CN102000543A - Method for preparing inorganic montmorillonite material - Google Patents

Abstract

The invention relates to a method for preparing an inorganic montmorillonite material. The first step is to prepare sodium montmorillonite; the second step is to prepare a 0.5-4% dispersion of sodium montmorillonite, absolute ethanol and water, drying to obtain an inorganic montmorillonite film; or adding the dispersion liquid to a polyimide non-woven fabric and drying to obtain a montmorillonite-polyimide composite material. The invention has the characteristics of simple process, good experiment reproducibility, low production cost and the like; the prepared composite material has excellent fire-proof and heat-insulating properties and has good application prospects.

Description

A kind of preparation method of inorganic montmorillonite material

technical field

The invention belongs to the field of preparation of montmorillonite, in particular to a preparation method of inorganic montmorillonite material.

Background technique

Montmorillonite is a 2:1 layered mica silicate. Each unit cell is composed of two silicon-oxygen tetrahedrons with an aluminum-oxygen octahedron in the middle. The thickness of each layer is about 1nm, and Ca is adsorbed between the layers. ²⁺ , Mg ² + , Na ⁺ and other cations are easily replaced by other cations, and usually they exist in the form of hydrated cations. This hydrophilic microenvironment is not conducive to the intercalation and adsorption of lipophilic polymers or monomers. The organic cationic modifier is used for ion exchange with montmorillonite, so that the hydrophilic montmorillonite becomes lipophilic montmorillonite, and at the same time the interlayer distance is expanded, which is beneficial to the adsorption or intercalation of organic matter. It can be used in the preparation of polymer/montmorillonite nanocomposite materials, or as an adsorbent for organic matter in wastewater treatment.

In recent years, research on montmorillonite has mainly focused on composite materials. Most of them combine modified montmorillonite, intercalated montmorillonite, or exfoliated montmorillonite with another organic polymer or inorganic Composite to form synthetic materials, and then applied in many ways. Composite materials are widely used, and can be used for fireproof and heat insulation materials, as well as adsorbents, catalysts, foam materials, etc. For example, patent CN101564874 provides a preparation method of nano-insulation composite material, that is, nylon PA66, long alkali-free glass fiber, nano-titanium dioxide, and nano-montmorillonite are compounded by a certain technology, and then prepared with high tensile strength, A material with high rigidity and excellent molding stability. Patent CN1769338 provides a preparation method of polyethylene/montmorillonite nano-composite material. The montmorillonite sheet is evenly dispersed in the polyethylene matrix, and then the composite material is made by in-situ generation method. Patent CN101597392 provides a preparation method of inorganic ion/polyolefin foam material, which has good mechanical properties and low preparation cost. Patent CN101239325 provides a preparation method of montmorillonite/ZSM-5 molecular sieve composite material. The composite material has good hydrothermal stability and is mainly used in the preparation of various catalysts and adsorbents, especially hydrogenation catalysts.

Contents of the invention

The technical problem to be solved by the present invention is to provide a preparation method of inorganic montmorillonite material, which has the characteristics of simple process, good experiment reproducibility, and low production cost; the prepared composite material has excellent fireproof and heat insulation performance, and has Good application prospects.

A kind of preparation method of inorganic montmorillonite material of the present invention comprises:

(1) Preparation of sodium montmorillonite

Mix 2-5g of reagent grade pure montmorillonite, 0.2-2.2g of NaCl and 80-150ml of distilled water. The quality of NaCl is 2-6 times the cation exchange capacity of montmorillonite (CEC), react at room temperature -100°C for 2-12h, cool , centrifuged and washed until there is no Cl ^- in the supernatant;

(2) Preparation of inorganic montmorillonite film and montmorillonite-polyimide composite

The above-mentioned sodium montmorillonite is mixed with ethanol and water mixture to prepare a dispersion liquid with a weight percentage of 0.5-4%, and the dispersion is uniform, and then the pH of the dispersion liquid is adjusted to 8-13 with NaOH aqueous solution, and dried to obtain an inorganic Montmorillonite film; or add the dispersion liquid on the polyimide non-woven fabric and dry to prepare the montmorillonite-polyimide composite material.

Reagent-grade pure montmorillonite in said step (1) is replaced by sodium montmorillonite and then directly carries out step (2), and the CEC of sodium montmorillonite is 90mmol/100g, 110mmol/100g or 113mmol/100g, and the purity >90%, the particle size is 2.0-10μm.

The volume percentage of ethanol and water in the ethanol and water mixed solution in the step (2) is 25%-50%: 50-75%.

The NaOH aqueous solution concentration in the step (2) is 1M.

The specific process of uniform dispersion in the step (2) is to use an ultrasonic cell pulverizer to process the montmorillonite dispersion for 600-3200s, and the power is 600-800W.

The drying temperature in the step (2) is room temperature-60°C.

The weight percentage of montmorillonite in the montmorillonite-polyimide composite material in the step (2) is 20%-140%, and the thickness of the polyimide nonwoven material is 2-3mm.

Beneficial effect

The invention has the characteristics of simple process, good experiment reproducibility, low production cost and the like; the prepared composite material has excellent fire-proof and heat-insulating properties and has good application prospects.

Description of drawings

Fig. 1 is montmorillonite SEM, wherein, (a) is reagent grade montmorillonite; (b) is the Na-MMT that CEC is 90mmol/100g; (c) is the Na-MMT that CEC is 110mmol/100g;

Figure 2 is a pure montmorillonite film SEM, wherein (a) is the front of the pure montmorillonite film; (b) is the side of the pure montmorillonite film;

Figure 3 is a pure polyimide SEM;

Figure 4 is the SEM of the montmorillonite-polyimide composite.

Detailed ways

Below in conjunction with specific embodiment, further illustrate the present invention. It should be understood that these examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the teachings of the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of the present application.

Example 1

Put 3g of reagent grade pure montmorillonite and 0.39g NaCl, the quality of NaCl is 2.5 times that of CEC of montmorillonite, put 100ml of distilled water into a 250ml three-neck flask, react at 100°C for 6h, cool down, centrifuge and wash until there is no Sodium montmorillonite and ethanol: water (volume percentage 50%: 50%) ^are configured into 200g of a dispersion liquid with a weight percentage of 0.5%, and a cell pulverizer is used to treat the dispersion liquid at 600-800W for 1600s to make the dispersion liquid uniform , and then use 1M NaOH aqueous solution to adjust the pH value of the dispersion to 10.5, pour the dispersion into a shallow flat-bottomed container, the thickness of the dispersion is 3 mm, put it in a blast oven, and dry it at 40 ° C to make a flexible inorganic montmorillonite Soil film.

Example 2

Put 5g of reagent grade pure montmorillonite and 0.59g NaCl, the quality of NaCl is 4 times that of CEC of montmorillonite, put 100ml of distilled water into a 250ml three-neck flask, react at 80°C for 2h, cool down, centrifuge and wash until there is no Sodium montmorillonite and ethanol: water (volume percentage 50%: 50%) ^are configured into 200g of a dispersion liquid with a weight percentage of 0.5%, and a cell pulverizer is used to treat the dispersion liquid at 600-800W for 1600s to make the dispersion liquid uniform , and then use 1M NaOH aqueous solution to adjust the pH value of the dispersion to 9, pour the dispersion into a shallow flat-bottomed container, the thickness of the dispersion is 3mm, put it in a blast oven, and dry it at 40°C to make a flexible inorganic mask. Remove soil film.

Example 3

Put 2g of reagent-grade pure montmorillonite and 0.98g NaCl, the quality of NaCl is 6 times that of montmorillonite CEC, put 100ml of distilled water into a 250ml three-necked flask, react at 100°C for 6h, cool down, centrifuge and wash, and pour into the clear liquid Until there is no ^Cl- ; Sodium montmorillonite and ethanol: water (volume percentage 25%: 75%) are configured into 200g of a dispersion liquid with a weight percentage of 1%, and the dispersion liquid is dispersed by using a cell pulverizer at 600-800W for 1600s Evenly, then use 1M NaOH aqueous solution to adjust the pH value of the dispersion to 12, pour the dispersion into a shallow flat-bottomed container, the thickness of the dispersion is 2mm, put it in a blast oven, and dry it at 40°C to make a flexible inorganic Montmorillonite film.

Example 4

Put 3g reagent grade pure montmorillonite and 0.39g NaCl, the quality of NaCl is 2.5 times of montmorillonite CEC, put 100ml distilled water into a 250ml three-neck flask, react at 100°C for 12h, cool down, centrifuge and wash, and pour into the clear liquid Until there is no ^Cl- ; configure montmorillonite and ethanol: water (volume percentage 50%: 50%) into 200 g of a dispersion liquid with a weight percentage of 1.5%, and use a cell pulverizer to process the dispersion liquid at 600-800W for 600 seconds to disperse the dispersion liquid evenly. Then use 1M NaOH aqueous solution to adjust the pH value of the dispersion to 12, add the dispersion to the surface of the flat polyimide non-woven material several times, put it in a blast oven, and dry it at 40 ° C, then you can produce into montmorillonite-polyimide composites.

Example 5

Sodium montmorillonite (CEC is 90mmol/100g or 110mmol/100g sodium montmorillonite) and ethanol: water (volume percentage 50%: 50%) is configured into 200g of a dispersion liquid of 4% by weight, and then use The cell pulverizer was processed at 600-800W for 3200s to disperse the dispersion evenly. Adjust the pH value of the dispersion to 12 with 1M NaOH aqueous solution. Pour the dispersion into a shallow flat-bottomed container. Put it into a blast oven and dry it at 60°C to make a translucent flexible inorganic montmorillonite film. If the dispersion liquid is divided into several times and dropped onto the surface of the flat polyimide non-woven material, if the weight gain rate of the material is greater than 60%, then the montmorillonite-polyimide with excellent fire-resistant and heat-insulating properties can be obtained. imine composites.

Claims (7)

1. A preparation method of inorganic montmorillonite material, comprising: (1) Preparation of sodium montmorillonite Mix 2-5g of reagent grade pure montmorillonite, 0.2-2.2g of NaCl and 80-150ml of distilled water. The quality of NaCl is 2-6 times the cation exchange capacity of montmorillonite (CEC), react at room temperature -100°C for 2-12h, cool , centrifuged and washed until there is no Cl ^- in the supernatant; (2) Preparation of inorganic montmorillonite film and montmorillonite-polyimide composite The above-mentioned sodium montmorillonite is mixed with ethanol and water mixture to prepare a dispersion liquid with a weight percentage of 0.5-4%, and the dispersion is uniform, and then the pH of the dispersion liquid is adjusted to 8-13 with NaOH aqueous solution, and dried to obtain an inorganic Montmorillonite film; or add the dispersion liquid on the polyimide non-woven fabric and dry to prepare the montmorillonite-polyimide composite material. 2. the preparation method of a kind of inorganic montmorillonite material according to claim 1 is characterized in that: the reagent grade pure montmorillonite in the described step (1) is replaced with sodium montmorillonite and then directly carries out step ( 2), the CEC of sodium montmorillonite is 90mmol/100g, 110mmol/100g or 113mmol/100g, the purity is >90%, and the particle size is 2.0-10μm. 3. the preparation method of a kind of inorganic montmorillonite material according to claim 1 is characterized in that: the volume percentage of ethanol and water in the ethanol and water mixed solution in the described step (2) is 25%～50% : 50-75%. 4. the preparation method of a kind of inorganic montmorillonite material according to claim 1, is characterized in that: the NaOH aqueous solution concentration in the described step (2) is 1M. 5. the preparation method of a kind of inorganic montmorillonite material according to claim 1, is characterized in that: the uniform concrete process of dispersing in described step (2) is to adopt ultrasonic cell pulverizer to process montmorillonite dispersion liquid 600- 3200s, the power is 600-800W. 6. The preparation method of an inorganic montmorillonite material according to claim 1, characterized in that: the drying temperature in the step (2) is room temperature-60°C. 7. the preparation method of a kind of inorganic montmorillonite material according to claim 1, is characterized in that: the weight percent of montmorillonite in the montmorillonite-polyimide composite material in described step (2) 20 %-140%, the thickness of polyimide non-woven material is 2-3mm.

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