CN1371946A

CN1371946A - Surface nano modifying method for micrometer granule

Info

Publication number: CN1371946A
Application number: CN 01104496
Authority: CN
Inventors: 盖国胜; 樊世民; 徐杭庆
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-02-27
Filing date: 2001-02-27
Publication date: 2002-10-02
Anticipated expiration: 2021-02-27
Also published as: CN1263808C

Abstract

The method for modifying surface of micrometer-level granules by adopting nano granules is characterized by that the small quantity of nano granules can be uniformly dispersed on the surface of large quantity of micrometer granules so as to obtain the composite granules material whose micrometer granules are covered with nano granules. The micrometer granule material can be calcium carbonate, wollastonite and talcum, etc. and nano granule material can be calcium carbonate, dsilicon dioxide, titanium dioxide and white carbon black, etc. It can be extensively used in fileds of paper-making rubber, plastics and coating industries.

Description

A kind of surface nano modifying method for micrometer granule

The present invention is a kind of novel method that adopts nano particle micron particles to be carried out surface modification.

The yardstick of nano particle is commonly defined as 1～100nm.Its yardstick is greater than elementide (cluster), and less than common particulate (fine partical).When low particle size enters the nanometer quantum stage, mainly has the effect of following three aspects: one, small-size effect.When physical features sizes such as the coherence length of particle size and optical wavelength, de broglie wavelength and superconducting state or transmission depth quite or more hour, periodic final condition is with destroyed; Two, surface and interfacial effect.Nanoparticle size is little, and the surface is big, and the atom that is positioned at the surface accounts for sizable ratio, along with grain through reducing, it is big that the surface sharply becomes, causing that the surface atom number increases sharply has increased the activity of nanoparticle greatly; Three, quantum size effect.The energy level of electronics maybe can have confidential relation with the particle with composition material in the material, promptly when size of particles drops to certain value near the electronic level the fermi level by the quasi-continuous discrete energy level phenomenon that becomes.These effects of nano particle cause performances such as its electricity, magnetic, heat, light, sensitivity characteristic and surface stability obviously to be different from common particle, thereby it is had broad application prospects.But the preparation cost of nano particle is quite expensive, and this becomes a bottleneck in its application.Nano particle is huge owing to surface-area in addition, and surface energy is very high, the very easy second particle that is agglomerated into, and dispersiveness is difficult to be well solved.

The present invention is exactly in conjunction with the low cost of micron particle and the high-performance of nano particle, adopts novel method to make the composite particles of nano particle coating micron particle.Promptly utilize a spot of nano particle (low cost) to reach the making Nano surface of a large amount of micron particle.Simultaneously nano particle is again at micron particle surface homodisperse, thereby makes the dispersion problem of nano particle obtain to a certain degree improvement.

The preparation process of nano particle among the present invention-micron particle composite particles is in the suspension of certain density micron particle, under the effect of mechanical stirring power, adds a certain proportion of nano particle and property-modifying additive.Behind the effect certain hour, filtration, drying, dispersion can obtain nano particle-micron particle composite particles under certain temperature.This composite particles can be described as the inorganic coated fertilizer of powder again, can improve the surface imperfection of nonmetalliferous ore powder effectively, can make composite inorganic coat the material premium properties again and be given full play to, so this matrix material is the novel powder material with functional performance.Along with the development of modern novel high polymer material, functional composite material and ceramic, the demand of the inorganic nonmetal mineral fillers of process surface modification treatment is with sustainable growth.The consumption of surface treated mineral filler in plastics industry only according to estimates from now on will be with the speed increase in every year about 15%.As seen this inorganic non-metallic film-coating technique has a extensive future at development functional mineral surface side filler

The preparation process of nano particle among the present invention-micron particle composite particles, wherein controllable parameter mainly contains: the 1. concentration of micron particle and particle diameter; 2. the addition of nano particle and particle diameter; 3. the size of mechanical stirring power, the i.e. size of stirring velocity; 4. the kind of property-modifying additive and quantity; 5. environmental system temperature, action time.

The preparation process of nano particle among the present invention-micron particle composite particles, micron particle can be particles such as lime carbonate, wollastonite, talcum, and nano particle can be lime carbonate, silicon-dioxide, titanium dioxide, white carbon black etc.The particle diameter of micron particle is 1～30 μ m, and concentration requirement mainly is will be easy to form stabilized uniform suspension, is generally 10～40%.The particle diameter of nano particle can be 10～80nm, and addition is 1～5%.

The preparation process of nano particle among the present invention-micron particle composite particles, additive is chosen suitable kind and quantity according to different granulometric composition.Kind has silane coupling agent, titanate coupling agent, aluminate coupling agent, lipid acid and salt thereof etc., and addition is 0.5～3%.

The preparation process of nano particle among the present invention-micron particle composite particles, stirring velocity are 1000～3000rpm, change according to the particle different-grain diameter.System temperature is 0～80 ℃, and be 10～180min action time.

Example one:

Adopt 2000g wollastonite particle, its median size is 5 μ m.It is dissolved in the water of 5000ml, and low whipping speed is to be made into suspension under the whipping force effect of 1500rpm, and solution temperature is controlled at 50 ℃.Nano particle is a nano-calcium carbonate, and its median size is 50nm, and addition is 3%.Property-modifying additive is stearic acid and silane coupling agent, and total amount is 1%.Be 60min action time.Filtration then, drying, dispersion can obtain nano-calcium carbonate-micron wollastonite composite particles.The surface of wollastonite is coating nano-calcium carbonate equably, and clad ratio is more than 85%.

Example two:

Adopt the 2000g calcium carbonate granule, its median size is 15 μ m.It is dissolved in the water of 5000ml, and low whipping speed is to be made into suspension under the whipping force effect of 2000rpm, and solution temperature is controlled at 50 ℃.Nano particle is a nano-calcium carbonate, and its median size is 50nm, and addition is 2%.Property-modifying additive is stearic acid and silane coupling agent, and total amount is 0.5%.Be 60min action time.Filtration then, drying, dispersion can obtain nano-calcium carbonate-micron wollastonite composite particles.The surface of wollastonite is coating nano-calcium carbonate equably, and clad ratio is more than 80%.

Claims

1. the present invention is a kind of novel method that adopts nano particle micron particles to be carried out surface modification.This method has made the composite particles of nano particle coating micron particle in conjunction with the low cost of micron particle and the high-performance of nano particle.Its essential characteristic is:

1. adopt mechanical crushing method to make micron particles, adopt chemical process to make nano particle;

2. micron particles is dissolved in the solvent, under the effect of mechanical stirring power, be made into certain density suspension, and hierarchy of control temperature is to claimed range;

3. the certain amount of nano particle is added solution, add a certain amount of property-modifying additive simultaneously, the effect certain hour;

4. solution filtration, drying, dispersion are promptly got the composite particles that nano particle coats micron particle.

2. according to method in the claim 1, micron particle can be particles such as lime carbonate, wollastonite, talcum, and median size is at 1～30 μ m.Nano particle can be lime carbonate, silicon-dioxide, titanium dioxide, white carbon black etc., and median size is 10～80nm.

3. according to method in the claim 1, additive can be silane coupling agent, titanate coupling agent, aluminate coupling agent, lipid acid and salt thereof etc., and addition is 0.1～3%.

4. according to method in the claim 1, stirring velocity is controlled at 1000～3000rpm.

5. according to method in the claim 1, system temperature is controlled at 0～80 ℃, and be 10～180min action time.