JPH0485023A - Manufacture porous hollow composite sheet - Google Patents

Abstract

PURPOSE:To obtain a porous hollow composite sheet which is lightweight and excellent in fire resistance, safety, design properties and folding resistance by forming W/O-type emulsion contg. cement of vinyl monomer, cement, water and synthetic fiber and extruding the said emulsion into a porous hollow shape. CONSTITUTION:W/O-type emulsion contg. cement wherein reinforcing fiber is sufficiently dispersed is obtained by continuously supplying 307.8kg/hr portland cement, 275.4kg water, 16.0kg/hr vinyl monomer soln. and 5kg/hr acrylic fiber having 333 aspect ratio and 6mm length to a continuous kneader. The said emulsion is continuously supplied to an extruder equipped with a die for hollow molding. A porous hollow sheet having 30mm thickness, 455mm width and 25% percentage of hollowness is continuously extruded at 0.3kg/cm<2> extrusion pressure. A perforated hollow sheet having 0.75 sp. gr. is obtained by aging the porous hollow sheet by steam at 50 deg.C for 17 hours and at 90 deg.C for 24 hours to cure it and thereafter drying it. Melamine-baked iron sheet having 0.6mm thickness is laminated on both sides of this porous hollow molded sheet by an epoxy-based adhesive.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a highly safe cement-based porous hollow composite board that does not contain asbestos fibers and has plate-like sheet materials adhered to its front and back surfaces. This relates to a manufacturing method. The porous hollow composite board obtained by the method of the present invention has excellent fire resistance, light weight, safety, design, and bending resistance, and is therefore suitable for use as an interior board for buildings.

[Conventional technology] Previously, inorganic composite boards were reinforced with asbestos fibers? ,
: Commonly, a metal plate was attached to a foamed cement board, or a metal plate that had undergone actual processing was poured with cement slurry and allowed to harden.

[Problem R to be solved by the invention] The above-mentioned conventional asbestos-reinforced inorganic composite board has the following problems:
Because asbestos fibers pose a significant risk to human health, there has been a strong demand for asbestos-free materials.

In addition, the conventional cement composite board to which the metal plate is attached has poor adhesion to the metal plate due to poor compatibility between the cement composite board and the adhesive, and the reinforcement effect of the metal plate cannot be obtained sufficiently.

Furthermore, composite plates made by pouring cement slurry into a metal plate that has been subjected to actual processing and curing cannot be expected to have strong adhesion to the metal plate, making it difficult to produce long pieces.

[Means for Solving the Problems] The present invention provides a cement-containing W/O in which reinforcing fibers obtained from a water-insoluble monomer containing a polymerization initiator and an inverse emulsifier, cement, water, and synthetic fibers are dispersed. The mold emulsion is extruded into a porous hollow shape, and cured by natural curing, steam curing, or autoclave curing to advance the polymerization reaction of vinyl monomer and the hydration reaction of cement. After hardening, it is dried, and a plate-like material is formed on the front and back surfaces. Alternatively, the present invention provides a method for obtaining a lightweight, porous hollow composite plate having excellent fire resistance, safety, design, and bending resistance by pasting sheet-like materials.

That is, according to the method of the present invention, the reinforcing fibers are extruded into a cement-containing O-type emulsion in which the vinyl monomer becomes a continuous phase and water and cement are dispersed therein. The raw materials are extruded.

Since the continuous phase of the inverse emulsion of this raw material composition, that is, the matrix, is an oil-based vinyl monomer, compared to the conventional raw material composition made of cement-water-soluble polymer compound, it is difficult to use synthetic resin-based reinforcing fibers. Because of its extremely high affinity for reinforcing fibers, it exhibits excellent effects on the dispersibility of reinforcing fibers, the reinforcing effect, and the fluidity of raw materials.

Furthermore, since the cement-containing W/O emulsion of the present invention has thixotropic properties, it will flow when a large external force is applied, but it will not lose its shape when left standing, so it can be easily made into extrudates with many small pores. Obtainable.

In the present invention, the cement-containing W/O emulsion is prepared by adding a water-insoluble vinyl monomer and an inverse emulsifier to a cement slurry consisting of 40 to 500 parts by weight, preferably 50 to 200 parts by weight of water based on parts by weight of cement/O0. , a vinyl monomer solution consisting of a polymerization initiator is added in an amount of 1 to 20% by weight, preferably 2 to 0.0% by weight, and 0.5% by weight is added using a commercially available mixer.
Obtained by stirring for ~5 minutes. Since the cement-containing O/O type emulsion is in the form of oil-based soft clay, it is very compatible with synthetic fibers and can be uniformly dispersed simply by mixing them without any pretreatment.

Examples of the cement used in the present invention include Portland cement, blast furnace cement, fly ash cement, silica cement, silicic acid compounds, and calcium compounds.

As reinforcing fibers, polypropylene, polyester, vinylon, nylon, acrylic, and aramid fibers are used. The reinforcing fibers preferably have an aspect ratio of /O0 to 2000 and a length of 2 to 20II1 m from the viewpoint of reinforcing effect and dispersibility.

The vinyl monomer is preferably liquid at room temperature and poorly soluble in water in order to make it compatible with synthetic fibers when producing a cement-containing W/O emulsion.

Examples include styrene, α-methylstyrene, acrylic ester, methacrylic ester, acrylonitrile, divinylbenzene, acrylic or methacrylic ester of alkylene gelcol, acrylic or methacrylic ester of polyhydric alcohol, and the like. These may be used alone or in combination of two or more. Among the above-mentioned and nil monomers, it is particularly preferable to use a mixture of nil monomers, especially when the main component is styrene.

In addition, dimethacrylate or trimethacrylate compounds of polyhydric alcohols used for the purpose of increasing the strength and polymerization properties of molded products include divinyl and trivinyl compounds such as ethylene gelcol dimethacrylate and trimethylolpropane trimethacrylate. It is preferable to use them together.

A polymerization catalyst is mixed into the vinyl monomer in order to promote curing reaction after molding, and a general radical forming agent or redox catalyst is used as the polymerization catalyst according to a usual recipe.

The inverse emulsifier for forming a cement-containing W/O emulsion is a nonionic surfactant with an HLB value of 3 to 6 dissolved in a proportion of 3 to 50% by weight relative to the vinyl monomer. A cement-containing W/O emulsion is also formed. In the present invention, the HLB value used is 3.
Examples of the nonionic surfactants 6 to 6 include sorbitan monooleate, glycerol monostearate, sorbitan monooleate, diethylene glycol monostearate, sorbitan monostearate, diglycerol monooleate, and maleic anhydride adducts of alkylene glycol. etc. These may be used alone or in combination of two or more. When used alone, sorbitan monooleate and diglycerol monooleate are preferred. In addition, pearlite, vermiculite, shirasu balloons, glass balloons, synthetic resin foams, etc. may be mixed as lightweight aggregates as necessary.

Contains cement including the reinforcing fibers mentioned above! //O-type emulsion 5 is molded using an extrusion molding machine equipped with a die for molding a porous hollow plate having a core that forms a hollow portion at the outlet. The hollow plate referred to in the present invention is a plate-like object in which a large number of columnar hollow holes are formed in parallel to the extrusion direction. The extruded porous hollow molded plate is cured by natural curing, steam curing, and autoclave curing to advance the polymerization of vinyl monomer and the hydration reaction of cement, and is then dried after hardening.

Thereafter, a plate-like object or a sheet-like object is attached to the front and back surfaces using an adhesive.

The plate-like or sheet-like materials include wood-based materials such as plywood, particle board, and fiberboard, plastic-based materials such as styrene, polyester, epoxy, vinyl chloride, melamine, and phenolic resin, and metal-based materials such as iron, aluminum, and stainless steel. In addition to plates or sheets, woven fabrics and non-woven fabrics are used.

These plate-like products or sheet-like products are preferably colored or printed with patterns to give them a design.

There are no particular restrictions on the adhesive used to adhere these plate-like objects or sheet-like objects to the porous hollow plate, but rubber-based, epoxy-based, vinyl acetate-based, and phenol-based adhesives can be used.

The vinyl polymer contained in the porous hollow plate has good compatibility with the adhesive and thus contributes to improved adhesiveness.

[Example] The present invention will be explained in detail in Examples below.

Example 1 Portland cement was fed into a continuous kneader at a rate of 307.
8Kg, 275.4Kg of water, 16°0Kg of vinyl monomer solution per hour, aspect ratio 333, length 6mm
5 kg of acrylic fibers were continuously supplied per hour to obtain cement-containing W/O type emulsion in which reinforcing fibers were well dispersed. The styrene monomer solution is styrene monomer 6.
It was a mixture of 9 parts by weight of sorbitan monooleate, 25 parts by weight of trimethylolpantrimethacrylate, and 1 part by weight of benzoyl peroxide. The obtained cement-containing W/O emulsion was soft clay-like and did not dissolve in water. This cement containing V/O
The emulsion composition was continuously fed into an extruder equipped with a die for blow molding, and a porous hollow plate with a thickness of 30 mm, a diameter of 455 mm, and a hollow ratio of 25% was continuously extruded at an extrusion pressure of 0.3 Kg/cm2. Molded. The obtained extrusion molded plate was heated at 50°C for 1
After being cured with steam for 7 hours and 24 hours at 90°C, it was dried to obtain a porous hollow plate having a specific gravity of 0.75. This porous hollow molded plate maintained the same shape as when it was extruded even after drying, and no deformation or deformation was observed. The bending failure load of this porous hollow molded plate is 30 based on JIS A1408.
It was 330 kg in mm thickness.

Melamine baked iron plates having a thickness of 0.6 mm were adhered to the front and back surfaces of this porous hollow molded plate using an epoxy adhesive. The obtained porous hollow composite plate had excellent strength and design because the iron plate was bonded very firmly.

Example 2 453.6 kg of blast furnace cement per hour, 226.8 kg of water per hour, and 16 kg of vinyl monomer solution per hour in a continuous kneader
．． 0Kg.

Vinylon fibers having an aspect ratio of /O00 and a length of 12n+m were continuously fed at 7.0 kg per hour to obtain a cement-containing W/O emulsion in which reinforcing fibers were well dispersed. However, the vinyl monomer solution was a mixture of 74 parts by weight of styrene monomer, 5 parts by weight of ethylene glycol dimethacrylate, 820 parts by weight of diglyarol monoolet, and 1 part by weight of t-butyl peroxybenzoate. The obtained cement-containing V/O emulsion was soft clay-like and did not dissolve in water. This cement-containing W/O emulsion composition was continuously supplied to an extruder equipped with a die for blow molding, and a hollow plate with a thickness of 18 m+++, 1 g of 455 mm, and a hollow ratio of 30 $ was produced using an extrusion pressure of 0.5 kg/c+a2. Continuously molded. The obtained extrusion-molded plate was cured by steam curing at 50°C for 17 hours and at 90°C for 24 hours, and then dried to obtain a porous hollow-molded plate having a specific gravity of 1.1. This porous hollow molded plate maintained the same shape as when it was extruded even after drying, and no deformation or deformation was observed.

The bending failure load of the obtained porous hollow-formed plate based on JIS A1408 was 180 kg.

A woven fabric was attached to the surface of this porous hollow plate using a rubber adhesive.

The resulting porous hollow composite board had excellent design with the woven fabric firmly adhered to it.

Example 3 Portland cement was fed into a continuous kneader at 162°/hour.
kg, 324.0 kg of water, and 16.0 kg of nil monomer solution per hour, g1 aspect ratio is 500, and length is 6111.
of aramid fiber per hour/O. 0 kg was continuously supplied to obtain a cement-containing W/O emulsion in which reinforcing fibers were well dispersed. However, the monomer solution contains 64 parts by weight of styrene monomer, 30 parts by weight of sorbitan monooleate,
5 parts by weight of trimethylolpropane trimethacrylate,
A mixture of 1 part by weight of t-butylperoxyisopropyl carbonate was added. The obtained cement-containing w/O type emulsion was soft clay-like and did not dissolve in water. This cement-containing V/O emulsion composition was continuously fed into an extruder equipped with a die for forming hollow plates.
．． Thickness 35 with extrusion pressure of 2Kg/cm2! ll11. A hollow plate having a diameter of 455 cm and a hollowness ratio of 20% was continuously extruded.

The obtained extrusion molded plate was steam-cured at 60°C for 8 hours and then
The material was steam-cured in an autoclave for 18M at 35° C., cured, and then dried to obtain a porous hollow-molded plate having a specific gravity of 0.52.

This porous hollow molded plate maintained the same shape as when it was extruded even after drying, and no deformation or deformation was observed.

The bending fracture load of the obtained porous hollow plate based on JIS A1408 was 380 kg at a thickness of 35 mm.

Flame-retardant Chinese plywood with a thickness of 5.5 mm was adhered to the front and back surfaces of this porous hollow board using a vinyl acetate adhesive.

A porous hollow-molded board with excellent design to which plywood was firmly adhered was obtained.

Example 4 54 parts by weight of styrene monomer, parts by weight of acrylonitrile/O, 30 parts by weight of maleic anhydride adduct of polyalkylene glycol with an average molecular weight of 2000, 5 parts by weight of ethylene glycol dimethacrylate, 1 part by weight of benzoyl peroxide, 400 parts by weight of Portland cement Parts by weight, 8 parts water
00 parts by weight, 20 parts by weight of Shirasu balloons, and 13 parts by weight of polypropylene fibers were mixed and stirred in a double-arm kneader to obtain a cement-containing V/O emulsion in which reinforcing fibers were well dispersed. This cement-containing O/O emulsion did not dissolve in water. This cement-containing W/O type emulsion! The composition was heated to zero in an extruder equipped with a blow molding die.
．． 7 to extrusion molding at an extrusion pressure of 12 g/c to a thickness of 35 m.
A porous hollow plate with g+, radius 455 mm, and hollowness ratio 20X was molded. This hollow plate was left open at room temperature for 28 days, and after hardening and drying, the specific gravity was 0.45. This porous hollow plate maintained the same shape as when it was extruded, and there was no deformation or loss of shape, and no destruction of the shirasu balloon was observed.

The bending failure load of the obtained porous hollow plate based on JIS A1408 was 350 kg at a thickness of 35 m+++.

Melamine plates were attached to the front and back surfaces of this porous hollow plate using an epoxy adhesive, and the bond was strong and showed excellent robustness.

Comparative Example 1 60 parts by weight of Portland cement, 12 parts by weight of silica sand,
After mixing 12 parts by weight of asbestos, 20 parts by weight of Shirasu balloons, and 1 part by weight of methyl cellulose and dispersing the asbestos well,
Add 60 parts by weight of water to make it clay-like, and extrude it using an extruder equipped with a molding die at an extrusion pressure of 3g/cm2 to a thickness of 18 layers and a diameter of 455 layers. A solid plate was formed by rapid extrusion. The obtained solid board was cured and dried in the same manner as in Example 1, and melamine boards with a thickness of 1 mm were attached to the front and back surfaces using an epoxy adhesive.

The solid board to which this melamine board was attached was not found to have excellent robustness because the melamine board peeled off due to slight bending.

[Effects of the Invention] As described above, the porous hollow composite board obtained by the method of the present invention has a high reinforcing effect because the nyl monomer is compatible with the reinforcing synthetic fiber when included in the cement-containing W/O emulsion. As a result, asbestos-free cement composite boards can be achieved.

Furthermore, the porous hollow composite board of the present invention has good compatibility with adhesives, so that it firmly adheres to plate-like objects or sheet-like objects attached to the front and back surfaces of the porous hollow composite board.
This improves bending resistance and facilitates the production of long products.

Claims (5)

[Claims] (1) After curing and curing a porous hollow extrusion molded plate of a cement-containing W/O type emulsion in which reinforcing fibers obtained from a water-insoluble vinyl monomer containing a polymerization initiator and an inverse emulsifier, water, and synthetic fibers are dispersed. A method for producing a porous hollow composite board, which comprises drying and pasting a plate-like material or a sheet-like material on the front and back surfaces. (2) The method for producing a porous hollow composite board according to claim 1, wherein the plate-like material or sheet-like material to be attached to the front and back surfaces is a wood-based board. (3) The method for producing a porous hollow composite plate according to claim 1, wherein the plate-like object or sheet-like object to be attached to the front and back surfaces is a plastic plate or a plastic sheet. (4) The method for producing a porous hollow composite plate according to claim 1, wherein the plate-like object or sheet-like object to be attached to the front and back surfaces is a metal plate or a metal sheet. (5) The method for producing a porous hollow composite board according to claim 1, wherein the plate-like material or sheet-like material to be adhered to the front and back surfaces is a woven fabric or a non-woven fabric.