Patent Application
20150098883
This invention belongs to the technical field of nanomaterials, which relates to use of lactam as a solvent in preparation of nanomaterials.
Nanomaterials refer to those with at least one dimension in three-dimensional space within the nanoscale range (1-100 nm) or materials constituted by them as basic units. Nano-size effects often exhibit melting points and magnetic, optical, thermal conduction and electrical conduction characteristics which are different from bulk materials, so they can be widely used in optoelectronic materials, ceramic materials, sensors, semiconductor materials, catalytic materials, medical treatment and other fields.
Currently, the methods for synthesis of nanomaterials mainly include three categories: solid phase method, liquid phase method and gas phase method. Since nanomaterials have high surface energy, it is hard for nanomaterials obtained by various solid-phase synthesis methods, including high-temperature calcination and mechanical milling, to reach the characteristics of ultrafine size, narrow size distribution and high dispersibility. Gas phase method is an important method for synthesis of ultrafine nanopowder, for example, vapor deposition method is the technology most widely used in semiconductor industry to deposit a variety of nanomaterials, but this process has higher equipment requirements, and deposition of nanoparticles in matrix is often accompanied with permanent agglomeration of the nanoparticles, so it is difficult to ensure their monodispersity. Compared to the former two methods, liquid phase method can prepare nanomaterials of various morphologies and sizes by selecting appropriate solvents and additives. Currently, due to low cost and wide sources, water is the most commonly used solvent in liquid phase method. However, water has high polarity, the raw materials for synthesis of nanomaterials react fast in this medium, and it is very difficult to simply use water as the solvent for controlled synthesis of ideal nanomaterials, so improvement is generally made by adding surfactants and changing synthesis process. In almost all the methods currently reported in literatures and patents for synthesis of nanomaterials of monodispersity, small size and narrow distribution with water solvent system, surfactants or surfactant-like additives are used. These surfactants or additives not only increase the cost for preparation of nanomaterials, but also inevitably remain on the surface of nanomaterials, thus affecting their subsequent use, for example, residues may intoxicate some catalytic nanomaterials, affect biocompatibility of medical nanomaterials, etc.
Recently, a literature has reported use of organics as the solvents for synthesis of nanomaterials, such as the “alcohol-thermal method” using ethanol, ethylene glycol, propylene glycol, polyethylene glycol, etc. as the solvents and high-temperature pyrolysis, with oleic acid as the solvent, of metal oleate, carbonyl salts or acetylacetone to prepare oxides, but these methods still require to use surfactants or expensive organic metal salts, and even some synthetic routes need to consume organic solvents to provide oxygen required to produce oxides, which is not conducive to application of these methods [see specific literature: Magnetite Nanocrystals: Nonaqueous Synthesis, Characterization, and Solubility, Chem. Mater 2005, 17, 3044-3049].
Lactam is an organic compound containing amide groups in cycles, for its derivatives, some nitrogen atoms and hydrogen on carbon can be substituted by other groups, among which, butyrolactam (also called α-pyrrolidone) containing four carbon atoms is liquid at room temperature and a commonly used high-boiling-point polar solvent in organic synthesis. Recently. Gao, et al. has synthesized super paramagnetic ferroferric oxide <20 nm in size with carbonyl iron and ferric trichloride in butyrolactam solvent [see specific literature: One-Pot Reaction to Synthesize Water-Soluble Magnetite Nanocrystals, Chem. Mater., Vol. 16, No. 8, 2004; Preparation of Water-Soluble Magnetite Nanocrystals from Hydrated Ferric Salts in 2-Pyrrolidone: Mechanism Leading to Fe3O4, Angew. Chem. Int. Ed. 2005, 44, 123-126]. Butyrolactam used in this method itself is a highly toxic solvent, which brings great threat to production safety and environmental protection; More importantly, butyrolactam has a strong coordination effect and can be firmly adsorbed on the surface of nanomaterials, which will certainly affect the subsequent use of nanomaterials containing toxic components, especially in medical treatment, health, food and other fields. In addition, other literatures were restricted to synthesis of nano ferroferric oxide with butyrolactam as the solvent, but not investigated other oxides, hydroxides and metal nanomaterials.
Among lactams, except butyrolactam, cyclic lactams containing 5 or more carbon atoms in cycles are solid as room temperature, and the melting point increases with the number of carbon atoms, for example, the melting point was 39 C. for valerolactam. 68° C. for caprolactam and up to 153° C. for laurolactam, so it is difficult to think about through butyrolactam that lactams containing 5 or more carbon atoms should be used as the solvents for organic synthesis, and moreover, there is no report on use of them alone as the solvents for synthesis of nanomaterials. Such substances have the structures similar to that of butyrolactam, and at temperature higher than their melting points, they have relatively strong polarity, but weaker than the polarity of water, so they can not only guarantee certain solubility of raw materials for synthesis of nanomaterials in the solvents, but also slow down the reactions, thus they are a kind of ideal solvents for synthesis of nanomaterials. Most importantly, lactam's amide groups have a coordination effect and can play a role similar to surfactant, so no other surfactants are required for synthesis of nanomaterials when using this solvent. Furthermore, lactam derivatives contains two amide groups in the cycles, for example, succinimide, glutarimide, adipimide also have similar characteristics. Therefore, lactams containing 5 or more carbon atoms, above their melting points, can substitute other common solvents for preparation of nanomaterials.
For shortages of solid phase method, gas phase method and liquid phase method in existing techniques that are not conducive to preparation of nanomaterials with ultrafine size, narrow size distribution and high dispersibility, especially for the high toxicity of butyrolactam, which affects subsequent use of the synthetic nanoparticles, the present invention is to provide use of lactams as the solvents for preparation of nanomaterials.
The technical solutions of this invention are as follows:
This invention provides use of lactams as solvent in the synthesis of nanomaterials.
The lactam is one or more of substances selected from cyclic amides or cyclic amide derivatives.
The general structural formula of the mentioned cyclic amides is:
From vaterolactam, caprolactam, cenantholactam, 2-azacyclononanone, nonanoylamide, caprinlactam, undcanoylamide, laurolactam, glurarimide or adipimide, in which caprolactam, laurolactam, glutarimide or adipimide are preferred, and caprolactam is more preferred.
The general structural formula of the mentioned cyclic amide derivatives is:
R0, R1, R2, R3 - - - Rn is one or more of substances selected from hydrogen, halogen, alkyl, hydroxy, alkoxy or acyl, wherein: halogen is selected from fluorine, chlorine, bromine or iodine; alkyl is selected from methyl, ethyl or propyl; alkoxy is selected from methoxy, ethoxy or propoxy; acyl is selected from acetyl or propionyl.
The cyclic amide derivatives are selected from N-methylvalerolactam, N-methylcaprolactam, N-vinylcaprolactam or N-methoxycaprolactam, and N-methylcaprolactam is preferred.
The nanomaterials refer to substances containing inorganic particles with 1 nm<particle size≦100 nm; the content of the inorganic particles is no less than 0.01%; the inorganic particles are mixtures composed of one or more of substances selected from hydroxides, oxides, sulfides, metals or inorganic salts.
The hydroxides refer to water-insoluble or slightly water-soluble inorganic compounds formed by one or more than one metal elements and hydroxyl, preferably mixtures composed of one or more of substances further selected from Ni(OH)2, Mg(OH)2, Al(OH)3, Nd(OH)3, Y(OH)3, Mg—Al hydrotalcite or Zn—Al hydrotalcite;
The oxides refer to water insoluble or slightly soluble inorganic compounds formed by one or more metal elements or metalloid elements and oxygen, preferably mixtures composed of one or more of substances further selected from Ag2O, ZnO, Cu2O, Fe3O4, SiO2, MgAl2O4 or CaTiO3, preferably from Ag2O, ZnO, Cu2O or Fe3O4;
The sulfides are the water insoluble or slightly soluble inorganic compounds formed by binding metal elements or metalloid elements with sulfur, selenium, tellurium, arsenic or antimony, preferably mixtures composed of one or more of substances further selected from CuS, ZnS, CdS, CdSe, CdTe, WSe2, CuTe, CoAs2 or GaAs, preferably ZnS, CdS, CdSe or CdTe;
The metals are water insoluble or slightly soluble substances composed of one or more of metal elements selected from Group IIIA, IVA, IB, IIB or VIII in the periodic table of elements, preferably are alloys or mixtures composed of one or more of substances selected from Fe, Ni, Cu, Ag, Pd, Pt, Au or Ru, preferably from Cu, Ag, Au, Pd or Cu—Ag alloy;
The inorganic salts refer to water insoluble or slightly soluble inorganic compounds formed by binding positive ions of metal elements with carbonate, sulfate, silicate or halogen negative ions, preferably mixtures composed of one or more of substances selected from CaCO3, MgCO3, BaSO4, CaSiO3, AgCl, AgBr or CaF2, preferably from MgCO3, BaSO4, AgCl or CaF2.
This invention also provides a method of using lactams as the solvents for preparation of nanomaterials. Lactams can partly or completely substitute currently commonly used solvents, including water, alcohol, polyhydric alcohols with molecular weight no higher than 5000, oleic acid and α-pyrrolidone, for preparation of various nanomaterials.
The methods for the lactam as a solvent for synthesis of nanomaterials include precipitation method, sol-gel method or high temperature pyrolysis.
The precipitation method for synthesis of nanomaterials includes the following steps: add 0.01-100 weight parts of precursor and 100 weight parts of lactam into the reactor and stir at 80-200° C. for 0.1-2 h to make the precursor fully dissolved or dispersed in the molten lactam solvent, when stirring, add 0.05-50 weight parts of precipitant for sufficient precipitation reaction, with the reaction temperature of 80-250° C. and the reaction time of 0.1-200 h, and obtain the nanomaterials after washing with water, separation and drying.
The lactam solvent has a purity ≧60% and moisture ≦30%;
The precursor is selected from soluble inorganic salts formed by binding metal cations with halogen, nitrate, nitrite, sulfate, sulfite or carbonate anions, further from MgCl2.6H2O, Nd(NO3)3.6H2O, Y(NO3)3.6H2O, AlCl3.9H2O, Al2(SO4)3.18H2O, ZnCl2, AgNO3, CuSO4.5H2O, FeCl2.4H2O, FeCl3.6H2O, Cd(NO3)2.2H2O, BaCl2 or PdCl2; or from organic compounds containing metals or metalloids, further from zinc acetate, carbonyl iron, iron acetylacetonate, iron oleate, butyl titanate or tetraethyl orthosilicate;
The precipitant is selected from alkali metals, alkali metal oxides, alkali metal hydroxides, alkali metal organic salts, ammonia and compounds able to release ammonia by pyrolysis, soluble inorganic salts formed by metal elements and halogen elements, soluble inorganic salts formed by metal elements and chalcogens, soluble inorganic salts formed by metal elements and carbonate, or soluble inorganic salts formed by metal elements and sulfate; in which, alkali metals are further selected from Li, Na or K; alkali metal oxides are further selected from Na2O, K2O, Na2O2 or K2O2; alkali metal hydroxides are further selected from NaOH or KOH; alkali metal organic salts are further selected from sodium methoxide, sodium ethoxide, sodium phenoxide, potassium oleate, sodium lactam or potassium caprolactam; ammonia and compounds able to release ammonia by pyrolysis are further selected from ammonia gas, ammonia water, urea, ammonium carbonate or ammonium bicarbonate, preferably ammonia water, soluble inorganic salts formed by metal elements and halogen elements are further selected from NaCl, KCl, MgCl2, CaCl2, AlCl3.6H2O, FeCl2.4H2O or FeCl3.6H2O, preferably NaCl or KCl; soluble inorganic salts formed by metal elements and chalcogens are further selected from Na2S, K2S, Na2S.9H2O, Na2Se or NaHTe; soluble inorganic salts formed by metal elements and carbonate are further selected from Na2CO3 or K2CO3; soluble inorganic salts formed by metal elements and sulfate are further selected from Na2SO4 or K2SO4.
During synthesis of nanomaterials by the precipitation method, after adding precipitant, further add 0.05-50 weight pans of reductant.
The sol-gel method for synthesis of nanomaterials with lactam as the solvent includes the following steps: add 0.01-100 weight parts of hydrolyzable precursor and 100 weight parts of lactam into the reactor and stir at 80-150° C. for 0.1-2 h to make the precursor fully dissolved or dispersed in the molten lactam solvent, and add 0.01-50 weight parts of water for hydrolysis to obtain sol, with the hydrolysis temperature of 80˜250° C. and hydrolysis time of 0.01˜48 h; perform gelatinization at 80˜270° C. for 0.01˜96 h. and obtain the nanomaterials after washing with water, separation and drying.
The hydrolyzable precursor is selected from hydrolyzable inorganic salts formed by binding metal cations with halogen, nitrate, sulfate or acetate anions or from metal organics; wherein: hydrolyzable inorganic salts formed by binding metal cations with halogen, nitrate, sulfate or acetate anions are further selected from FeCl2.4H2O, FeCl3, FeCl3.6H2O, Fe(NO3)3.6H2O, Fe2(SO4)3, AlCl3, AlCl3.6H2O, CuSO4.5H2O, CuCl2, CuCl2.2H2O, TiCl4 TiCl4 or Zn(OAc)2.2H2O preferably FeCl3.6H2O or AlCl3; metal organics are further selected from diethyl aluminium chloride, aluminum isopropoxide, diethyl zinc, tetraethyl orthosilicate, butyl titanate or tetraethyl titanate, preferably tetraethyl orthosilicate or butyl titanate;
The lactam solvent has a purity ≧60% and moisture ≦30%.
During synthesis of nanomaterials by the sol-gel method, after hydrolysis, further add 0.05-50 weight pans of reductant.
The high temperature pyrolysis method for synthesis of nanomaterials with lactam as the solvent includes the following steps: add 0.01-100 weight parts of pyrolyzable precursor and 100 weight parts of lactam into the reactor and stir at 80-150° C. for 0.1.2 h to make the precursor fully dissolved or dispersed in the molten lactam solvent, perform pyrolysis at 100-270° C. for 0.1˜20 h, and obtain the nanomaterials after washing with water, separation and drying.
The pyrolyzable precursor is selected from soluble inorganic salts pyrolyzable in solvent no higher than 280° C. or from metal organics pyrolyzable in solvent no higher than 280° C.; in which, soluble inorganic salts pyrolyzable in solvent no higher than 280° C. are further selected from AgNO3, FeCl3, Zn(OAc)2 or TiCl4; metal organics pyrolyzable in solvent no higher than 280° C. are further selected from oleate, levulinate or carbonyl salts, preferably ferric oleate, acetylacetone or carbonyl iron (Fe(CO)5).
During synthesis of nanomaterials by the high temperature pyrolysis, after adding lactam, further add 0.05-50 weight parts of anion donors.
The anion donors are selected from compounds pyrolyzable at the temperature of ≦280° C. and able to produce anions required for synthesis of nanomaterials, further selected from benzyl alcohol, trioctylphosphine oxide (provide O2− required for synthesis of oxides) or tetramethyl thiuram disulfide (provide S2− required for synthesis of sulfides).
During synthesis of mixtures including nanoparticles/lactam by the high temperature pyrolysis, before pyrolysis at 100-270° C., further add 0.05-50 weight parts of reluctant.
The reductant is selected from ascorbic acid, potassium borohydride, sodium borohydride, hydrazine, hydrazine hydrate, hydroxylamine or aldehyde group-containing organics; in which: aldehyde group-containing organics are further selected from formaldehyde, acetaldehyde, glyoxal, benzaldehyde or glucose.
During synthesis of nanomaterials by the precipitation method, sol-gel method or high temperature pyrolysis, after adding lactam, further add 0.01-20 weight parts of stabilizer or 0.1-80 weight parts of insoluble inorganics.
The stabilizer is selected from anionic surfactant, cationic surfactant, amphoteric surfactant or nonionic surfactant that adjusts the morphology of synthetic nanomaterials, in which: anionic surfactant is further selected from sodium dodecyl sulfate, sodium alkyl benzene sulfonate or sodium oleate, cationic surfactant is further selected from tetrapropylammonium hydroxide, tetrapropylammonium bromide, tetrapropylammonium chloride, cetyltrimethylammonium bromide, cetyltrimethylammonium chloride or dodecyltriethylammonium bromide, amphoteric surfactant is further selected from dodecyl ethoxy sulfobetaine, octadecyl 2 hydroxyethyl amine oxide or octadecanamide dimethylamine oxide, and nonionic surfactant is further selected from triblock copolymer(P123, PEO-PPO-PEO), polyethylene glycol, polyvinyl pyridine, glycerol or 2-mercaptopropionic acid.
The insoluble inorganics are selected from the substances as the carrier or attachment point for synthesis of nanomaterials, further from activated carbon, graphene, carbon fibers, carbon nanotubes, molecular sieves, smectite clay, diatomaceous earth, glass fibers or glass microspheres.
The methods applicable to synthesis of nanomaterials with lactams as solvents also include cooperative use of precipitation method, sol-gel method, or high-temperature pyrolysis.
As the fact that presently lactams are only used as medical and pharmaceutical raw materials, polymer monomers and chemical intermediates, this invention has developed a new use of lactams as solvents for synthesis of nanomaterials.
Compared to existing techniques, this invention has the following advantages and beneficial effects:
1. Compared to other traditional uses, lactams, as the solvents for preparation of nanomaterials, have the following advantages: 1) nanomaterials belong to an emerging technology field and have added value higher than that of traditional polymers and pharmaceutical intermediates; 2) as solvents, if recovery conditions are appropriate, they can be recycled, which complies with environmental protection requirements.
2. In the field of synthesis of nanomaterials with liquid phase method, compared to water or other organic solvents, lactam solvents have the following advantages: 1) nanoparticles with the size of no larger than 100 nm can be synthesized with or without adding surfactant; 2) lactam solvents can well dissolve common water-soluble salts and organic metals, and under the premise of ensuring small size, high dispersibility and high crystallinity, the yield of nanoparticles per unit mass is high; 3) the synthesized oxide nanoparticles have narrow size distribution and high dispersibility and no residual surfactant; 4) lactam solvents have high boiling point and have no pressure-resistant requirements to reaction equipments at high-temperature synthesis; 5) lactam solvents do not participate in chemical reactions throughout the preparation and can be recycled, and are suitable for large scale industrial production; 6) compared to butyrolactam with hightoxicity, lactam solvents used in this invention have low toxicity.
3. The raw materials used for this method are at low cost, production equipments are simple, and synthetic routes are environmentally friendly, and this method is suitable for large-scale industrial production.
Further explanations are made to this invention in combination with the embodiments shown in the following diagrams.
Add 20.3 g MgCl2.6H2O into 100 g melten caprolactam (purity of caprolactam ≧80%, moisture ≦20%) and stir at 100° C. for 30 min to make MgCl2 fully dissolved. When stirring, rapidly add 10 g ammonia water (containing ammonia: 26%) and keep at constant temperature of 100° C. for 24 h. Wash the obtained mixture with 200 g deionized water by centrifugation for three times, and obtain nano-Mg(OH)2 powder after intensive drying and crushing.
Add 10.96 g Nd(NO3)3.6H2O into 100 g melten caprolactam (purity of caprolactam ≧80%, moisture ≦20%) and stir at 200° C. for 30 min to make Nd(NO3)3.6H2O fully dissolved. When stirring, rapidly add 3 g NaOH and keep at constant temperature of 200° C. for 24 h. Wash the obtained mixture with 200 g deionized water by centrifugation for three times, and obtain nano-Nd(OH)3 powder after intensive drying and crushing.
Add 3.83 g Y(NO3)3.6H2O and 4.02 g AlCl3.9H2O (molar ratio: [Y3+]/[Al3+]=3/5) into 100 g melten caprolactam (purity of caprolactam ≧80%, moisture ≦20%) and stir at 200° C. for 30 min to make Y(NO3)3.6H2O and AlCl3.9H2O fully dissolved. When stirring, rapidly add 8 g NaOH and keep at constant temperature of 200° C. for 24 h. Wash the obtained mixture with 200 g deionized water by centrifugation for three times, and obtain nano-Al(OH)3/Y(OH)3 powder after intensive drying and crushing.
Add 2.03 g MgCl2.6H2O and 3.33 g Al2(SO4)3.18H2O into 100 g melten valerolactam (purity of valerolactam >80%, moisture ≦20%) and stir at 120° C. for 30 min to make the raw materials fully dissolved, and add 1.4 g NaOH and 1.86 g Na2CO3 and keep at constant temperature of 150° C. for 24 h. Wash the obtained mixture with 200 g deionized water by centrifugation for three times, and obtain nano-Mg-Al hydrotalcite powder after intensive drying and crushing.
Add 4.24 g AgNO3 into 100 g melten caprolactam (purity of caprolactam ≧60%, moisture ≦30%) and stir at 80° C. for 30 min to make AgNO3 fully dissolved. When stirring, rapidly add 1 g NaOH and keep at constant temperature of 100° C. for 2 h. Wash the obtained mixture with 200 g deionized water by centrifugation for three times, and obtain nano-Ag2O powder after intensive drying and crushing.
Add 3.41 g ZnCl2 into 100 g melten caprolactam (purity of caprolactam ≧80%, moisture ≦20%) and stir at 150° C. for 30 min to make ZnCl2 fully dissolved. When stirring, rapidly add 2 g NaOH and keep at constant temperature of 100° C. for 2 h. Wash the obtained mixture with 200 g deionized water by centrifugation for three times, and obtain nano-ZnO powder after intensive drying and crushing.
Add 3.41 g ZnCl2 into 100 g melten valerolactam (purity of valerolactam ≧80%, moisture ≦20%) and stir at 150° C. for 30 min to make ZnCl2 fully dissolved. When stirring, rapidly add 2 g NaOH and keep at constant temperature of 100° C. for 2 h. Wash the obtained mixture with 200 g deionized water by centrifugation for three times, and obtain nano-ZnO powder after intensive drying and crushing.
Add 3.41 g ZnCl2 into 100 g melten laurolactam (purity of laurolactam ≧90%, moisture ≦55%) and stir at 160° C. for 30 min to make ZnCl2 fully dissolved. When stirring, rapidly add 2 g NaOH and keep at constant temperature of 100° C. for 2 h. Wash the obtained mixture with 200 g deionized water by centrifugation for three times, and obtain nano-ZnO powder after intensive drying and crushing.
Add 3.41 g ZnCl2 into mixed lactam solvent composed of 80 g caprolactam and 20 g laurolactam (purity of caprolactam and laurolactam ≧90%, moisture ≦5%) and stir at 160° C. for 30 min to make ZnCl2 fully dissolved. When stirring, rapidly add 2 g NaOH and keep at constant temperature of 100° C. for 2 h. Wash the obtained mixture with 200 g deionized water by centrifugation for three times, and obtain nano-ZnO powder after intensive drying and crushing, with the size of about 12 nm.
Add 3.41 g ZnCl2 into mixed lactam solvent composed of 80 g caprolactam and 20 g N-methylcaprolactam (purity of caprolactam and N-methylcaprolactam ≧90%, moisture ≦5%) and stir at 160° C. for 30 min to make ZnCl2 fully dissolved. When stirring, rapidly add 2 g NaOH and keep at constant temperature of 100° C. for 2 h. Wash the obtained mixture with 200 g deionized water by centrifugation for three times, and obtain nano-ZnO powder after intensive drying and crushing, with the size of about 10 nm.
Add 3.41 g ZnCl2 into mixed lactam solvent composed of 20 g valerolactam, 60 g caprolactam and 20 g laurolactam (purity of caprolactam ≧90%, moisture ≦5%; purity of valerolactam and laurolactam ≧80%, moisture ≦20%) and stir at 160° C. for 30 min to make ZnCl2 fully dissolved. When stirring, rapidly add 2 g NaOH and keep at constant temperature of 100° C. for 2 h. Wash the obtained mixture with 200 g deionized water by centrifugation for three times, and obtain nano-ZnO powder after intensive drying and crushing, with the size of about 10 nm, indicating that the size of synthetic nanomaterials can be effectively adjusted by changing the components of lactam solvent.
Add 3.41 g ZnCl2 into 100 g melten adipamide (purity of adipamide ≧90%, moisture ≦5%) and stir at 160° C. for 30 min to make ZnCl2 fully dissolved. When stirring, rapidly add 2 g NaOH and keep at constant temperature of 100° C. for 2 h. Wash the obtained mixture with 200 g deionized water by centrifugation for three times, and obtain nano-ZnO powder after intensive drying and crushing.
Add 3.41 g ZnCl2 into 100 g melten N-methylcaprolactam (purity of N-methylcaprolactam ≧99%, moisture <0.2%) and stir at 160° C. for 30 min to make ZnCl2 fully dissolved. When stirring, rapidly add 2 g NaOH and keep at constant temperature of 100° C. for 8 h. Wash the obtained mixture with 200 g deionized water by centrifugation for three times, and obtain nano-ZnO powder after intensive drying and crushing.
Add 6.242 g CuSO4.5H2O into 100 g melten caprolactam (purity of caprolactam ≧80%, moisture ≦20%) and stir at 100° C. for 30 min to make CuSO4.5H2O fully dissolved. When stirring, rapidly add 2 g NaOH and keep at constant temperature of 100° C. for 2 h. Wash the obtained mixture with 200 g deionized water by centrifugation for three times, and obtain nano-CuO powder after intensive drying and crushing.
Add 4.1 g FeCl2.4H2O and 8.2 g FeCl3.6H2O into 100 g melten caprolactam (purity of caprolactam ≧80%, moisture ≦20%) and stir at 150° C. for 30 min to make them fully dissolved. When stirring, rapidly add 9.8 g KOH and keep at constant temperature of 100° C. for 2 h. Wash the obtained mixture with 200 g deionized water by centrifugation for three times, and obtain nano-Fe3O powder after intensive drying and crushing.
Add 20.3 g MgCl2.6H2O into 100 g melten caprolactam (purity of caprolactam ≧80%, moisture ≦20%) and stir at 100° C. for 30 min to make MgCl2 fully dissolved. When stirring, rapidly add 15 g Na2CO3 and keep at constant temperature of 100° C. for 24 h. Wash the obtained mixture with 200 g deionized water by centrifugation for three times, and obtain nano-MgCO3 powder after intensive drying and crushing. The product is in flake structure, with the thickness of about 5 nm and long diameter of 60 nm.
Add 5.6 g BaCl2 into 100 g melten caprolactam (purity of caprolactam ≧80%, moisture ≦20%) and stir at 100° C. for 30 min to make MgCl2 fully dissolved. When stirring, rapidly add 3.0 g Na2SO4 and keep at constant temperature of 100° C. for 24 h. Wash the obtained mixture with 200 g deionized water by centrifugation for three times, and obtain nano-BaSO4 powder after intensive drying and crushing. The product is in flake structure, with the thickness of about 4 nm and long diameter of 90 nm.
Add 2.1 g AgNO3 into 100 g melten caprolactam (purity of caprolactam ≧80%, moisture ≧20%) and stir at 100° C. for 30 min to make AgNO3 fully dissolved. When stirring, rapidly add 1.5 g NaCl and keep at constant temperature of 100° C. for 24 h. Wash the obtained mixture with 200 g deionized water by centrifugation for three times, and obtain nano-AgCl powder after intensive drying and crushing. The product is composed of spherical particles, with the size of about 3 nm.
Add 10.0 g ZnCl2 into 100 g melten caprolactam (purity of caprolactam ≧80%, moisture ≦20%) and stir at 100° C. for 30 min to make ZnCl2 fully dissolved. When stirring, rapidly add 12.0 g Na2S.9H2O and keep at constant temperature of 150° C. for 12 h. Wash the obtained mixture with 200 g deionized water by centrifugation for three times, and obtain nano-ZnS powder after intensive drying and crushing.
Add 7.71 g Cd(NO3).2H2O into 100 g melten caprolactam (purity of caprolactam ≧80%, moisture ≦20%) and stir at 100° C. for 30 min to make Cd(NO3)2.2H2O fully dissolved. When stirring, rapidly add 3 g Na2Se and keep at constant temperature of 150° C. for 12 h. Wash the obtained mixture with 200 g deionized water by centrifugation for three times, and obtain nano-CdSe powder after intensive drying and crushing.
Add 0.82 g Cd(NO3)2.2H2O and 0.54 ml 2-mercaptopropionic acid (stabilizer) into 100 g melten caprolactam (purity of caprolactam ≧90%, moisture ≦1%) and stir at 80° C. for 30 min to make Cd(NO3)2.2H2O and 2-mercaptopropionic acid fully dissolved. Under the protection of nitrogen, rapidly add 0.5 g NaHTe and keep at constant temperature of 90° C. for 4 h. Wash the obtained mixture with 200 g deionized water by centrifugation for three times, and obtain nano-CdTe powder after intensive drying and crushing.
Add 4.24 g AgNO3 into 100 g melten caprolactam (purity of caprolactam ≧80%, moisture ≦20%) and stir at 100° C. for 30 min to make AgNO3 fully dissolved. When stirring, rapidly add 1 g NaOH and keep at constant temperature of 100° C. for 2 h. and then add 2 g NaBH for continued reaction for 1 h. Wash the obtained mixture with 200 g deionized water by centrifugation for three times, and obtain nano-Ag powder after intensive drying and crushing.
Add 4.24 g AgNO3 and 10 g cetyltrimethylammonium bromide into 100 g melten caprolactam (purity of caprolactam ≧95%, moisture ≦1%) and stir at 100° C. for 30 min to make AgNO3 and cetyltrimethylammonium bromide fully dissolved. When stirring, rapidly add 1 g NaOH and keep at constant temperature of 100° C. for 2 h, and then add 2 g NaBH for continued reaction for 1 h. Wash the obtained mixture with 200 g deionized water by centrifugation for three times, and obtain nano-Ag powder after intensive drying and crushing.
Add 4.24 g AgNO3 and 10 g glass microspheres (mean diameter is about 15 um) into 100 g melten caprolactam (purity of caprolactam ≧80%, moisture ≦20%) and stir at 100° C. for 1 h to make glass microspheres fully dispersed. When stirring, rapidly add 1 g NaOH and keep at constant temperature of 100° C. for 30 min. and then add 2 g glucose for continued reaction for 12 h. Wash the obtained mixture with 200 g deionized water by centrifugation for three times, and obtain nano-Ag plated glass microspheres after intensive drying and crushing. The nano-Ag plated glass microspheres can be used as an antibacterial component to be added in polymers and metals and as an electricity and heat conductive filler to be added in plastic and rubber.
Add 6.242 g CuSO4.5H2O into 100 g melten caprolactam (purity of caprolactam ≧80%, moisture ≦90%) and stir at 100° C. for 30 min to make CuSO4.5H2O fully dissolved. When stirring, rapidly add 1 g NaOH and keep at constant temperature of 120° C. for 2 h, and then add 4 g ascorbic acid for reaction for 12 h. Wash the obtained mixture with 200 g deionized water by centrifugation for three times, and obtain nano-Cu powder after intensive drying and crushing.
Add 5.0 g PdCl2 and 10 g activated carbon (carrier) into 100 g melten caprolactam (purity of caprolactam ≧80%, moisture ≦20%) and stir at 100° C. for 30 min to make PdCl2 fully dissolved. When stirring, rapidly add 1 g NaOH and keep at constant temperature of 100° C. for 2 h, and then add 2 g KBH4 for continued reaction for 2 h. Wash the obtained mixture with 200 g deionized water by centrifugation for three times, and obtain activated carbon loaded nano-Pd after intensive drying and crushing. This activated carbon loaded nano-Pd has high catalytic activity in hydrogenation reduction of nitrobenzene-containing compounds to aminobenzene compound, and in catalytic hydrogenation of paranitrotoluene to produce 4-methylaniline, the conversion rate is 90% and the selectivity is 98%.
Add 8.2 g FeCl3.6H2O into 100 g melten caprolactam (purity of caprolactam ≧95%, moisture ≦1%) and stir at 80° C. for 30 min, add 5 g deionized water for hydrolysis reaction at 100° C. for 24 h, and then vacuumize to remove water and shift to crystallization at 180° C. for 8 h. Wash the obtained mixture with 200 g absolute alcohol by centrifugation for three times, and obtain nano-Fe2O3 powder after intensive drying and crushing.
Add 6.4 g AlCl3 into 100 g melten caprolactam (purity of caprolactam ≧99.5%, moisture ≦0.1%) and stir at 80° C. for 30 min, slowly add 10 g deionized water for hydrolysis reaction at 100° C. for 24 h, and then vacuumize to remove water and shift to crystallization at 150° C. for 24 h. Wash the obtained mixture with 200 g absolute alcohol by centrifugation for three times, and obtain nano-Al(OH)3 powder after intensive drying and crushing. The powder is composed of irregular flaky particles of 2 nm in thickness.
Add 6 g tetraethyl orthosilicate into 100 g melten caprolactam (purity of caprolactam ≧60%, moisture ≦30%) and stir at 150° C. for 30 min, add 20 g deionized water for hydrolysis reaction at 120° C. for 5 h, and then vacuumize to remove water and shift to crystallization at 200° C. for 24 h. Wash the obtained mixture with 200 g absolute alcohol by centrifugation for three times, and obtain nano-SiO2 powder after intensive drying and crushing, with the size of 50 nm.
Add 6 g tetraethyl orthosilicate into 100 g melten caprolactam (purity of caprolactam ≧60%, moisture ≦30%) and stir at 150° C. for 30 min, add 0.1 g deionized water for hydrolysis reaction at 120° C. for 5 h, and then vacuumize to remove water and shift to crystallization at 200° C. for 24 h. Wash the obtained mixture with 200 g absolute alcohol by centrifugation for three times, and obtain nano-SiO2 powder after intensive drying and crushing, with the size of 12 nm.
Add 6 g tetraethyl orthosilicate into 100 g melten caprolactam (purity of caprolactam ≧60%, moisture ≦30%) and stir at 150° C. for 30 min, add 40 g deionized water for hydrolysis reaction at 120° C. for 5 h, and then vacuumize to remove water and shift to crystallization at 200° C. for 24 h. Wash the obtained mixture with 200 g absolute alcohol by centrifugation for three times, and obtain nano-SiO2 powder after intensive drying and crushing, with the size of 80 nm.
Add 5 ml butyl titanate into 100 g melten caprolactam (purity of caprolactam ≧99.5%, moisture ≦0.1%) and stir at 80° C. for 30 min, add 5 g deionized water for hydrolysis reaction at 100° C. for 24 h. and then vacuumize to remove water and shift to crystallization at 200° C. for 5 h. Wash the obtained mixture with 200 g absolute alcohol by centrifugation for three times, and obtain nano-TiO2 powder after intensive drying and crushing.
Add 3.2 g carbonyl iron into 100 g melten caprolactam (purity of caprolactam ≧99.5%, moisture ≦0.1%) and stir at 150° C. for 30 min to make it fully dissolved, add 5 g glucose, and increase the temperature to 270° C. for reflux reaction for 2 h. Wash the obtained mixture with 200 g absolute alcohol by centrifugation for three times, and obtain nano-Fe3O4 powder after intensive drying and crushing, with the size of 4 nm and the saturation magnetization of 65 emu/g.
Add 2.2 g zinc acetate and 2.4 g tetramethylthiuram disulfide (donor of anion S2−) into 100 g melten caprolactam (purity of caprolactam ≧90%, moisture ≦1%) and stir at 150° C. for 30 min to make it fully dissolved, and increase the temperature to 270° C. for reflux reaction for 2 h. Wash the obtained mixture with 200 g absolute alcohol by centrifugation for three times, and obtain nano-ZnS powder after intensive drying and crushing.
Add 1 g TiCl4 and 1.4 g trioctyiphosphine oxide (donor of anion O2−) into 100 g melten caprolactam (purity of caprolactam ≧99.5%, moisture ≦0.01%) and stir at 80° C. for 30 min to make them fully dissolved, and increase the temperature to 270° C. for reflux reaction for 2 h. Wash the obtained mixture with 200 g absolute alcohol by centrifugation for three times, and obtain nano-TiO2 powder after intensive drying and crushing.
Add 4.24 g AgNO3 into 100 g metlen caprolactam (purity of caprolactam ≧99.5%, moisture ≦0.01%) and stir at 80° C. for 30 min to make AgNO3 fully dissolved, add 5 g glucose, and increase the temperature to 200° C. for reaction for 12 h. Wash the obtained mixture with 200 g absolute alcohol by centrifugation for three times, and obtain nano-Ag powder after intensive drying and crushing.
The above descriptions of the embodiments are to help ordinary technicians in this technical field understand and apply this invention. The technicians skilled in the field can readily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the embodiments herein, and the improvement and modifications within the scope of this invention made by the technicians in this field according to the disclosure of this invention should be within the protection scope of this invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 201210014380.5 | Jan 2012 | CN | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/CN2012/070568 | 1/19/2012 | WO | 00 | 7/17/2014 |
