Lightweight fiber reinforced cement material

Abstract

To provide a fiber reinforced cement composition comprising cement, fibers, silica, a filler, expanded perlite, and a polymer.SOLUTION: The fiber reinforced cement composition according to the present invention has low density, high toughness, and high flexural strength without containing a volatile composition. When the composition is molded into a workpiece, the work piece is lightweight, is easily cut and / or made to have a desired shape using a lathe, can be punched, fastened with a screw and / or repeatedly nailed down on the same spot, is resistant to humidity, a termite, and insects, is flammable, and does not form dust harmful to a worker when it is being cut, punched or lathed. Therefore, it is suitably used as a material for producing a component of furniture.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to composite materials, and in particular to lightweight fiber reinforced cement materials. [Background technology]

[0002] This application claims priority to Thai Patent Application No. 2001002669, filed on May 15, 2020, the disclosure of which is incorporated herein by reference in its entirety.

[0003] In recent years, housing construction, both in the form of apartment complexes and condominiums, has expanded to meet the needs of a growing population. This has also led to growing demand for furniture, driven by modern consumer behavior, which is increasingly choosing furnished homes. Materials used to manufacture furniture for residential interiors can be classified into several types, such as natural wood, synthetic wood, or plastic. These materials can be beautified by carving or covering with leather or other surface coverings. Synthetic wood materials, such as medium-density fiberboard (MDF), plywood, glued laminated lumber, particle board, and plastic, are commonly used to manufacture furniture components due to their low cost, light weight, and ease of cutting and assembly. However, their disadvantages include a short service life due to their lack of resistance to moisture and fungi, termite infestation, and flammability.

[0004] To overcome the above drawbacks, developments have been made to use fiber-reinforced cement materials in the manufacture of furniture components instead of natural and synthetic wood materials. The use of fiber-reinforced cement materials allows for the production of furniture products that are resistant to moisture, fungi, and termites, and are non-flammable. However, other drawbacks are introduced. For example, the density of fiber-reinforced cement materials is higher (i.e., about 1.2-1.7 g / cm) compared to the density of natural and synthetic wood materials. 3, generally), furniture products made of fiber-reinforced cement materials are heavier for the same volume than those made of natural or synthetic wood materials, making them inconvenient to move and transport. Furthermore, fiber-reinforced cement materials are not easy to cut into the shape of furniture products, making it difficult to fasten the furniture products using nails or screws. These drawbacks have led to attempts to develop fiber-reinforced cement materials that are lightweight, easy to cut, and easy to drill holes for screws or nail, while maintaining the properties of being resistant to moisture, fungi, termites, and insects, and being flammable.

[0005] In the prior art, developments to reduce the density of fiber reinforced cement materials have focused on materials with densities of about 0.8 g / cm 3 This has been achieved by using the following materials as constituent materials, such as expanded perlite, expanded vermiculite, volcanic ash, hollow ceramic microspheres, etc. Thai Petty Patent No. 4075 provides a fiber-reinforced cement material containing crushed rice husk, which is used to form tile products. The tile products have a density of 0.89 g / cm3. 3 They are lightweight, with a density nearly equal to that of wood material, have an appearance similar to wood, and require less nailing force. However, their toughness is reduced, and therefore the products cannot be re-fixed multiple times to the same screw position, as required for furniture component applications. Furthermore, Thai Patent Application No. 1401004753 discloses lightweight tile products molded from fiber-reinforced cement materials containing rice husk ash or agricultural waste ash. The tile products have a density of about 1.2 g / cm. 3 or less, which is lower than the density of typical construction tile products molded from fiber-reinforced cement materials. The product is lightweight, easily sawn, cut, or lathed to shape, and easily fastened using nails, but disadvantages include its high brittleness when cut with ordinary woodworking tools, low toughness, inability to refasten multiple times in the same screw location, and production of fine powder that is harmful to workers' health.

[0006] The above drawbacks have driven further development of fiber reinforced cement materials to improve their properties so that they can be more suitable for the manufacture of furniture parts. Specifically, the fiber reinforced cement materials must have low density, high toughness and flexural strength so that the furniture parts can be easily cut or lathed to the desired shape, drilled and re-fixed in the same position with nails or screws multiple times, and do not produce harmful fine powder when cut. Summary of the Invention [Problem to be solved by the invention]

[0007] It is an object of the present invention to provide a fiber reinforced cement composition having low density, high toughness and high flexural strength for use as a material for manufacturing furniture parts, which fiber reinforced cement composition does not contain volatile substances, can be formed into lightweight fiber reinforced cement materials or furniture parts, can be worked using ordinary woodworking tools, cut or lathed to desired shapes, and can be drilled or re-fixed in the same position with nails or screws multiple times. [Means for solving the problem]

[0008] The present invention achieves the above objectives by providing a fiber reinforced cement composition comprising cement, fiber, silica, a filler, expanded perlite, and a polymer.

[0009] In a preferred embodiment, the density of the fiber reinforced cement composition is from about 0.8 to about 0.9 g / cm 3 The range is.

[0010] In a more preferred embodiment, the flexural strength of the fiber reinforced cement composition is in the range of about 9.5 to about 12 MPa.

[0011] In a more preferred embodiment, the toughness of the fiber reinforced cement composition is from about 2,100 to about 2,300 J / m 2 The range is.

[0012] In a more preferred embodiment, the fiber reinforced cement composition has expanded perlite in an amount ranging from about 5% to about 15% by weight.

[0013] In a further preferred embodiment, the fiber reinforced cement composition has an amount of polymer ranging from about 5% to about 15% by weight. More preferably, the polymer is in the form of a powder, slurry, or suspension and is selected from the group consisting of acrylonitrile-butadiene-styrene, polyethylene and its derivatives, vinyl acetate and its derivatives, and any combination thereof.

[0014] In a more preferred embodiment, the fiber reinforced cement composition has an amount of cement in the range of about 20% to about 40% by weight.More preferably, the cement is a hydraulic cement.

[0015] In a further preferred embodiment, the fiber reinforced cement composition according to any one of the preceding claims has fibers in an amount ranging from about 5% to about 10% by weight. More preferably, the fibers are natural fibers, including cellulose fibers, or at least one synthetic fiber selected from the group consisting of polyvinyl alcohol fibers, polypropylene fibers, and any combination thereof.

[0016] In a further preferred embodiment, the fiber reinforced cement composition has an amount of silica ranging from about 30% to about 50% by weight. More preferably, the silica is selected from the group consisting of crushed sand, fly ash, ground bottom ash, ground rice husk ash, ground quartz, silica fume, microsilica, ground mirror, ground glass, ground blast furnace slag, and any combination thereof.

[0017] In a further preferred embodiment, the fiber reinforced cement composition has a filler amount ranging from about 3% to about 15% by weight. More preferably, the filler is selected from the group consisting of calcium carbonate powder, marl powder, kaolin powder, and any combination thereof.

[0018] In a further preferred embodiment, the fiber reinforced cement composition further comprises an additive comprising a colorant.

[0019] In a further embodiment, the present invention provides a fiber reinforced cement composite formed from a fiber reinforced cement composition according to the present invention.

[0020] In a further embodiment, the present invention provides a furniture article made from a fiber reinforced cement material according to the present invention.

[0021] The foregoing objects and embodiments of the present invention will become apparent from a reading of the disclosure of preferred embodiments of the invention set forth in the detailed description. DETAILED DESCRIPTION OF THE INVENTION

[0022] The present invention relates to a composition for a fiber reinforced cement material whose properties are improved to have low density, light weight, high toughness, high bending strength, and can be drilled and re-fixed in the same position with nails or screws many times, and therefore is suitable for use as a material for manufacturing furniture parts.

[0023] The fiber reinforced cement composition according to the present invention comprises cement, fiber, silica, expanded perlite, and a polymer, and may further comprise fillers, additives, and water. In preparing the composition for forming the fiber reinforced cement material, the components of the composition are mixed in a mixing tank in the following preferred component ratios: - cement in the range of about 20% to about 40% by weight; - fiber in the range of about 5% to about 10% by weight; - silica in the range of about 30% to about 50% by weight; - expanded perlite in the range of about 5% to about 15% by weight; - in the range of about 5% to about 15% by weight of polymer; - a filler in the range of about 3% to about 15% by weight; and - Additives and water to make up to 100% by weight.

[0024] A non-limiting example of a preferred cement is a hydraulic cement.

[0025] The fibers to be used may be natural or synthetic. Non-limiting examples of preferred natural fibers include cellulose fibers. Non-limiting examples of preferred synthetic fibers include polyvinyl alcohol fibers, polypropylene fibers, and any combination thereof. The fibers may be organic or inorganic.

[0026] The silica to be used may be any material containing silica. Non-limiting examples of suitable silica include crushed sand, fly ash, ground bottom ash, ground rice husk ash, ground quartz, silica fume, microsilica, ground mirror, ground glass, ground blast furnace slag, and any combination thereof.

[0027] Here, expanded perlite is perlite that has been subjected to a heating process that causes the material to expand, thereby resulting in a lightweight perlite material. Typically, perlite that has not been subjected to a heating process has a density of about 1.1 g / cm 3 However, the density of typical expanded perlite is about 0.03 to 0.15 g / cm 3 is.

[0028] Preferably, the polymer to be used includes acrylonitrile-butadiene-styrene, polyethylene and its derivatives, vinyl acetate and its derivatives, and any combination thereof. With respect to the blending, the polymer may be in the form of a powder, a slurry, or a suspension.

[0029] The filler to be used may be any filler commonly used in this field. Non-limiting examples of preferred fillers include calcium carbonate powder, marl powder, kaolin powder, and any combination thereof.

[0030] Colorants may be used as additives to improve the aesthetic appearance of the finished product.

[0031] The prepared fiber-reinforced cement composition can be molded into a fiber-reinforced cement material for producing furniture parts. Any suitable molding method commonly used in this field may be used, such as the Hatschek process, the Magnani process, injection molding, extrusion molding, hand molding, die casting, filter press, flow-on mechanical process, or roll molding process. Preferred methods include the Hatschek process, extrusion molding, and flow-on mechanical process. The fiber-reinforced cement composition according to the present invention can be molded into a desired shape and size by using a cutting tool or a high-pressure water jet.

[0032] The product is formed by placing the prepared composition in a mold and curing the composition for 4 hours in a room where the temperature is controlled to 80°C or less and the relative humidity is controlled to 50% or more. The cured material is then placed in an autoclave where the temperature is controlled to at least 120°C and the pressure is controlled to a range of approximately 6 to 10 atm for at least 4 hours to obtain a fiber-reinforced cement material product. The material is further dehumidified at a temperature in the range of 60°C to 160°C for at least 1 hour to obtain a lightweight fiber-reinforced cement material product. The product can be surface scrubbed, cut, and / or lathed to form furniture parts of the desired shape and size. [Example]

[0033] The present invention will become clear from the following description, which illustrates examples of the present invention and is not intended to limit the technical spirit of the present invention. The advantageous features of the present invention will become clear with reference to examples of the present invention and comparative examples.

[0034] Comparative Example 1 A fiber-reinforced cement composition free of expanded perlite and polymer components was prepared by mixing 30% hydraulic cement (as a cement component), 7% cellulose fiber (as a fiber component), 40% crushed sand (as a silica component), and 23% calcium carbonate powder (as a filler component) in water. The prepared composition was molded into a plate and cured for at least 4 hours in a room where the temperature was controlled between 40 and 80°C and the relative humidity was controlled between 50 and 100%. The cured plate was then placed in an autoclave where the temperature was controlled between 120°C and the pressure was controlled between 6 and 10 atm for at least 4 hours, and then dehumidified at a temperature between 60 and 160°C for at least 1 hour to obtain a lightweight fiber-reinforced cement material product. The product was tested for flexural strength using a flexural strength testing machine based on the ISO 8336 standard, toughness using a flexural strength testing machine and energy calculation using the area under the flexural strength curve per cross-sectional area at break, density using a test method based on the ISO 8336 standard, thickness swelling using a test method based on the BS EN 317 standard, nail resistance in terms of force per penetration depth using a test method based on the ASTM D1037 standard, and the number of times a screw could be screwed into the same position was counted by screwing a 3.8-4mm diameter screw into the product to a depth of 10-20mm, removing the screw from the product, and repeating this procedure until the screw could no longer be screwed into the same position. The product had a flexural strength of 12.7MPa and a toughness of 973J / m 2 and the density is 1.31 g / cm 3 It was found that the thickness swelling was 0.25%, the nailing resistance was 127.2 N / mm, and the number of times a screw could be screwed into the same position was three.

[0035] Comparative Example 2 A fiber-reinforced cement composition containing no expanded perlite component but containing a polymer component was prepared by mixing 30 wt. % hydraulic cement (as the cement component), 7 wt. % cellulose fiber (as the fiber component), 40 wt. % crushed sand (as the silica component), 10 wt. % acrylonitrile-butadiene-styrene (as the polymer component), and 13 wt. % calcium carbonate powder (as the filler component) in water. The prepared composition was molded into a lightweight fiber-reinforced cement material product, and tested for flexural strength, toughness, density, thickness swelling, nail resistance, and the number of times a screw could be driven into the same position using the methods described in Comparative Example 1. The product had a flexural strength of 12.17 MPa and a toughness of 2,414 J / m 2 and the density is 1.07 g / cm 3 It was found that the thickness swelling was 0.25%, the nailing resistance was 65.7 N / mm, and the number of times that a screw could be screwed into the same position was 101 times.

[0036] Example 1 A fiber-reinforced cement composition containing an expanded perlite component and a polymer component was prepared by mixing 30 wt. % hydraulic cement (as the cement component), 7 wt. % cellulose fiber (as the fiber component), 40 wt. % crushed sand (as the silica component), 5 wt. % expanded perlite (as the expanded perlite component), 10 wt. % acrylonitrile-butadiene-styrene (as the polymer component), and 8 wt. % calcium carbonate powder (as the filler component) in water. The prepared composition was molded into a lightweight fiber-reinforced cement material product, and the flexural strength, toughness, density, thickness swelling, nail resistance, and number of times a screw could be driven into the same position were tested using the methods described in Comparative Example 1. The product had a flexural strength of 11.14 MPa and a toughness of 2,211 J / m 2 and the density is 0.89 g / cm 3 It was found that the thickness swelling was 0.30%, the nailing resistance was 57.3 N / mm, and the number of times that a screw could be screwed into the same position was 97 times.

[0037] Example 2 A fiber-reinforced cement composition containing an expanded perlite component and a polymer component was prepared by mixing 30 wt. % hydraulic cement (as the cement component), 7 wt. % cellulose fiber (as the fiber component), 40 wt. % crushed sand (as the silica component), 10 wt. % expanded perlite (as the expanded perlite component), 10 wt. % acrylonitrile-butadiene-styrene (as the polymer component), and 3 wt. % calcium carbonate powder (as the filler component) in water. The prepared composition was molded into a lightweight fiber-reinforced cement material product, and the flexural strength, toughness, density, thickness swelling, nail resistance, and number of times a screw could be driven into the same position were tested using the methods described in Comparative Example 1. The product had a flexural strength of 10.04 MPa and a toughness of 2,157 J / m 2 and the density is 0.81 g / cm 3 It was found that the thickness swelling was 0.33%, the nailing resistance was 47.6 N / mm, and the number of times that a screw could be screwed into the same position was 93.

[0038] Example 3 A fiber-reinforced cement composition containing an expanded perlite component and a polymer component but no filler component was prepared by mixing 30 wt. % hydraulic cement (as the cement component), 7 wt. % cellulose fiber (as the fiber component), 40 wt. % crushed sand (as the silica component), 13 wt. % expanded perlite (as the expanded perlite component), and 10 wt. % acrylonitrile-butadiene-styrene (as the polymer component) in water. The prepared composition was molded into a lightweight fiber-reinforced cement material product, and tested for flexural strength, toughness, density, thickness swelling, nail resistance, and the number of times a screw could be driven into the same position using the methods described in Comparative Example 1. The product had a flexural strength of 9.50 MPa and a toughness of 2,028 J / m 2 and the density is 0.78 g / cm 3 The thickness swelling was 0.44%, the nailing resistance was 38.2 N / mm, and the number of times a screw could be screwed into the same position was 87 times.

[0039] [Table 1]

[0040] Table 1 summarizes the amounts of components of the fiber-reinforced cement material and the test results of the lightweight fiber-reinforced cement products obtained in the above-mentioned comparative examples and examples of the present invention. By comparing the test results between Comparative Example 1 (not including expanded perlite and polymer components) and Comparative Example 2 (including polymer components but not expanded perlite components), it can be seen that adding a polymer component to replace the amount of the filler component (i.e., by adding 10 wt% of polymer component and reducing the amount of filler component from 23% to 13 wt%) reduces the density of the fiber-reinforced cement product (from 1.31 to 1.07 g / cm 3 ), and toughness increased (from 973 to 2,414 J / m 2 ), the nailing resistance decreases (from 127.2 to 65.7 N / mm), and the number of times a screw can be screwed into the same position in the product increases (from 3 to 101 times).

[0041] By comparing the test results between Comparative Example 2 (containing a polymer component but not an expanded perlite component) and Examples 1 to 3 (containing a polymer component and an expanded perlite component), it was found that, for the same amounts of cement component, fiber component, and polymer component (30 wt% cement component, 40 wt% silica component, 7 wt% fiber component, and 10 wt% polymer component), adding an expanded perlite component to replace the amount of the filler component (i.e., in Example 1, the amount of the filler component was reduced from 13% to 8 wt% while adding 5 wt% expanded perlite component; in Example 2, the amount of the filler component was reduced from 13% to 3 wt% while adding 10 wt% expanded perlite component; and in Example 3, the amount of the filler component was reduced from 13 wt% to zero while adding 13 wt% expanded perlite component), resulted in a decrease in the density of the fiber-reinforced cement product (from 1.07 to 0.89, 0.81, and 0.78 g / cm, respectively). 3 ), nail resistance decreased (from 65.7 to 57.3, 47.6 and 38.2 N / mm, respectively), while toughness decreased (from 2,414 to 2,211, 2,157 and 2,028 J / m2 It can be seen that there are slight differences in the thickness swelling (from 0.25% to 0.30%, 0.33% and 0.44%, respectively) and the number of times that a screw can be screwed into the same position in the product (from 101 times to 97 times, 93 and 87 times, respectively). These results show that the fiber reinforced cement material of the present invention has properties close to those of natural or synthetic wood materials, and is also advantageous due to its characteristics of being resistant to moisture, termites and insects, being non-flammable, and not producing harmful fine powders that are harmful to workers' health when cutting, drilling and / or turning.

[0042] Although the present invention has been described in full detail above, it will be understood by those skilled in the art that various changes and modifications can be made thereto without departing from the spirit and scope of the present invention. The scope of the present invention is limited by the appended claims and is intended to cover features of the invention not specifically recited in the claims but having substantially the same properties, functions, and effects as those recited in the claims.

[0043] Best Mode of the Invention Same as explained in full detail above.

Claims

1. A fiber-reinforced cement composition formed into a plate and used as a material for manufacturing furniture parts, comprising: The composition comprises: 30% by weight of cement; 7% by weight of fibers; 40% by weight of silica; 0% to 8% by weight of a filler; 5% to 13% by weight of expanded perlite; 10% by weight of a polymer selected from the group consisting of acrylonitrile-butadiene-styrene, polyethylene and its derivatives, vinyl acetate and its derivatives, and any combination thereof.

2. The fiber reinforced cement composition according to claim 1, having a density of 0.8 to 0.9 g / cm ３ The composition characterized in that the range of

3. 10. The fiber reinforced cement composition of claim 1, wherein the composition has a flexural strength in the range of 9.5 to 12 MPa.

4. 2. The fiber reinforced cement composition according to claim 1, wherein the toughness is 2,100 to 2,300 J / m ２ The composition characterized in that the range of

5. 10. The fiber reinforced cement composition of claim 1, having an amount of said expanded perlite ranging from 5% to 15% by weight.

6. 10. The fiber reinforced cement composition of claim 1 having an amount of said polymer in the range of 5% to 15% by weight.

7. 7. The fiber reinforced cement composition of claim 6, wherein the polymer is in the form of a powder, a slurry, or a suspension.

8. 10. The fiber reinforced cement composition of claim 1, having an amount of said cement in the range of 20% to 40% by weight.

9. 9. The fiber reinforced cement composition of claim 8, wherein the cement is a hydraulic cement.

10. 10. The fiber reinforced cement composition of claim 1, having an amount of said fibers in the range of 5% to 10% by weight.

11. 11. The fiber reinforced cement composition of claim 10, wherein the fibers are natural fibers.

12. 12. The fiber reinforced cement composition of claim 11, wherein the natural fibers are cellulose fibers.

13. 11. The fiber reinforced cement composition of claim 10, wherein the fibers are synthetic fibers.

14. 14. The fiber reinforced cement composition of claim 13, wherein the synthetic fibers are selected from the group consisting of polyvinyl alcohol fibers, polypropylene fibers, and any combination thereof.

15. 10. The fiber reinforced cement composition of claim 1, having an amount of said silica in the range of 30% to 50% by weight.

16. 16. The fiber reinforced cement composition of claim 15, wherein the silica is selected from the group consisting of crushed sand, fly ash, ground bottom ash, ground rice husk ash, quartz powder, silica fume, microsilica, crushed mirror, crushed glass, crushed blast furnace slag, and any combination thereof.

17. 10. The fiber reinforced cement composition of claim 1, having an amount of said filler in the range of 3% to 15% by weight.

18. 18. The fiber reinforced cement composition of claim 17, wherein the filler is selected from the group consisting of calcium carbonate powder, marl powder, kaolin powder, and any combination thereof.

19. 10. The fiber reinforced cement composition of claim 1, further comprising an additive comprising a colorant.

20. A fiber reinforced cement composite material for the manufacture of furniture parts, characterized in that the fiber reinforced cement composite material is formed from the fiber reinforced cement composition described in claim 1.

21. A furniture product made from the fiber reinforced cement composition of any one of claims 1 to 19, or made from the fiber reinforced cement composite material of claim 20.

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