CN113122023A

CN113122023A - Method for preparing pigment and filler for composite material by using black talc

Info

Publication number: CN113122023A
Application number: CN202110426232.3A
Authority: CN
Inventors: 尚志新; 邱瑜; 曾泽玲; 李湘海
Original assignee: Hunan Xintianyuan New Material Co ltd
Current assignee: Hunan Xintianyuan New Material Co ltd
Priority date: 2021-04-20
Filing date: 2021-04-20
Publication date: 2021-07-16

Abstract

The embodiment of the invention provides a method for preparing a pigment and filler for a composite material by using black talc, which comprises the following steps: performing primary processing on the black talc raw ore, wherein the primary processing step comprises the steps of performing coarse crushing on the black talc raw ore and performing magnetic separation on the coarse crushed black talc raw ore; carrying out ultrafine grinding on the magnetically separated black talc raw ore by an ultrafine grinding device, wherein the particle size of the ultrafine ground black talc is between 800 and 12500 meshes; physically modifying the ultrafine-crushed black talcum powder in a grinding cavity of ultrafine crushing equipment to obtain pigment and filler; and chemically modifying the pigment and filler by a modification device to obtain the modified pigment and filler. The technical scheme of the invention solves the difficult problems in the coating industry and truly realizes the green high-added-value utilization of the black talc.

Description

Method for preparing pigment and filler for composite material by using black talc

Technical Field

The invention belongs to the field of mineral material deep processing, and particularly relates to a method for preparing a pigment filler for a composite material by using black talc.

Background

The black talc is one of industrial talcs in China, and is black due to the fact that a graphene-like lamellar structure exists between molecular layers. The black talc is a layered magnesium silicate mineral, and has Mohs hardness of 1-1.5, stable chemical property, high temperature resistance, and acid and alkali corrosion resistance. The black talc mainly comprises talc, quartz, calcite, dolomite and organic carbon, and comprises magnesium oxide, silicon nitride, calcium oxide, aluminum oxide, and small amount of iron oxide, sodium oxide, titanium oxide, etc. The reserves of black talc in China are extremely rich, the reserves are proved to be 6-8 hundred million tons in China, and 90 percent of reserves are distributed in Liaoning province, Shandong province, Guangxi province, Hunan province, Jiangxi province, Qinghai province and the like.

The application range of the black talc is greatly limited due to low whiteness, and the black talc is mainly used for producing high-grade ceramic and glaze fabric by carrying out superfine grinding after high-temperature calcination and whitening. However, the method has high energy consumption and low added value of products, and cannot realize full utilization of black talc resources. However, black and gray products in the paint and plastics industries require the addition of additional black pigments while using large amounts of high white talc.

Disclosure of Invention

The inventors of the present invention found through research that: according to the physical and chemical characteristics of the black talc ore, the black graphene structure in the black talc ore can be fully excited by a proper processing means, the coloring and reinforcing properties of the black talc ore are improved, and the method is an effective scheme for realizing the high-added-value green application of the black talc ore.

In consideration of comprehensive utilization of the black talc, the invention provides a method for preparing a pigment and filler for a composite material by using the black talc.

In the technical solution of the present invention, the inventors of the present invention recognized that: the black talc contains a graphene-like structure, and thus the color thereof is black or gray. The black graphene-like structure is sandwiched between talc layers, and is very stable in combination with talc, and the talc is also a common inorganic filler for composite materials. Thus, black talc has the potential for producing pigments and fillers for composite materials.

The method can prepare the pigment and the filler by a proper production process according to the mineral characteristics of the black talc (namely the pigment and the filler prepared by the method have the functions of pigment and filler), realize the green high-value utilization of the black talc, have good technical universality and can comprehensively utilize different types of black talc.

According to one aspect of the present invention, there is provided a method for preparing a pigment and filler for composite materials using black talc, the method comprising some of three steps of raw ore primary processing, ultra-fine pulverization, physical modification and chemical modification:

(1) the primary processing of the raw ore mainly comprises four steps of water washing, screening, coarse crushing and magnetic separation. The water washing is to wash away silt and floating dust on the surface of the black talc by water. The screening is to manually remove associated minerals such as quartz, calcite, dolomite, magnetite and the like. The coarse crushing is to crush the raw ore to 80-200 meshes by using coarse crushing equipment. And the magnetic separation is to remove the particles with higher iron content in the coarsely crushed materials by using a magnetic separator.

(2) Ultra-fine grinding: ultrafine grinding and grading equipment is selected to grind the primarily processed materials to a certain fineness to obtain ultrafine black talcum powder which can be used in the fields of paint, rubber and plastics.

(3) Physical modification: under the physical and chemical action of a small amount of adhesive assistant and mechanical force, a certain amount of physical modifier is uniformly mixed with the superfine black talcum powder and is tightly combined to obtain the pigment filler which can be used in the fields of paint, rubber and plastics.

(4) Chemical modification: and (3) selecting a proper modifier and dosage by utilizing modification equipment, and chemically modifying the physically modified sample to prepare the modified pigment filler, which can be used in the fields of coatings, rubber and plastics.

According to the method, the production processes related to the method are all pure physical processes, and the processes of strong acid, strong alkali, high pressure and the like are not related, so that the production process is safe, green and environment-friendly, no three wastes are discharged, and the adaptability to different types of black talc is high. The pigment and filler produced by the method of the invention has the advantages of uniform dispersion, good affinity with resin and excellent coloring effect, and can be widely applied to the fields of paint, rubber and plastics. The technical scheme of the invention solves the difficult problems in the coating industry and truly realizes the green high-added-value utilization of the black talc.

In order to make the aforementioned objects, features and advantages of the present application more comprehensible, preferred embodiments accompanied with figures are described in detail below.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained from the drawings without inventive effort. Wherein:

in order to more clearly illustrate the technical solutions of the embodiments of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and detailed embodiments, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without inventive labor; wherein:

fig. 1 is a flow chart of a method for preparing a pigment and filler for composite materials by using black talc according to an embodiment of the present invention.

Detailed Description

The technical scheme of the invention is further specifically described by the following embodiments and the accompanying drawings. In the specification, the same or similar reference numerals denote the same or similar components. The following description of the embodiments of the present invention with reference to the accompanying drawings is intended to explain the general inventive concept of the present invention and should not be construed as limiting the invention.

Embodiments of the present invention provide a method for preparing a pigment and filler for a composite material using black talc, the method including:

the coarse crushing in the primary processing of the raw ore is a step of coarsely crushing the screened black talc by coarse crushing equipment, wherein the coarse crushing equipment comprises any one of a hammer crusher, a cone crusher, a back-impact crusher, a roller press, a vertical mill and a Raymond mill or any combination of the hammer crusher, the cone crusher, the back-impact crusher and the roller press.

In addition, after the step of coarsely pulverizing the black talc, the method further comprises the step of magnetically separating the coarsely pulverized black talc, wherein the magnetically separated iron-rich material is used as a cement raw material, and the magnetically separated black talc is used for subsequent ultrafine processing.

Preferably, the step of subjecting the coarsely pulverized black talc to magnetic separation is performed by a dry magnetic separator having a magnetic field strength in the range of 0.02 to 2.0T, preferably 0.1 to 1.5T, more preferably 0.5 to 1T.

In one example, the step of ultra-finely pulverizing the magnetically separated black talc is performed by an ultra-fine pulverizing apparatus. The ultrafine grinding equipment comprises any one of a ring roller mill, a mechanical mill, a ball mill, an air flow mill, a steam mill, a hot air flow mill, a stirring mill and a sand mill or any combination thereof. The grading equipment is a multi-rotor or single-rotor centrifugal classifier and is used for grading and screening the black talc after the ultrafine grinding; the particle size of the black talc after the ultrafine grinding is between 800-12500 meshes, preferably 8000 meshes or 10000 meshes.

In one example, after the step of ultrafine grinding, the method further comprises the step of physically modifying the ultrafine ground black talc powder, so that the pigment and filler with controllable color, excellent reinforcing effect and excellent corrosion resistance is obtained.

In addition, the physical modification is completed in a grinding cavity of the ultrafine grinding equipment.

Preferably, the physical modification is to feed the physical modifier, the bonding auxiliary agent and the pre-processed material into a grinding cavity together for crushing and uniformly mixing; the physical modifier comprises any one or more of red lead, strontium chrome yellow, zinc chrome yellow, barium chrome yellow, calcium chrome yellow, phosphate, phosphomolybdate, aluminum dihydrogen tripolyphosphate, zinc molybdate, zinc borate, mica iron oxide, titanium dioxide, nano zinc oxide, graphite, ultramarine, phthalocyanine blue, barium sulfate, iron oxide red, iron black, barium sulfate and the like; the physical modifier is 0-60% (such as 0.5-30%, or 5-20%) of the mass of the black talcum powder; the bonding auxiliary agent is sodium silicate, potassium silicate, a bis-silane coupling agent and the like; the bonding auxiliary agent is 0-10% (such as 0.5-8%, or 1-5%) of the mass of the black talcum powder.

In one example, after the step of physically modifying the black talc, the method further comprises chemically modifying the black talc to obtain a modified pigment filler.

Further, the step of chemically modifying is performed by a modifying apparatus.

Preferably, the modifying equipment comprises any one of a three-roll modifying machine, a high-speed stirrer and a tower-type modifying machine or any combination thereof, and the modifying agent used for chemical modification is any one of a silane coupling agent, an aluminate coupling agent, a titanate coupling agent, a rare earth coupling agent, fatty acid and salt thereof, a polyalcohol substance, higher alcohols, ammonium polyacrylate, sodium hexametaphosphate and sodium tripolyphosphate or any combination thereof; the dosage of the modifier is 0.01-25% (such as 10% or 15%) of the mass of the ultrafine-ground black talc powder; the temperature range for the surface modification is 50-300 deg.c (e.g., 200 deg.c).

In embodiments, the composite material is rubber, paint or plastic.

Several specific examples are provided below to illustrate the steps of the method of the present invention in detail, and it is obvious that the technical solution of the present invention is not limited to the examples provided below.

Example 1

The raw material of black talc from Guangfeng ore in Jiangxi is in block shape, and the main chemical composition is shown in Table 1. In this example, the processing techniques used were water washing, sieving, coarse pulverization, ultra-fine pulverization, physical modification, and chemical modification. The specific preparation process parameters are as follows: washing off dust on the surface of the black talc by tap water, manually selecting and removing associated minerals, naturally drying, crushing raw black talc powder to below 20mm by using a jaw crusher, and coarsely crushing by using a Raymond mill to 200 meshes. Adding 1% of strontium chrome yellow and 0.1% of sodium silicate into the coarsely crushed material, and performing ultrafine crushing and physical modification by using a fluidized bed type airflow mill at the pressure of 0.9Mpa and the rotating speed of a grader of 2500rpm to obtain a pigment filler A1; and finally, continuously stirring the part of the materials after the ultrafine grinding for 15 minutes (min) at 120 ℃ by using a high-speed stirrer and 1 percent of silane coupling agent (KH560) as a modifier to prepare the modified pigment and filler A2, wherein the particle size distribution of the modified pigment and filler is shown in Table 2.

TABLE 1 chemical composition of materials

TABLE 2 particle size distribution of different fillers

Example 2

The black talc of Heidede ore in Hunan province was a bulk material, and its main chemical composition was as shown in Table 3. In this example, the processing techniques used were water washing, sieving, coarse crushing, magnetic separation, ultra-fine crushing, physical modification and chemical modification. The specific preparation process parameters are as follows: washing off dust on the surface of the black talc by tap water, manually selecting and removing associated minerals, naturally drying, crushing raw black talc powder to below 20mm by using a jaw crusher, and coarsely crushing the powder to 200 meshes by using a vertical mill. After the coarse crushing is finished, the black talc coarse powder is subjected to magnetic separation for 2 times by using a dry magnetic separator under the magnetic field intensity of 1.4T so as to reduce the iron content in the black talc. Mixing the magnetically-separated material with 0.5% nanometer zinc oxide, and performing ultrafine grinding and physical modification by steam grinding at 190 deg.C under 1.2Mpa to obtain pigment and filler B1 (particle size distribution shown in Table 4). Finally, the physically modified material is subjected to chemical modification by a three-roll modification machine at 100 ℃ by using a silane coupling agent (Si69) with the mass fraction of 0.5% and a silane coupling agent (KH540) with the mass fraction of 0.5%, so as to prepare the modified pigment filler B2, wherein the particle size distribution of the modified pigment filler B2 is shown in Table 4.

TABLE 3 chemical composition of materials

TABLE 4 particle size distribution of different fillers

Example 3:

using pigment filler B1 and modified pigment filler B2 prepared in example 2, filling experiments were conducted in styrene-butadiene rubber and performance comparisons were made with commercially available 2500 mesh white talc (2200 RMB/ton). The rubber formula is as follows: styrene butadiene rubber (100 parts), stearic acid (1 part), sulfur (1.75 parts), zinc oxide (3 parts), accelerator NS (1 part), pigment and filler B1 or modified pigment and filler B2 or 2500-mesh white talc (40 parts). The raw materials in the formula are sequentially added into an internal mixer to be uniformly mixed by adopting a 1-stage mixing process, then a triangular bag is formed in an open mill for 3 times and is thinly passed through for 3 times, after the mixture is placed for 6 hours (h), a flat vulcanizing instrument is used for vulcanizing for 17min under the pressure of 15MPa, and the performance index is tested after the mixture is vulcanized, formed and placed for 24 hours. Specific performance indexes are shown in table 5:

TABLE 5 filling Properties comparison Table

Example 4:

using the pigment filler A1 and the modified pigment filler A2 prepared in example 1, filling experiments were carried out in PVC and the properties were compared with commercially available 2500 mesh white talc (2200 yuan/ton). The PVC formula is as follows: PVC (100 parts), calcium stearate (1 part), composite lead (8 parts), stearic acid (2 parts), paraffin wax (2 parts), CPE (4 parts), CPR (1.5 parts), white talc (50 parts), carbon black (0.8 part) or pigment and filler A1(50 parts) or modified pigment and filler A2(50 parts). After statically heating the high-speed stirring machine to 150 ℃, pouring the prepared PVC and the auxiliary agent into a high-speed stirring machine, mixing and stirring for 15min, removing water in the materials, adding the filler, mixing, discharging, extruding the dried mixed materials by an extruder (the extrusion temperature is 155-170 ℃), cooling in water, crushing in a crusher, drying the obtained particles in an oven at 70 ℃ for 8h, injecting the particles into a standard sample strip in an injection molding machine at 200 ℃ and carrying out performance test. Specific performance indexes are shown in table 6:

TABLE 6 comparison of filling properties of different types of fillers

Example 5:

using the pigment filler a1 and the modified pigment filler a2 prepared in examples 1 and 2, a comparative experiment was performed in gray anticorrosive water-borne coatings with the commonly used pigment filler system (carbon black + titanium white + white talc). The coating formulation and property pairs are shown in table 7:

TABLE 7 Grey anticorrosive water-based paint formula, paint preparation process and performance comparison

It is obvious from the five embodiments that the composite pigment and filler prepared by the method of the invention successfully excites the graphene-like structure between the layers of the black talc, and can play double roles of pigment and filler. The pigment and the filler in the invention can completely replace white talc with the same fineness in rubber products, and can play double roles of pigment and filler in deep color coatings and plastics, thereby respectively replacing a common white talc-titanium dioxide-carbon black system and a common white talc-carbon black system. The method of the invention can not only reduce the production cost of rubber, plastic and paint, but also improve the product performance, and really realize the high value-added utilization of the black talc. The method has obvious environmental protection significance and economic benefit and wide market prospect.

Although a few embodiments of the present general inventive concept have been shown and described, it will be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the general inventive concept, the scope of which is defined in the appended claims and their equivalents.

Claims

1. A method of making a pigment filler for composite materials using black talc, the method comprising:

performing primary processing on the black talc raw ore, wherein the primary processing step comprises the steps of performing coarse crushing on the black talc raw ore and performing magnetic separation on the coarse crushed black talc raw ore;

carrying out ultrafine grinding on the magnetically separated black talc raw ore by an ultrafine grinding device, wherein the particle size of the ultrafine ground black talc is between 800 and 12500 meshes;

physically modifying the ultrafine-crushed black talcum powder in a grinding cavity of ultrafine crushing equipment to obtain pigment and filler;

and chemically modifying the pigment and filler by a modification device to obtain the modified pigment and filler.

2. The method of claim 1, wherein,

the modification equipment comprises any one of a three-roll modification machine, a high-speed stirrer and a tower-type modification machine or any combination thereof.

3. The method of claim 2, wherein,

the modifier used for chemical modification is any one or any combination of a silane coupling agent, an aluminate coupling agent, a titanate coupling agent, a rare earth coupling agent, fatty acid and salts thereof, polyalcohol substances, higher alcohols, ammonium polyacrylate, sodium hexametaphosphate and sodium tripolyphosphate; the dosage of the modifier is 0.01 to 25 percent of the mass of the ultrafine crushed black talcum powder; the temperature range of the chemical modification is 50-300 ℃.

4. The method of any one of claims 1-3,

the physical modification is that the physical modifier, the bonding auxiliary agent and the pre-processed black talc raw ore material are put into a superfine grinding device to be ground and mixed.

5. The method of claim 4, wherein,

the physical modifier comprises any one or more of red lead, strontium chrome yellow, zinc chrome yellow, barium chrome yellow, calcium chrome yellow, phosphate, phosphomolybdate, aluminum dihydrogen tripolyphosphate, zinc molybdate, zinc borate, mica iron oxide, titanium dioxide, nano zinc oxide, graphite, ultramarine, phthalocyanine blue, barium sulfate, iron oxide red, iron black and barium sulfate;

the physical modifier is 0-60% of the mass of the black talcum powder;

the bonding auxiliary agent is sodium silicate, potassium silicate and a bis-silane coupling agent;

the adhesive auxiliary agent accounts for 0-10% of the mass of the black talcum powder.

6. The method of claim 5, wherein,

the ultrafine grinding equipment comprises any one of a ring roller mill, a mechanical mill, a ball mill, an air flow mill, a steam mill, a hot air flow mill, a stirring mill and a sand mill or any combination thereof;

and screening the ultrafine crushed black talcum powder by a grading device to obtain the particle size of 800-12500 meshes.

7. The method of claim 6, wherein,

8. The method of claim 7, wherein,

after the step of coarsely crushing the black talc, the method further comprises the step of carrying out magnetic separation on the coarsely crushed black talc, wherein the magnetically separated iron-rich material is used as a cement raw material, and the magnetically separated black talc is used for subsequent superfine processing.

9. The method of claim 8, wherein,

the step of magnetically separating the coarsely pulverized black talc is performed by a dry magnetic separator having a magnetic field strength ranging from 0.02 to 2.0T.

10. The method of claim 9, wherein,

the composite material comprises rubber, paint or plastic.