KR100925355B1 - Preparation of nano pore control type Alc panel - Google Patents

Abstract

According to the present invention, (a) slaked lime, silica sand, cement and gypsum are mixed with a base component having a CaO / SiO 2 ratio of 0.5-1.0 by the slaked lime and silica sand, (b) a porous inorganic material and (c) a binder Thereby, there is provided a method for forming a nano-pore controlled humidity control foamed light weight concrete panel by press-molding a predetermined shape panel and performing hydrothermal synthesis reaction at a temperature of 100 ° C. to 200 ° C.

Lightweight Foamed Concrete, Tobe Morite, Hydrothermal Synthesis

Description

Manufacturing method of light weight concrete panel with nano-pore control humidity control function {Preparation of nano pore control type Alc panel}

1 is a CaO-SiO2-H2O compositional diagram for explaining various forms of tbemorite crystals.

Figure 2 is a model showing the tobemorite crystal structure.

3 is an explanatory diagram showing the diffusion and adsorption action of water in the panel of the present invention.

Figure 4 is a graph showing the results of the moisture-absorbing moisture absorption characteristics of the panel according to the type and content of the foaming agent according to an embodiment of the present invention, Figure 4a is diatomaceous earth, Figure 4b is ocher, Figure 4c is used as a porous inorganic material metakaolin Graph showing the moisture absorption and moisture resistance test results of the panel.

5 is a scanning electron micrograph of the surface and interior of the conventional panel and the surface and the interior of the control panel.

Figure 6 is a scanning electron micrograph of the surface and the inside and the surface of the inside and the diatomaceous earth 30% mixed panel of the diatomaceous earth 10% mixed according to the present invention.

The present invention relates to the manufacture of lightweight foamed concrete (ALC) panels, and more particularly, to a method for manufacturing nanoporous controlled humidity-absorbing lightweight foamed concrete panels using dry molding and hydrothermal synthesis.

Recently, the use of organic materials as building materials is regulated due to human health hazards and fire hazards caused by volatile organic compounds (VOC), and the use of inorganic materials is gradually increasing, and inorganic materials are not only functions of interior materials. It is controlled to express the beneficial functionality to the human body. Such changes in building interior materials have greatly increased the level of consumer's demand due to the widespread public health of organic interior materials caused by broadcasting and other media reports, and accordingly, the functionality of inorganic interior materials has been gradually developed to meet the demand level. to be.

Recently, Japan produces and sells humidity control function (humidity function, breathing material, known as breathing material) and insulation type expression panel by controlling porous inorganic material, which is mentioned as one of the representative technologies of inorganic panel.

In order to develop a product that can satisfy the above characteristics, it is essential to develop a panel manufacturing technology capable of controlling nanopores and manufacturing a porous panel. In particular, humidity tiles fired at existing high temperatures are imported and depend on imports. Therefore, it is essential to develop a low energy consumption low temperature panel.

When developing hybrid composite functional nano-pore control ceramic panel for building interior which can control pore and moisture, it is possible to produce high functional products that can provide insulation and condensation reduction function. As a result, it is possible to manufacture high value-added panels that can solve the economic and quality problems of existing ALC, gypsum board, and other interior and exterior wall finishing materials. In particular, it is possible to replace high-temperature products imported from Japan with low-temperature products. If technology development is established, it will be possible to export as well as import substitution effect.

Accordingly, an object of the present invention is to provide a hybrid composite functional nano-pore control ceramic panel for building interiors, which can be manufactured with low energy, and capable of controlling pores and moisture.

According to the present invention, (a) containing slaked lime, silica sand, cement and gypsum, the base component of which the CaO / SiO 2 ratio is adjusted to 0.5-1.0 with slaked lime and silica, and (b) diatomaceous earth, metakaolin, ocher and volcanic stone. The porous material selected from the group and (c) the binder is kneaded and press-molded into a panel having a predetermined shape and subjected to hydrothermal synthesis reaction at a temperature of 100 ° C. to 200 ° C. Provided is a method for preparing.

Hereinafter, the present invention will be described in more detail.

The hydrothermal synthesis method according to the present invention enables the production of panels of desired properties with low energy. The hydrothermal synthesis method used in this invention mixes the raw material which has CaO as a main component, and the raw material which has SiO2 as a main component with mixed water, and then performs a hydrothermal synthesis reaction on temperature conditions of 100 degreeC-200 degreeC.

Taylor et al. Described the process by which tobemorite crystals were produced under the above temperature conditions:

1) When the CaO / SiO2 molar ratio is 0.8 or less, CSH (I) is produced by the reaction of CSH (II), which is an initial product of reaction, and SiO2, and CSH (I) is changed to tobemorite as the reaction proceeds. This reaction rate depends on the temperature and, if the reaction temperature is high enough, it may change to Zonotlite.

2) When the molar ratio of CaO / SiO2 is between 0.8 and 1.0, CSH (II) and CSH (I) are formed at the beginning of the reaction, and CaO is lost before SiO2.

The base component used in the present invention contains quicklime, silica sand, cement, and gypsum, and the tbemorite hydrate is produced by hydrothermal synthesis by adjusting the CaO / SiO 2 ratio to 0.5-1.0.

In addition, the porous material used in the present invention is used to control the appropriate nano-pores, one or two or more mixtures selected from the group consisting of diatomaceous earth, metakaolin, ocher and volcanic stone, the amount of the base component It is 30 weight part or less with respect to 100 weight part, More preferably, it is 1-30 weight part.

In the present invention, a binder is used to dry form the base component and the porous material by mixing. Preferred binders for use include polyvinyl alcohol (PVA), water glass and the like.

The chemical composition of the base component and the porous inorganic material used in the present invention is shown in Table 1.

According to the present invention, the base component, the porous material and the binder are mixed and press-molded into a panel of a predetermined shape. For example, for press molding, after the above-mentioned mixture is filled in a press molding mold, a method of pressurizing at a pressure of 50 to 200 kgf / cm 2 for 0.5 to 2 minutes may be used. As such, after pressing and hydrothermal synthesis, various types of tobemorite crystals may be generated as shown in FIG. 1.

The tobemorite crystal is a continuous structure of SiO 4 tetrahedron in a Ca (OH) 2 layer as shown in FIG. 5, in which Ca 2+ ions or H 2 O are located in the cavity between the silicate ion layers. At this time, the thickness of the interlayer of the cavity is called, for example, tobemorite of 1.1 nm or 1.4 nm. This cavity can act as nano-sized micropores, contributing to the absorption and release of moisture.

In particular, when using a porous inorganic material of diatomaceous earth, metakaolin, ocher, volcanic stone, etc., it is possible to obtain a control effect of nano pores (nano pore).

By using the substrate and the porous material according to the present invention, it is possible to appropriately control the nanopores, and then to form nanopores once again by the formation of tobemorite, thereby controlling the formation of the pores.

The nano-pore controlled moisture-absorbing lightweight foam concrete panel manufactured by the present invention is capable of controlling the movement of moisture by hydrogen bonding with the panel material as shown in FIG. 3.

The effects and other features of the present invention as described above will become more apparent from the following examples.

EXAMPLE

Sintered lime, silica, cement and gypsum were used as the base components, PVA or water glass was used as the binder, and diatomaceous earth was used as the porous material.

Calcined lime, silica sand, cement and gypsum were mixed, but the CaO / SiO2 ratio was adjusted to 0.5-1.0 with quicklime and silica sand, and porous materials of diatomaceous earth, loess and metakaolin were mixed in an amount of 1 to 30% by weight.

After mixing the non-porous material (control example: Ref.) And the sample mixed with 10%, 20%, and 30% porous material (ex.) With the binder (W / P = 0.15) Filled in a press molding mold and pressurized using a pressurizer at a pressure of 50-200 kg / f for 0.5-2 minutes. After demolding the specimen, hydrothermal synthesis in an autoclave (maintained at 180 ° C. for 7 hours), followed by slow cooling and removal of the specimen from the autoclave when reaching room temperature, and sufficient drying after reaching a constant condition at 100 ° C. Hygroscopic properties were tested. The hygroscopic properties were prepared by measuring the size of the test piece at 200 × 200 × 7 mm, and then maintaining the weight under a condition of 23 ° C.-40% relative humidity until weighing was measured (w1).

Thereafter, the relative humidity was changed to 23 ° C.-70% and maintained for 12 hours to measure the weight (w2). At this time, the moisture absorption amount was calculated as the change amount of water per unit area [(w2-w1) /0.04 m 2].

The panels prepared by mixing the porous mixtures were placed in a thermo-hygrostat and the humidity was changed to evaluate the hygroscopic properties. The moisture absorption time was fixed to 12 hours, after which the moisture absorption amount was measured by measuring the weight before and after moisture absorption, which is shown in FIG. 4.

As can be seen in Figure 4, the moisture absorption of the control sample was about 80g / ㎡ level, the moisture absorption was very high in the specimen mixed with diatomaceous earth, especially the moisture absorption amount of 280g / ㎡ in 30% diatomaceous earth very good results Was derived. This is due to the porous properties of the starting material and the low specific gravity (high porosity) of the prepared specimens, it is considered that the moisture absorption characteristics are greatly improved. In addition, the metakaolin 10% mixed sample showed better moisture absorption characteristics than the control example.

Moisture-proof properties were also excellent in the diatomaceous earth mixed specimens, which is two times better than the control sample. In other words, when the panel was manufactured by mixing diatomaceous earth and metakaolin together with quicklime, silica sand, cement, and gypsum, it was confirmed that a panel having excellent moisture absorption and moisture absorption characteristics was manufactured.

5-6 is a conventional panel (Sarara of Japan), a control example. The microstructure of the panel with 10% and 30% of diatomaceous earth added was taken by scanning electron microscope. As shown in the photograph, it was confirmed that the tobemorite crystals were produced in both the control sample and the diatomaceous earth mixed specimen, and it was also found that some of the silica sand particles which had not been terminated yet existed. In particular, it was observed that the tobemorite crystals were composed of empty spaces having a size of 50-500 nm. This is thought to be able to sufficiently affect the absorption of moisture.

As described above, when the porous material and the binder are mixed with the base component according to the present invention, pressurized and dry hydrothermally synthesized, the nano-pore controlled humidity control function lightweight foam concrete panel exhibits excellent humidity control (moisture absorption) characteristics. It becomes possible to manufacture with.

Claims (5)

(a) a base material containing calcined lime, silica sand, cement and gypsum, the CaO / SiO 2 ratio being adjusted to 0.5-1.0 with calcined lime and silica sand, and (b) a porous inorganic material and (c) a binder. A method for producing a nano-pore controlled humidity-modifying lightweight concrete panel, which is press-molded with a panel and subjected to hydrothermal synthesis at a temperature of 100 ° C to 200 ° C. The method according to claim 1, wherein the porous inorganic material is one or a mixture of two or more selected from the group consisting of diatomaceous earth, metakaolin, ocher and volcanic stone. The method of claim 1, wherein the porous inorganic material is used in an amount of 1 to 30 parts by weight based on 100 parts by weight of the base component. The method according to claim 1, wherein polyvinyl alcohol or water glass is used as the binder. Nanopore controlled humidity control function lightweight foam concrete panel manufactured by the method of any one of claims 1 to 4.

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