and polysiloxane are by 99~50: 1~50 mass ratio is composite, preferred composite mass ratio is 97~70: 3~30, have good hydrophobic nature, perviousness, the effect of multiple corrosive medium (diluted acid, alkali, salt, hectic fever air and organic solvent) can be resisted, the erosion of mould can be stoped.
The consumption of described efficient waterproofing agent of organosilicon accounts for the 25%-80% of organosilicon microscapsule powder total mass.
In the described step (3), high molecular polymer wall material accounts for 10%~60%, preferred 20%~45% of organosilicon microscapsule powder water-resisting agent total mass.
Stirring velocity is 300r/min~3000r/min in the described step (3), and churning time is 0~3h, and stirring velocity is preferably 900r/min~2000r/min; Churning time is preferably 30min~90min.
Described auxiliary agent is an emulsifying agent.
Described emulsifying agent is one or more in anion surfactant, cats product, amphoterics or the nonionogenic tenside, preferred Arlacel-60 (tween-80), Soxylat A 25-7 (Arlacel-80), anhydrous sorbitol list olein (OP-20), one or more of condenses of alkylphenol and oxyethane (OP-10) or Sodium dodecylbenzene sulfonate; Described emulsifying agent consumption is 0~7% of a waterproofing agent of organosilicon consumption.
The drying conditions of described step (4) is: 105 ℃~200 ℃ of inlet temperature, 40 ℃~105 ℃ of temperature outs, fog-spray nozzle rotating speed 10000r/min~35000r/min, input speed can in time be separated into suitable with the liquid material, preferred 125 ℃~180 ℃ of inlet temperature, 60 ℃~90 ℃ of temperature outs, fog-spray nozzle rotating speed 15000r/min~30000r/min.
In the described step (4), the fineness of organosilicon microscapsule powder is 10 μ m~100 μ m, preferred 20~100 μ m.
Polysiloxane in the described organosilicon microscapsule powder water-resisting agent is or/and the content of silane accounts for the 50-80% of organosilicon microscapsule powder water-resisting agent quality.
The invention has the advantages that:
Prepared organic silicon microscapsule powder water-proof material of the present invention is for easily disperseing, can flow the powder of white, mix in cement, concrete, mortar, sealing joints material, gypsum, injection material in can be directly, also can be directly as the additive of dry-mix, inorganic paint and latex powder, with water tolerance and the hydrophobicity of improving them.The present invention adopts solvent-free design, nontoxic pollution-free.The product that the present invention obtains is pulverous organosilicon high-effect water-proof agent, and utmost point low-dosage just can obtain outstanding hydrophobic effect down.
Description of drawings
Fig. 1 the present invention obtains the organosilicon powder water-proof material.
Fig. 2 organosilicon nucleocapsid structure microcapsule synoptic diagram, wherein 1 is organosilicon nuclear; 2 is shell.
The hydrophobic rate curve figure of the organosilicon powder water-proof material that Fig. 3 the present invention obtains.
Embodiment
Be described in further detail below in conjunction with example:
Embodiment 1
(1) solid polyethylene alcohol is added in the room temperature water while stirring, and heat water to about 70 ℃, the about 30min of dissolution time is cooled to room temperature then, concentration 2%;
(2) selecting nano-calcium carbonate is inorganic mineral filler; Polydimethylsiloxane and isobutyl-triethoxyl silane are re-dubbed the efficient waterproofing agent of organosilicon of replica by 3: 97 mass ratio account for 63% of organosilicon microscapsule powder total mass; The nano-calcium carbonate that accounts for efficient waterproofing agent of organosilicon total mass 15% is added in the replica water-resisting agent, put into ultra-sonic dispersion instrument 15min then, make homogeneous dispersion;
(3) polyvinyl alcohol water solution that step (1) is prepared, add in the dispersion of (4) again, make polyvinyl alcohol polymer account for 28% of organosilicon microscapsule powder total mass, place high-shear separating apparatus 30min, stirring velocity 900r/min obtains even matter and stablizes the spraying drying dispersion liquid;
(4) open spray-dryer (OPD-8, great river, Shanghai original equipment company limited), carry out preheating.The dispersion liquid of will spraying then places the feeding unit of spray-dryer to carry out spraying drying, setup parameter: 135 ℃ of inlet temperature, 50 ℃ of temperature outs, fog-spray nozzle rotating speed 15000r/min, input speed 3L/h;
(5) collection rests on spray-dryer and the two-part organosilicon powder of cyclonic separator, and obtaining fineness is the organosilicon microscapsule powder of 50~80 μ m;
Adopt soxhlet extraction to measure the microcapsule productive rate, adopt the granular size and the size distribution of observation by light microscope organosilicon microcapsule product, further use the surface topography and the wall material thickness of scanning electron microscopic observation microcapsule, by friction or section method microcapsule are broken, whether thickness is 0.2~10 μ m, and react in preparation process with each material of infrared spectroscopy spectrum analysis means analysis.
The microcapsule productive rate is 92% in the present embodiment, and organosilicon accounts for 58% of microcapsule total amount, and the microcapsule wall thickness is about 5 μ m.
In vacuum drying process, dispersion liquid will be in vacuum drying oven dry several hrs.In spray exsiccant process, dispersion liquid moment is dried to pressed powder, and the exsiccant time of being heated only is tens of seconds, and spraying drying has than traditional vacuum drying or drying under reduced pressure technology that the dispersion liquid heated time is short, drying efficiency is high; Spray-dired productive rate is up to more than 90%, and vacuum-drying has only about 70%; Product flowability, the shatter value of preparation are good, and particle diameter is thin and even, and redispersible is good; And do not need advantages such as step such as pulverizing.
Embodiment 2
(1) solid polyethylene alcohol is added in the room temperature water while stirring, and heat water to about 70 ℃, the about 30min of dissolution time is cooled to room temperature then, concentration 8%;
(2) selecting the nanometer metakaolin is mineral filler; Polydimethylsiloxane and octyltri-ethoxysilane are re-dubbed the efficient waterproofing agent of organosilicon of replica by 50: 50 mass ratio, and the concrete consumption of waterproofing agent of organosilicon accounts for 66.7% of organosilicon microscapsule powder water-resisting agent total mass in the present embodiment; Take by weighing the nanometer metakaolin that accounts for high-effect water-proof agent total mass 18% again and add in the water-resisting agent, put into ultra-sonic dispersion instrument 30min then, make homogeneous dispersion;
(3) polyvinyl alcohol water solution that step (1) is prepared, add in the dispersed system of (2) again, make polyvinyl alcohol polymer account for 18% of organosilicon microscapsule powder water-resisting agent total mass, and the emulsifying agent of mass ratio preparation in 1: 1.3 is pressed in adding by Arlacel-80 and tween-80, emulsifying agent accounts for 5% of efficient waterproofing agent of organosilicon total mass, place high-shear separating apparatus 1h then, stirring velocity 1500r/min obtains the stable spraying of even matter dispersion liquid;
(4) open spray-dryer (OPD-8, great river, Shanghai original equipment company limited), carry out preheating.Place the feeding unit of spray-dryer to carry out spraying drying, setup parameter the spraying drying dispersion liquid then: 180 ℃ of inlet temperature, 65 ℃ of temperature outs, fog-spray nozzle rotating speed 20000r/min, input speed 3L/h;
(5) collection rests on spray-dryer and the two-part organosilicon powder of separator, and obtaining fineness is the organosilicon microscapsule powder of 10~30 μ m.
The microcapsule productive rate of present embodiment is 90%, and organosilicon accounts for 60% of microcapsule total amount, and the microcapsule wall thickness is about 3 μ m.
The hydrophobic rate curve figure of the organosilicon powder water-proof material that the present invention obtains as described in Figure 2.Wherein sample 1 and sample 2 adopt embodiment 1 and embodiment 2 to obtain organosilicon microscapsule powder product respectively, organosilicon accounts for microcapsule total amount 58% and 60% respectively, liquid organosilicon be polydimethylsiloxane and octyltri-ethoxysilane by 3: 97 composite efficient waterproofing agent of organosilicon of replica of mass ratio, consumption all is to account for 0.3% of dry powder total amount.
Embodiment 3
(1) solid polyethylene alcohol is added in the room temperature water while stirring, and heat water to about 70 ℃, the about 30min of dissolution time is cooled to room temperature then, concentration 20%;
(2) selecting nano silicon is inorganic mineral filler; Selecting the butyl triethoxyl silane is efficient waterproofing agent of organosilicon, and the concrete consumption of waterproofing agent of organosilicon accounts for 54% of organosilicon microscapsule powder water-resisting agent total mass in the present embodiment; The nano silicon that accounts for efficient waterproofing agent of organosilicon total mass 8% is added in the water-resisting agent, put into ultra-sonic dispersion instrument 15min then, make homogeneous dispersion;
(3) polyvinyl alcohol water solution that step (1) is prepared, add in the dispersion of (2) again, make polyvinyl alcohol polymer account for 42% of organosilicon microscapsule powder water-resisting agent total mass, place high-shear separating apparatus 90min, stirring velocity 2000r/min obtains even matter and stablizes the spraying drying dispersion liquid;
(4) open spray-dryer (OPD-8, great river, Shanghai original equipment company limited), carry out preheating; The dispersion liquid of will spraying then places the feeding unit of spray-dryer to carry out spraying drying, setup parameter: 160 ℃ of inlet temperature, 75 ℃ of temperature outs, fog-spray nozzle rotating speed 30000r/min, input speed 3L/h;
(5) collection rests on spray-dryer and the two-part organosilicon powder of cyclonic separator, and obtaining fineness is the organosilicon microscapsule powder of 10~20 μ m.
The microcapsule productive rate is 95% in the present embodiment, and organosilicon accounts for 51.3% of microcapsule total amount, and the microcapsule wall thickness is 8 μ m.
Embodiment 4
(1) the filmogen Natvosol is dissolved in the room temperature water, and adds while stirring in the entry, dissolution time is greater than 20min, and massfraction is 30%.
(2) talcum powder of selecting to be approximately 100nm is an inorganic mineral filler; Selecting Union carbide A-162 is efficient waterproofing agent of organosilicon, and the concrete consumption of waterproofing agent of organosilicon accounts for 55% of organosilicon microscapsule powder water-resisting agent total amount in the present embodiment; The nano silicon that accounts for efficient waterproofing agent of organosilicon total mass 20% is added in the water-resisting agent, put into ultra-sonic dispersion instrument 15min then, make homogeneous dispersion;
(3) hydroxyethyl cellulose aqueous solution that step (1) is prepared, add in the dispersion of (2) again, make the hydroxy ethyl fiber polymkeric substance account for 30% of organosilicon microscapsule powder water-resisting agent total mass, and adding accounts for the emulsifier tween-60 of organosilicon high-effect water-proof agent quality 7%, place high-shear separating apparatus 90min, stirring velocity 2000r/min obtains even matter and stablizes the spraying drying dispersion liquid;
(4) open spray-dryer (OPD-8, great river, Shanghai original equipment company limited), carry out preheating; The dispersion liquid of will spraying then places the feeding unit of spray-dryer to carry out spraying drying, setup parameter: 200 ℃ of inlet temperature, 80 ℃ of temperature outs, fog-spray nozzle rotating speed 30000r/min, input speed 3L/h;
(5) collection rests on spray-dryer and the two-part organosilicon powder of cyclonic separator, and obtaining fineness is the organosilicon microscapsule powder of 10~30 μ m.
The microcapsule productive rate is 90% in the present embodiment, and organosilicon accounts for 50% of microcapsule total amount, and the microcapsule wall thickness is 8 μ m.
The present invention obtains organosilicon powder water-resisting agent (as shown in Figure 2), is white powder, and wherein 1 is organosilicon nuclear; 2 is shell.Silica-based high-efficiency water-resisting agent content is about 60%, and recommending volume is 0.15%~0.5% of gelling material.By mortar water regain testing method among the standard JC474-2008, contrast add the organosilicon powder water-resisting agent mortar, add not treated liquid organosilicon water-resisting agent and do not add the water-intake rate of the blank mortar of any water-resisting agent, result such as Fig. 3, wherein sample 1 and sample 2 are that embodiment 1 and embodiment 2 obtain organosilicon powder.The mortar specimen water-intake rate that has as can be seen from the figure added water-resisting agent of the present invention is much smaller than blank mortar, even the continuous absorbent time of mortar reaches 21d, the mortar water regain is also very little, illustrates that waterproofing agent of organosilicon has long-term water tolerance.In addition, with liquid organosilicon make Powdered after, its hydrophobic performance does not descend, and illustrates that spray-drying process does not change the performance of former liquid waterproofing agent of organosilicon.
The above-mentioned description to embodiment is can understand and apply the invention for ease of those skilled in the art.The person skilled in the art obviously can easily make various modifications to these embodiment, and needn't pass through performing creative labour being applied in the General Principle of this explanation among other embodiment.Therefore, the invention is not restricted to the embodiment here, those skilled in the art are according to announcement of the present invention, and not breaking away from the improvement that category of the present invention makes and revise all should be within protection scope of the present invention.