CN101174496A

CN101174496A - Production method for barite composite conducting material

Info

Publication number: CN101174496A
Application number: CNA200710035918XA
Authority: CN
Inventors: 杨华明
Original assignee: Central South University
Current assignee: Central South University
Priority date: 2007-10-17
Filing date: 2007-10-17
Publication date: 2008-05-07
Anticipated expiration: 2027-10-17
Also published as: CN100520989C

Abstract

The invention discloses a method for preparing barite compound conductive material, which is characterized in that: high-purity barites are ball milled to 0.5 to 5.0 Mum of the particle size through method of powders prepared by wet chemical, the barite powders are put in distilled water after being filtered, dried and grinded, simultaneously, polyethylene glycol is added as dispersing agent; the NH4F solution and the SnCl4 4H2O ethanol solution are mutually dissolved with each other, then, the solution is dropped in the distilled water of the barite powders, the quantity of materials is controlled as F: Sn 1:99 to 50:50, simultaneously, the pH value is controlled as 3 to 5, the reaction temperature is 20 to 60 DEG C, then be roasted after being stirred, air pump filtrated and dried. The invention has the advantages that the metal oxide coats on the barite surface more uniformly, the obtained compound conductive material is low colored, the conductibility is more stable, the dispersity is strong and the application performance is greater.

Description

A kind of preparation method of barite composite conducting material

Technical field

The present invention relates to the preparation of mineral, relate in particular to the preparation method of barite composite conducting material as the composite conducting material of matrix.

Background technology

Composite conducting material is to be matrix with light weight, material inexpensive, that look shallow, forms the conductivity oxide layer or handles with semiconductor doping at matrix surface by chemically composited, and make the dusty material that a class has conducting function.This class composite conducting material is according to the difference of matrix, can be divided into conductive mica powder, conductive titanium dioxide, conduction barium sulfate and conduction silicon dioxide etc., its outward appearance generally is canescence or light grey powder, has characteristics such as look shallow, good conductivity, stability is high, heat-resisting, corrosion-resistant, cost is low.Also can cooperate with other pigment, make versicolor permanent conduction, anti-static coatings such as near-white, can be widely used in conduction, the antistatic field of each industrial departments such as oil, chemical industry, building materials, electronics, electromechanics, automobile, medicine and people's daily life.

The composite conducting material of existing barite matrix mainly contains two classes: a class is to make matrix by 325 order blanc fixes, passes through SnCl ₄And SbCl ₃Hydrolysis, filter, the oven dry back is at 750 ℃ of calcining 30min down control pH=1.5～2.0, preparation barite surface coats antimony (Sb) doping SnO ₂Barite composite conducting material; Another kind of is to make matrix by 300 order blanc fixes, passes through SnCl ₄, SnCl ₂With NH ₄The hydrolysis of F, back calcining 60min under 250～500 ℃ is filtered, dried in control pH=0.5～2.5, surperficial fluorine (F) the doping SnO that coats of preparation barite ₂Barite composite conducting material (FSB).

The barite matrix granularity excessive (40～44 μ m) that these two kinds of methods are used, the composite conducting material particle diameter of formation is big, the result of use of influence in electrically-conducting paint, conductive coating; The 2nd, the solution chemistry reaction pH value is lower, all less than 2.5, can influence hydrolysis rate in the practical operation, causes product to be difficult for being difficult to reach the effect of even coating in the barite surface adsorption; The 3rd, degree of scatter is not enough in the hydrolysis, also can influence reaction process and product property.In addition, among the existing FSB preparation method, because sintering temperature low (less than 500 ℃) influences SnO in the formed coating layer ₂The crystalline form integrality, thereby cause the stability of powder serviceability not high.

Summary of the invention

The objective of the invention is to improve existing FSB preparation method, make the FSB material color for preparing shallow, electric conductivity is more stable, and dispersed strong, application performance is better; And in the method, can obtain FSB electric conducting material by adjusting different bar ratios with different conductivity.

Detailed protocol of the present invention is: with high-purity barite powder wet ball grinding to particle diameter is 0.5～5.0 μ m, and after filtration, dry and grind, getting blanc fixe, to place distilled water to make its solid content be 30%, adds 0.5% polyethylene glycol simultaneously and makes dispersant; NH with 20% ₄The SnCl of the F aqueous solution and 0.2mol/L ₄4H ₂The ethanolic solution of O dissolves each other, and splashes in the distilled water of barite powder, and control F: Sn (by amount of substance) is 1: 99～50: 50, and dripping 40% ammonia spirit simultaneously, to control the pH value be 3～5, and control reaction temperature is 20 ℃～60 ℃; After titration is finished, stir 0.5～1h, suction filtration, oven dry then at 600 ℃～900 ℃ following roasting 0.5～2h, obtain F doping SnO of the present invention ₂/ BaSO ₄(FSB) composite conducting material.

In the present invention, barite powder particle diameter is preferably about 2.1 μ m; The drop reaction temperature is preferably 50 ℃～60 ℃, and the reaction time is preferably 30～40min; The preferred temperature of roasting is 700 ℃～800 ℃, and roasting time is preferably 1～2h.

Among the present invention, the barite matrix of preparation conductive powder must pass through wet ball grinding in advance, and granularity is controlled in the narrower scope.In the mechanical milling process, the barite adjustable ratio, but unsuitable excessive, otherwise influence conductivity.The time of titration process finishes to best at 30～40min, otherwise can cause barite substrate surface oxide particle skewness.

Compare with the method for existing preparation FSB, the present invention has following advantage:

(1) used barite matrix granularity 0.5～5 μ m, particle diameter is little, and the composite conducting material particle diameter of preparation is less than 10 μ m, helps powder dispersed in electrically-conducting paint, conductive rubber and improves application performance;

(2) the pH value of hydrolysis is controlled at 3～5, helps accurate control on the one hand, can accelerate hydrolysis rate on the other hand, helps the even coating of metal oxide on the barite surface;

(3) add poly-ethanol during hydrolysis and make dispersant, improve the degree of scatter of solution reaction system, help reacting complete;

Sintering temperature is controlled at 600～900 ℃ when (4) preparing FSB, improves SnO in the coating layer ₂The integrality of crystalline form can be stablized the serviceability of composite conducting material.

Description of drawings

Fig. 1: the XRD figure spectrum of FSB composite conducting material;

Fig. 2: the relation of the doping of resistivity and fluorine;

Fig. 3: the relation of resistivity and different barite particle diameters.

Embodiment

Barite former state 2kg, ball milling in agitating ball mill, ball-milling medium are zirconia ball, and ball material weight ratio is 4: 1, and ratio of water to material is 1: 1, and the ball milling time is 1.5～7.5h, obtains the blanc fixe of particle diameter at 0.5～5.0 μ m.After filtration, standby after drying, the grinding.Get solid content and be the distilled water that 30% blanc fixe 30g places 100mL, add 0.5% polyethylene glycol simultaneously as dispersant, with SnCl ₄4H ₂O and NH ₄F is a raw material, default SnCl ₄4H ₂O: barite=15: 85 (mass ratio), with the SnCl of 0.2mol/L ₄4H ₂O ethanolic solution and 20% NH ₄The F aqueous solution, F: Sn (amount of substance) was respectively 1: 99,3: 97,5: 95,10: 90,30: 70 and 50: 50.In the process that constantly stirs, with SnCl ₄4H ₂O and NH ₄The mixed solution of F is added drop-wise to and fills in the bar distilled water, and dripping 40% ammonia spirit simultaneously, to control corresponding pH value be 3,60 ℃ of reaction temperatures, after question response is finished, stir 0.5～1h, suction filtration, drying, grinding, at 700 ℃ of following roasting 2h, obtain FSB composite conducting material of the present invention.

In the method for the invention, work as F: Sn presses amount of substance than=50: 50, and hydrolysis temperature is 60 ℃, pH=3, the barite particle diameter is about 2.1 μ m, and sintering temperature is 700 ℃, and the XRD figure spectrum of the FSB composite conducting material that roasting time prepares during for 2h as shown in Figure 1.

When hydrolysis temperature is 60 ℃, pH=3, barite particle diameter 2.1 μ m, sintering temperature is 700 ℃, when roasting time is 2h, the doping of fluorine is controlled to be F: Sn (amount of substance)=1: 99,3: 97,5: 95,10: 90,30: 70 and 50: 50 o'clock respectively in the preparation process, and the resistivity of the FSB composite conducting material for preparing is as shown in table 1.The graph of relation of the doping of fluorine and the resistivity of material for preparing is as seeing Fig. 2.

The relation of the resistivity of table 1 composite conducting material and fluorine doping

F: Sn (amount of substance ratio)	3∶97	5∶95	10∶90	30∶70	50∶50
F: Sn (amount of substance ratio)	3∶97	5∶95	10∶90	30∶70	50∶50	F doping (mol.%)	3	5	10	30	50
Electricalresistivity/Ω cm	1.22×10 ⁷	9.87×10 ⁶	6.94×10 ⁶	4.46×10 ⁶	1.03×10 ⁶	F doping (mol.%)	3	5	10	30	50

In the method for the invention, work as F: Sn presses amount of substance than=50: 50, hydrolysis temperature is 60 ℃, pH=3, sintering temperature is 700 ℃, when roasting time was 2h, the barite with 2.1 μ m, 2.3 μ m, 2.5 μ m, 2.9 μ m, 3.9 μ m prepared the FSB composite conducting material respectively, and the resistivity of resulting FSB composite conducting material is respectively as shown in table 2.The graph of relation of barite granularity and resistivity is seen Fig. 3.

The relation of the resistivity of table 2 composite conducting material and barite particle diameter

Barite granularity/μ m	2.1	2.3	2.5	2.9	3.9
Barite granularity/μ m	2.1	2.3	2.5	2.9	3.9	Electricalresistivity/Ω cm	1.03×10 ⁶	2.66×10 ⁶	4.00×10 ⁶	1.09×10 ⁷	2.35×10 ⁷

Claims

1. the preparation method of a barite composite conducting material, it is characterized in that: with high-purity barite powder wet ball grinding to particle diameter is 0.5～5.0 μ m, dry and grinding after filtration,, getting blanc fixe, to place distilled water to make its solid content be 30%, adds 0.5% polyethylene glycol simultaneously and make dispersant; NH with 20% ₄The SnCl of the F aqueous solution and 0.2mol/L ₄4H ₂The ethanolic solution of O dissolves each other, and splashes in the distilled water of barite powder, and control F: Sn (by amount of substance) is 1: 99～50: 50, and dripping 40% ammonia spirit control pH value simultaneously is 3～5, and controlling the drop reaction temperature is 20 ℃～60 ℃; After titration is finished, stir 0.5～1h, suction filtration, oven dry are then at 600 ℃～900 ℃ following roasting 0.5～2h.

2. the method for claim 1, it is characterized in that: described drop reaction temperature is 50 ℃～60 ℃, and the reaction time is 30～40min.

3. the method for claim 1, it is characterized in that: sintering temperature is 700 ℃～800 ℃, and roasting time is 1～2h.

4. as the method one of as described in the claim 1～3, it is characterized in that: described barite powder particle diameter is preferably about 2.1 μ m.