KR20050078506A - Asbestos-free insulation board and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a non-asbestos heat insulating plate and a method of manufacturing the same. The non-asbestos insulation plate of the present invention is composed of 5 to 40% by weight of the filler, 30 to 80% by weight of the binder, 5 to 50% by weight of the reinforcing material, the reinforcing material includes one selected from organic fibers consisting of aromatic polyaramid, ceramics, Characterized in that it is a mixed form containing at least one inorganic fiber selected from the group consisting of glass fiber, rock wool, haemulseok and talc, the part of adding 5 parts by weight of water to the dry blending method, 100 parts by weight of the blended raw materials Blending in at least one method selected from the group consisting of a dry blending method and a wet blending method in which 100 parts by weight of water is added to 100 parts by weight of raw materials; Preparing a mixture by adding 60 to 80 wt% of water to the blended raw material and mixing at 500 to 2000 rpm for 2 to 10 minutes; Pressing the mixture to 180 to 250 kg · f / cm ² to form a plate; Curing the molded plate; And it can be prepared by the step of polishing the cured plate.

Description

Non-asbestos insulation board and its manufacturing method {ASBESTOS-FREE INSULATION BOARD AND MANUFACTURING METHOD THEREOF}

The present invention relates to a non-asbestos heat insulating plate and a method of manufacturing the same, and more particularly, to a heat resistant heat insulating plate and a method of manufacturing the same by removing asbestos from the material of the high-grade heat resistant heat insulating plate.

Insulation is commonly used to prevent heat losses caused by conduction heat transfer or to minimize energy losses. Insulation materials are generally known to be made from fillers that cure in the atmosphere or under vapor pressure, binders containing calcium silicate and reinforcing fiber materials. In the preparation, the components of the binder, namely calcium silicate or hydrated lime, must react with silica and water to form known calcium silicate hydrate structures. The structure of the coagulation binder will depend on the relative proportions of hydrated lime and silicon that can actually react under the reaction conditions. In this case, the properties of the product depend on the reinforcing fiber material added, and asbestos is useful for this purpose. Therefore, heat insulating plates manufactured using asbestos have been spotlighted in this field for their high heat resistance and light weight.

However, the asbestos is mainly obtained from a natural stone called serpentine, which has a frost-like shape and has a long and fibrous crystal growth, and inhalation of such fibrous asbestos dust causes lung cancer or mesothelial tumor. It has been reported by experiment. Therefore, as a result of the harmfulness of asbestos, asbestos is heavily regulated at home and abroad, alternative products for asbestos are being developed one after another.

The trend in the release of non-asbestos products suggests that asbestos is replaced with cellulose fibers and / or organic fibers and / or alkali-resistant glass fibers to produce lightweight insulating plates. However, these products have not yet achieved satisfactory results under toxic test conditions according to DIN 53436 as well as their mechanical properties or flame retardancy are lower than those with asbestos. In addition, these non-asbestos products point out the disadvantages of products containing asbestos, rather limit the usefulness of non-asbestos products.

On the other hand, British Patent No. 1,498,966 discloses the manufacture of flame retardant insulation plates using mica as a filler, and the invention further provides light fillers, expanded perlite or puffed clay as needed. And hydraulic calcium silicate binders, portland cement, alumina cement, blast furnace slag cements as binders.

In addition, Korean Patent Publication No. 1995-9494 proposes a lightweight insulating plate using portland cement, fibers and fillers, in addition to about 8 to 25% by weight of hydrated lime, preferably about 10 to 18% by weight, as a binder. have.

In order to prepare asbestos-free, flame-retardant light-insulating plates, a binder prepared from a product cured in an autoclave has been known to have excellent thermal stability and mechanical load. However, the present invention uses a binder which solidifies at room temperature. . Therefore, since it does not cure in the autoclave, it can prevent energy consumption and solve the problem of cost increase, and it is possible to overcome the problem that the crystalline silicon dioxide liberated under the high temperature and high pressure state remains unreacted and impairs the health of the worker. I'm proposing.

In addition, an example of a heat insulating plate having high mechanical strength without using asbestos is a structure in which heat-resistant synthetic paper sheets formed of aromatic polyamides or polyimides are integrally bonded to each other and stacked into a plurality of sheets, and inside the plurality of synthetic paper sheets. Insulation plates in which two or more metal films are inserted are known (Korean Patent Publication No. 185714).

The heat insulating plate has excellent heat dissipation, fabric properties, dimensional stability, and is known to be excellent in resistance to various compounds and industrial solvents. There is a characteristic that does not deteriorate. In addition, since the rigidity and elongation is large, the fabricability is excellent, it can be processed by the existing fabric device.

In addition to the polyamide resin, research on the development of new fibers with improved properties has been continuously conducted. As a result, aromatic polyaramid fibers made from the polymer compound polyaramid are representative. Polyaramid fibers are used in bulletproof vests, fire suits, heat resistant clothing, rope materials, ropes or belts because they are lightweight, resilient and heat resistant, and have a high strength comparable to those of alloys of titanium and iron used in ballistic vests. have. However, an example of producing a heat insulating plate using the characteristics of such aromatic polyaramid fibers has not been reported so far.

Accordingly, the present inventors have tried to obtain a heat insulating plate having high mechanical strength without containing asbestos, and as a result, 5 to 40% by weight of the filler, 30 to 80% by weight of the binder, and 5 to 50% by weight of the reinforcement, in particular, the reinforcement The present invention was completed by confirming that a desired heat insulating plate can be obtained from a mixed composition characterized by containing one organic fiber made of an aromatic polyaramid fiber.

It is an object of the present invention to provide a non-asbestos insulation plate consisting of 5 to 40% by weight of filler, 30 to 80% by weight of binder, and 5 to 50% by weight of reinforcement.

Another object of the present invention is a dry blending method, 5 to 40% by weight of the filler, 30 to 80% by weight of the binder, 5 to 50% by weight of the reinforcing material, partial dry blending method and the raw material 100 to add 5 parts by weight of water to 100 parts by weight of the blended raw material Blending by at least one method selected from the group consisting of a wet blending method adding 100 parts by weight of water to parts by weight; Preparing a mixture by adding 60 to 80 wt% of water to the blended raw material and mixing at 500 to 2000 rpm for 2 to 10 minutes; Pressing the mixture to 180 to 250 kg · f / cm ² to form a plate; Curing the molded plate; And it provides a manufacturing method consisting of the step of polishing the cured plate.

In order to achieve the above object, the present invention is a heat insulating plate made of a filler, a binder, and a reinforcing material, 5 to 40% by weight of the filler, 30 to 80% by weight of the binder, 5 to 50% by weight of the reinforcing material To provide.

More specifically, the reinforcing material provides an insulating plate, characterized in that it comprises at least one organic fiber made of aromatic polyaramid and / or at least one inorganic fiber selected from the group consisting of ceramic, glass fiber, rock wool, haemulseok and talc. .

Filler is 5 to 40% by weight of at least one selected from the group consisting of mica, wollastonite, perlite and talc, more preferably 5 to 15% by weight. At this time, when the amount of the filler used is 5% by weight or less, there are disadvantages in that the porosity increases and the strength becomes weak, and when the amount of the filler is 40% by weight or more, the pore is too small and the heat insulation effect is not preferable.

In particular, when mica is used as the filler, it is possible to use commercial grades, but it is more preferable when at least 60% of the particles have a size smaller than 250 µm. The proportion of particles having a size larger than 500 μm should be less than 3%. Otherwise, the strength may be weakened due to insufficient binding force in the manufacturing process.

When the wollastonite is used as a filler as a calcium silicate component obtained by reacting silica and water, it is preferable to use the wollastonite within a range of 5 to 15 wt% because the mechanical properties thereof are lowered when the amount thereof is 15 wt% or more.

In addition, when using the perlite as a filler, it is preferable to use within 5 to 10 range because it is excellent in thermal insulation and is advantageous for high temperature use of about 1000 ℃, but the volume is large so that the specific gravity of the product can be reduced.

The binder may be selected from cement or clay components, and other materials having excellent heat resistance may be used in addition to the above components. At this time, the binder is preferably used 30 to 80% by weight, but less than 30% by weight may be weakened by the lack of bonding strength, when more than 80% by weight may be relatively weak in impact due to the insufficient reinforcement. .

The reinforcing material of the present invention is characterized by being mixed with an organic fiber composed of aromatic polyaramid alone or an inorganic fiber selected from the group consisting of the organic fiber and a conventional ceramic, glass fiber, rock wool and haemulseok. That is, the reinforcing material may be used in a mixed form including at least one inorganic fiber selected from the group consisting of organic fiber made of aromatic polyaramid and ceramic, glass fiber, rock wool and haemulseok, and the total amount of reinforcing material is 5 To 50% by weight is preferred. In particular, it is preferable to use 1 to 3% by weight of the organic fiber composed of aromatic polyaramid, and if less than 1% by weight, the flexural strength of the function as a reinforcement for asbestos replacement is weak, and if it exceeds 3% by weight, the expensive aromatic It is uneconomical due to the excessive use of polyaramid. As the aromatic polyaramid component used in the present invention, synthetic or commercialized materials may be used.

The present invention provides a method for producing a heat insulating plate using a mixed composition containing 5 to 40% by weight of filler, 30 to 80% by weight of binder, and 5 to 50% by weight of reinforcing material. More preferably, at least one organic fiber composed of 5 to 40% by weight of a filler, 30 to 80% by weight of a binder, an aromatic polyaramid, and an inorganic fiber selected from the group consisting of ceramic, glass fiber, rock wool, calcite and talc. It provides a method for producing a heat insulating plate using a mixed composition containing 5 to 50% by weight of reinforcement.

More specifically, the manufacturing method of the present invention

Blending 5 to 40 wt% of the filler of the present invention, 30 to 80 wt% of the binder, and 5 to 50 wt% of the reinforcing material;

Preparing a mixture by adding 60 to 80 wt% of water to the blended raw material and mixing at 500 to 2000 rpm for 2 to 10 minutes;

Pressing the mixture to 180 to 250 kg · f / cm ² to form a plate;

Curing the molded plate; And

And grinding the cured plate.

The compounding step may be any effective means for progressing the raw material to the reaction without loss, but dry blending method of the raw material, partial dry blending method of adding 5 parts by weight of water to 100 parts by weight of the blended raw material and water by 100 parts by weight of the raw material It may be performed by at least one method selected from the group consisting of a wet compounding method to add 100 parts by weight. Among these, the partial dry blending method of adding 5 parts by weight of water to 100 parts by weight of the blended raw material prevents the generation of static electricity generated when the raw materials are blended, and residues remain in the mixer to lower the yield and separate process for removing them. It is more preferable because this becomes unnecessary.

The curing step may be performed alone or continuously in a curing step or a natural curing step for 15 to 48 hours in the air in a dryer maintained at 30 to 60 ℃ for 24 to 48 hours, minimizing the residual amount of water on the cured plate In order to improve the quality of the final product, continuous performance is more preferable.

The cured plate is smoothly polished to fit the surface is molded to a thickness of 5 to 100 mm depending on the application.

Hereinafter, the present invention will be described in more detail with reference to Examples.

This embodiment is intended to illustrate the present invention in more detail, and the scope of the present invention is not limited to these examples.

<Example 1>

3% by weight of aromatic polyaramid fibers, 5% by weight of inorganic fiber ceramics, 12% by weight of inorganic fiber disintegrated stones, 10% by weight of filler wollastonite, and 70% by weight of inorganic binder were weighed and dry mixed at 6000 rpm for 5 minutes. Then water was added 70% by weight of the composition and mixed for 3 minutes at 1080 rpm. After weighing according to 38 kg and 20 mm thickness, a plate (20 mm thickness) was produced by press molding at a pressure of 200 kgf / cm ² for 10 minutes with a press. The compacted plate was cured for 24 hours in a drier maintained at a temperature of 40 ° C. and a humidity of 80%. After curing in the dryer, it was naturally cured for 18 hours in the atmosphere. Thereafter, the cured plate of 20 mm thickness was polished and processed according to the purpose of use, thereby preparing a non-asbestos insulating plate.

<Example 2>

3% by weight of aromatic polyaramid fiber, 17% by weight of inorganic fiber rock wool, 10% by weight of filler perlite, and 70% by weight of inorganic binder were weighed and dry mixed at 6000 rpm for 5 minutes, and at the same time, water was added to the composition to prevent static electricity. A non-asbestos insulating plate (20 mm thick) was prepared in the same manner as in Example 1, except that 5 wt% of the mixture was added.

<Example 3>

Weigh 3% by weight of aromatic polyaramid fiber, 17% by weight of inorganic fiber disintegrated stone, 10% by weight of filler mica, and 70% by weight of inorganic binder, and dry mix at 3600 rpm for 10 minutes while simultaneously adding water to 100% by weight of the composition. Except for blending, it was carried out in the same manner as in Example 1 to prepare a non-asbestos insulating plate (20 mm thickness).

Comparative Example 1

5 wt% of inorganic fiber ceramics, 12 wt% of inorganic fiber disintegrated stone, 10 wt% of filler wollastonite, and 70 wt% of inorganic binder were mixed and mixed at 6000 rpm, except that organic fibers were not used. The same procedure was followed to prepare a heat insulating plate (20 mm thick).

Experimental Example 1

About the insulation boards manufactured in Examples 1 to 3 to Comparative Example 1, flexural strength and impact resistance were measured and listed in Table 1.

1. Measurement of flexural strength

A test piece was prepared by cutting the heat insulating plate prepared in Examples 1 to 3 to Comparative Example 1 to 10 mm × 10 mm, and was placed horizontally on two points separated by 100 mm, and gradually loaded under both points to cut the load. Was measured. At this time, the flexural strength was calculated by Equation 1 below.

(In the above, P : force {kgf (N)}, L : distance between points (100 mm), b : width of the test piece (10-20 mm), and h : thickness of the test piece (mm).)

2. Impact strength measurement

After preparing the test piece of the insulating plate prepared in Examples 1 to 3 to Comparative Example 1 by cutting to 10 mm × 10 mm, using a Charpy impact tester (capacity about 30 kgf · cm) {N · cm} between the points The distance is set to 60 mm, and the prepared test piece is placed at both points, and the minimum kgf · cm {N · cm} cut by hammering the center part once with a hammer is divided by the circular cross-sectional area (cm ² ) at the incision. Determined. Plates less than 8 mm thick are not tested.

Mechanical Properties of Insulation Plates division Mechanical properties Flexural strength (room temperature), MPa Flexural Strength (After Heating), MPa Impact resistance, kJ / m ² Example 1 14.0 9.2 2.4 Example 2 13.8 12.2 1.8 Example 3 11.4 9.4 1.8 Comparative Example 1 10.5 10.4 1.3

As shown in Table 1, the non-asbestos heat insulating plates prepared in Examples 1 to 3 were superior to Comparative Example 1, which is a non-asbestos heat insulating plate which does not contain glass fibers, and has a flexural strength at room temperature. The impact resistance of the insulation board was confirmed to be 2.0 kJ / m ² , which is usually superior to the non-asbestos insulation board. Therefore, the heat insulating plate of the present invention showed non-asbestos and mechanical properties comparable to those of asbestos products.

As described above, the present invention provides a non-asbestos heat insulating plate of the present invention by first providing a non-asbestos heat insulating plate having excellent mechanical properties such as flexural strength, impact strength, impact resistance and the like, without including asbestos. It can be used for heat press, furnace, or high frequency as heat insulation for machinery,

Second, the filler, binder and reinforcing material composition of the present invention is prepared by mixing in a single reaction tank ( in situ ) without a separate pretreatment, there is an effect that the process is simplified.

Although the present invention has been described in detail only with respect to the described embodiments, it will be apparent to those skilled in the art that various modifications and variations are possible within the technical scope of the present invention, and such modifications and modifications are within the scope of the appended claims.

Claims (6)

Insulation material consisting of a filler, a binder and a reinforcing material, 5 to 40% by weight of the filler, 30 to 80% by weight of the binder, 5 to 50% by weight of the reinforcing material, the reinforcing material is an organic fiber alone or the organic material consisting of aromatic polyaramid A non-asbestos insulation board comprising a fiber and a mixed form containing at least one inorganic fiber selected from the group consisting of ceramic, glass fiber, rock wool, haemulseok and talc. The non-asbestos heat insulating plate according to claim 1, wherein 1 to 3 wt% of organic fibers composed of the aromatic polyaramid are included. 5 to 40% by weight of the filler of claim 1, 30 to 80% by weight of the binder, 5 to 50% by weight of the reinforcing material; Preparing a mixture by adding 60 to 80 wt% of water to the blended raw material and mixing at 500 to 2000 rpm for 2 to 10 minutes; Pressing the mixture to 180 to 250 kg · f / cm ² to form a plate; Curing the molded plate; And Method for producing a non-asbestos heat insulating plate, characterized in that consisting of the step of polishing the cured plate. The method of claim 3, wherein the blending step is selected from the group consisting of a dry blending method, a partial dry blending method for adding 5 parts by weight of water to 100 parts by weight of the blended raw material, and a wet blending method for adding 100 parts by weight of water to 100 parts by weight of the raw material. Method for producing the non-asbestos insulation plate, characterized in that carried out by at least one method. The method according to claim 3, wherein the curing step is carried out alone or continuously selected in the curing step in the dryer maintained at 30 to 60 ℃ for 24 to 48 hours or in the natural curing step for 15 to 48 hours in the atmosphere, Method for producing a non-asbestos insulation board. According to claim 3, wherein the reinforcing material is an organic fiber consisting of aromatic polyaramid alone or a mixture containing one or more of the organic fibers and at least one inorganic fiber selected from the group consisting of ceramic, glass fiber, rock wool, haemulseok and talc. The method of manufacturing the non-asbestos heat insulating plate, characterized in that the form.