KR100284707B1 - Cement board composition for the extrusion molding and method of preparing the same - Google Patents

Abstract

The present invention relates to a cement-based board composition for extrusion molding and a manufacturing method thereof, more specifically, 40 to 70% by weight of cement powder, 10 to 30% by weight siliceous raw material, 0.2 to 3% by weight of methyl cellulose thickener, The present invention relates to an extruded cement-based board composition comprising 5 to 10% by weight of paper sludge, 1 to 5% by weight of pigment, and 10 to 30% by weight of mixed water, and a method of manufacturing a cement board by extrusion molding the same. The composition according to the present invention is suitable for molding complex and various shapes such as hollow parts, irregularities and the like, and can be freely manufactured in the length of the product because it is not bound by a constant mold.

Description

Cement board composition for the extrusion molding and method of preparing the same

The present invention relates to a cement-based board composition for extrusion molding and a method for manufacturing the same, and more specifically, to apply to interior materials, exterior materials, etc. in building materials, cement-based materials such as portland cement, slag cement, thickeners, siliceous raw materials, fiber reinforcement materials. (Paper Sludge), etc. The present invention relates to a cement-based board composition for extrusion molding and a method for producing the cement-based board which can be produced by an extrusion molding method.

In general, cement-based boards used for interior or exterior materials of buildings are composed of cement and fiber, so that the fire, fire, and sound insulation are excellent, so that the walls of insulation houses, heating panels, partitions of apartments or townhouses, highways or train sections It can be applied to sanitary structures such as soundproof walls, barns and pig yarns, and pollution-free homogeneous structures.

Looking at the prior art known in the prior art, the Republic of Korea Patent Publication No. 96-29542 discloses that the starting material is a fiber reinforcing material (paper sludge) 50 to 60%, cement 25 to 30%, resin powder 15 to 20% ratio The sludge fed into the injection machine by mixing and conveying is controlled by the injection port, and the thickness and the width are controlled. The sludge is preformed by the temperature of 60 ~ 70 ℃ of the injection port, and is gradually compressed by the belt press. A pre-formed product cut by an automatic cutting machine during transfer of a mold is put into a mold of a press, molded by a temperature of 150-200 ° C. of a mold and a press of a press, and a compressed board manufactured by spraying a water-resistant solution on a surface thereof and drying it is disclosed. .

In Korean Patent Laid-Open Publication No. 96-41115, paper sludge and water are mixed with cement, and a small amount of calcium chloride is added to the mixture to accelerate curing and increase strength, thereby obtaining a slurry, and press forming the slurry to obtain a board. Disclosed is a method for producing a cement board to be cured.

In addition, Korean Patent Laid-Open Publication No. 96-22353 prepares a cement slurry by mixing paper sludge and water in cement, mixes the diluted blowing agent while adding compressed air at about 10 atm, and stirs strongly at high speed. Then, a method for producing a lightweight foamed sound-absorbing and dustproof plate which is coated and cured to a certain thickness on a composite panel is disclosed.

However, the compression board manufactured according to the prior art described above is not an extrusion molding method, but is a batch production method in the process, so the efficiency is low in terms of productivity, and there is a difficulty in forming a complicated and various shapes such as hollow parts and irregularities. The length of the product is limited because of the use of the mold. And since the manufacturing process is complicated, economical efficiency and productivity tend to be low.

Therefore, in the present invention, as a result of extensive research to solve the above problems, it was found that the cement slurry having an appropriate adhesive force can be extruded and solved the above problems by compression molding the cement slurry. The invention has been completed based on this.

Accordingly, an object of the present invention is to provide a cement-based board composition capable of extrusion molding.

Another object of the present invention to provide a method for producing a cement-based board by the extrusion molding method using the composition.

The production method of the present invention for achieving the above another object consists of mixing the composition to produce a cement slurry, and then injecting the slurry into an extruder having a vacuum degassing chamber to extrude.

The composition of the present invention for achieving the above object is 40 to 70% by weight of cement powder, 10 to 30% by weight of siliceous raw material, 0.2 to 3% by weight of methylcellulose thickener, 5 to 10% by weight of paper sludge, pigment 1 to 5 weight% and 10-30 weight% of mixed water, and it has the adhesive force of 0.01-0.05 Mpa.

Looking at the present invention in more detail as follows.

According to the present invention, portland cement or slag cement is generally used as a base material, and fine diatomaceous earth, perlite and / or vermiculite are used as a siliceous raw material. In addition, methyl cellulose-based thickener was used to impart proper adhesive strength and plasticity, and paper sludge and wood chips, which are currently produced in the paper industry, are used as fiber reinforcement materials. Pigments were added as appropriate.

In addition, extrusion was used for the extrusion machine which has a twin screw and a vacuum degassing chamber. In addition, the shape of the outlet has the advantage that a variety of products can be obtained because it can be freely deformed by changing the mold.

Cement board composition according to the present invention is 40 to 70% by weight cement powder, 10 to 30% by weight siliceous raw material, 0.2 to 3% by weight methylcellulose thickener, 5 to 10% by weight papermaking sludge, 1 to 5% by weight pigment And 10 to 30% by weight of mixed water.

The cement powder is usually portland cement or slag cement, which is shipped from a domestic cement company, and the cement of the cement is a powder of about 2,500 to 4,500 cm ² / g. The amount is preferably 40 to 70% by weight, but if it is less than 40% by weight, the extrudate tends to crack at the outlet, and when it exceeds 70% by weight, the shape retention tends to be inferior.

The siliceous raw material of the present invention can compensate for the dry shrinkage, which is a characteristic of cement itself, and can be lightened while lowering the density of the extrudate. The siliceous raw material used was one or more components selected from the group consisting of diatomaceous earth, perlite and vermiculite, it is preferable that the average particle size is 65 to 100 mesh to control the adhesion of the final cement slurry.

In addition, the amount used was 10 to 30% by weight. If less than 10% by weight, cracking occurs over time, and if it exceeds 30% by weight, the surface of the extrudate tends to be rough.

On the other hand, in order to impart moldability to the extruded product, a powdery methylcellulose thickener was used in an amount of 0.2 to 3% by weight. If the amount of the thickener is too large, the slurry adheres to the inside of the extruder so that extrusion is not performed without countercurrent. If too small, the viscosity is insufficient to cause the material to split at the exit.

Paper sludge, which is used as industrial waste in paper companies, is preferably used as much as possible in terms of waste resource utilization, but in the present invention, it is used in an amount of 5 to 10% by weight, which means that if the amount of paper sludge is too large, curing of the cement slurry is required. It is because there exists a tendency which the floating phenomenon which a surface produces in the middle arises.

In addition, yellow pigments, red pigments, green pigments or blue pigments made of an inorganic material may be used so as to be suitable for use as a color board, and the amount thereof is preferably 1 to 5% by weight in terms of economy.

If the mixed water is added too much, it will not be extruded, and if too little, the cement slurry will be quenched in the extruder. Due to such characteristics, 10 to 30% by weight is preferable.

The adhesive force of the composition of the present invention having such a composition is only in the range of 0.01 to 0.05 MPa to enable extrusion. If the viscosity is less than 0.01 MPa, the shape retention of the slurry deteriorates, and if it exceeds 0.05 MPa, the activity tends to deteriorate.

Meanwhile, according to the present invention, extrusion was performed in a molding machine with a vacuum degassing chamber, and the raw material slurry was introduced into a raw material inlet, and large pores existing in the material in the vacuum degassing chamber escaped to the outside to form a dense material. This was deformed to obtain extrudates of various shapes through the outlet.

Steam curing of this extrudate has a pretreatment time of about 2 hours at room temperature (approximately 20 ℃) and relative humidity of 90% or higher, and it is raised to about 80 ℃ at an elevated temperature rate of about 15 ℃ per hour and maintained for about 4 hours. Slow cooling.

The cement-based board manufactured by the extrusion molding method is suitable for molding complex and various shapes such as hollow parts, irregularities, and the like, and is free from manufacturing a length of a product because it is not bound by a predetermined mold. In addition, it is possible to produce products of a relatively different thickness, it is possible to freely manufacture by simply replacing the mold within a certain range (10 ~ 100mm). In addition, productivity can be improved because the production can be carried out continuously.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the scope of the present invention is not limited to the following Examples.

Example 1

The composition was prepared by mixing 55.8% by weight of Portland cement powder, 19.2% by weight of No. 8 silica sand, 6% by weight of papermaking sludge, 2.8% by weight of pigment, 0.4% by weight of thickener and 15.8% by weight of mixed water.

First, 600 g of papermaking sludge having a water content of 60% is well released using a stirrer to 1.58 kg of mixed water. In a three-stage mixer, 5.58 kg of cement, 1.92 kg of No. 8 silica, 280 g of pigment, and 40 g of thickener (Metoluse, Japan) are mixed well. Cut to 40 × 160mm size and used for bending strength test, 10 × 10 × 10mm for density test, permeability test, water absorption and moisture content specimens cut to 10 × 70 × 100mm for length change test At each of the three test items, atmospheric steam was cured. On the other hand, compared with the general cement board (JIS 5414, 5404, etc.) as a comparative example, the results are shown in Table 1 below.

Steam curing of the test specimens had a pretreatment time of 2 hours at 20 ° C. and a relative humidity of 90% or more. The temperature was raised to 80 ° C. at a temperature rising rate of 15 ° C. per hour, and then maintained for 4 hours.

To As can be seen from Table 1, the bending strength can be seen that significantly higher compared to the normal cement board (such as JIS 5414, 5404) as 125㎏f / cm ² or more. Shrinkage due to absorption was 0.17%, showing little shrinkage. The density was found to be 2.51 g / cm ³ . Absorption rate and moisture content were also found to have good characteristics compared with general cement boards.

Example 2

The composition was prepared by mixing 42% by weight of Portland cement powder, 14% by weight of No. 8 silica, 8% by weight of perlite, 5% by weight of papermaking sludge, 2% by weight of pigment, 1% by weight of thickener and 28% by weight of mixed water.

First, 500 g of papermaking sludge having a water content of 60% is well released using a stirrer to 2.8 kg of mixed water. In a three-stage mixer, 4.2 kg of cement, 1.4 kg of 8 silica sand, 800 g of perlite, 200 g of pigment, and 100 g of thickener (Metoluse, Japan) are mixed and prepared. It was cut into a size of 10 × 40 × 160mm and used for bending strength test, and 10 × 10 × 10mm for density test, and permeability test, water absorption and moisture content specimen were 10 × 70 × 70mm and 10 × 70 × 100mm for length change test. It was cut to size and set to three for each test item, followed by atmospheric steam curing. These results are shown in Table 1 below. Steam curing of the test body was the same as in Example 1.

As can be seen in Table 1, the bending strength is 120kgf / cm ² It can be seen that significantly higher than the general cement board (JIS 5414, 5404, etc.). Shrinkage due to absorption was 0.19%, showing little shrinkage. The density was found to be relatively small at 2.34 g / cm ³ . Absorption rate and moisture content were also found to have good characteristics compared with general cement boards.

Example 3

45% by weight of Portland cement powder, 10.5% by weight of No. 8 silica, 6% by weight of perlite, 4% by weight of vermiculite, 6.5% by weight of paper sludge, 1.2% by weight of pigment, 0.8% by weight of thickener and 26% by weight of mixed water Was prepared.

First, 650 g of paper sludge having a water content of 60% is well released in 2.6 kg of mixed water using a stirrer. In a three-stage mixer, 4.5 kg of cement, 1.05 kg of No. 8 silica, 600 g of perlite, 400 g of vermiculite, 120 g of pigment, and 80 g of thickener (Metoluse, Japan) are mixed well. It was cut out to the board and cut into 10 × 40 × 160mm size and used for bending strength test.10 × 10 × 10mm for density test, permeability test, water absorption and moisture content specimens were 10 × 70 × 70mm and 10 × 70 for length change test. It was cut into a size of 100mm and three pieces for each test item were subjected to atmospheric steam curing. These results are shown in Table 1 below. Steam curing of the test body was the same as in Example 1.

As can be seen in Table 1, the bending strength is 118kgf / cm ² It can be seen that significantly higher than the general cement board (JIS 5414, 5404, etc.). Shrinkage due to absorption was 0.21%, showing little shrinkage. The density was found to be relatively small at 2.31 g / cm ³ . Absorption rate and moisture content were also found to have good characteristics compared with general cement boards.

division Example 1 Example 2 Example 3 Comparative Example ^{* 6)} Flexural Strength ^{* 1)} (㎏ / ㎠) 125 120 118 35 or more Shrinkage ^{* 2)} (× 10 ^-4 ) 0.17 0.19 0.21 0.25 or less Density ^{* 3)} (ρ, g / cm 3) 2.51 2.34 2.31 - Absorption ^{* 4)} (%) 1.86 2.11 2.23 - Water content ^{* 5)} (%) 5.55 5.74 5.81 8 or less

* 1) measured according to JIS R 5201 method

* 2) Measured according to KSF 2424 method

* 3) Measured by Gas Pycnometer

* 4) Measured according to KSF 3203 method

* 5) Measured according to KSF 3203 method

* 6) Comparative example is the standard of JIS 5414 pulp cement plate

As such, the composition according to the present invention is suitable for molding complex and various shapes such as hollow parts, irregularities and the like, and can be freely manufactured in the length of the product because it is not bound by a constant mold. In addition, it is possible to produce products of a relatively different thickness, it is possible to freely manufacture by replacing the mold within a certain range (10 ~ 100mm). In addition, productivity can be improved because the production can be carried out continuously.

Claims (4)

40 to 70 wt% of cement powder, 10 to 30 wt% of siliceous raw material, 0.2 to 3 wt% of methylcellulose thickener, 5 to 10 wt% of papermaking sludge, 1 to 5 wt% of pigment, and 10 to 30 wt% of mixed water It comprises%, and has an adhesive force of 0.01 to 0.05MPa cement-based board composition for extrusion molding. The cement-based board composition for extrusion molding according to claim 1, wherein the cement powder is usually portland cement or slag cement. According to claim 1, wherein the siliceous raw material is one or more selected from the group consisting of diatomaceous earth, perlite and vermiculite, the cement-based board composition for extrusion molding, characterized in that the average particle size is 65 to 100 mesh. After mixing the composition according to claim 1 to prepare a cement slurry, the extrusion method of the cement-based board, characterized in that the slurry is put into an extruder having a vacuum degassing chamber.