JPH03275546A - Production of noncombustible composite molded body - Google Patents

Abstract

PURPOSE:To reduce weight and to improve mechanical characteristics and noncombustibility by impregnating a sol-gel binder made from metal alkoxide into a base material obtd. by mixing inorg. grains with thermosetting resin and drying the binder. CONSTITUTION:A mixture of 1l inorg. grains of 100-300mum average grain size such as sand with 20-150g uncured thermosetting resin is molded into a desired shape and cured by heating to obtain a base material. A sol-gel binder made from metal alkoxide is impregnated into the base material and hardened by heating to 100-300 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for manufacturing a noncombustible composite molded article used as a noncombustible building material.

(Prior Art) In recent years, with the diversification of buildings, the performance of building materials has improved, and as a result, many plastic building materials have come to be used as interior or exterior materials. Compared to cement-based building materials, these plastic building materials are lightweight, have excellent heat insulation properties, environmental resistance against humidity and freezing, decorative properties, and productivity/processability, but on the other hand, they are flammable. Because of this nature, when a fire breaks out, it tends to spread easily and generates a lot of harmful gases.

In order to improve these drawbacks, the amount of plastic used should be kept to the minimum necessary for molding building materials, and flame retardants such as aluminum hydroxide should be added, and phenolic resins, which are low smoke-emitting resins, should be used for plastics. Various countermeasures such as these have been attempted.

For example, Japanese Patent Application Laid-Open No. 60-3346 discloses that lightweight inorganic materials such as fired perlite and shirasu balloons are hardened and molded with phenol resin or the like to be used as a building material.

(Problems to be Solved by the Present Invention) However, the conventional building materials described above have a problem in that the requirements for strength and nonflammability of the molded body cannot be sufficiently achieved at the same time.

The present invention has been made to solve the above-mentioned problems, and its purpose is to promote a method for producing a nonflammable composite molded article having excellent mechanical properties and nonflammability.

(Means for Solving the Problems) The method for producing a nonflammable composite molded body of the present invention includes adding and mixing 20 to 150 g of uncured thermosetting resin to 12 volumes of inorganic powder and granules, and After that, a base material is formed by heating and curing to bond inorganic powder and granules together with a resin, and this base material is impregnated with a sol-gel binder made from a metal alkoxide as a raw material, and then dried. It is.

Examples of the inorganic powder used in the present invention include sand,
Silica sand, natural rock granules, diatomaceous earth, shirasu, alumina,
Natural sand and minerals such as clay, kaolin, and talc; artificial materials and waste materials such as pottery powder, porcelain powder, glass powder, and coal ash; hydroxides such as aluminum and calcium; Carbonates, sulfates, silicates, or those containing crystal water, as well as lightweight granules such as perlite, vermiculite, glass balloons, shirasu balloons, coal ash balloons, and ceramic balloons, were selected from these. It is at least one kind or more.

In the present invention, the inorganic powder and granules are not particularly limited, but in order to obtain a high-strength and non-flammable molded body, the average particle size (50% particle size in the particle size distribution measured by standard sieve measurement) is 1l00.
Inorganic powder or granules having a particle size of a or more are preferably used. If the average particle size is less than 100 μm, the specific surface area increases, so a large amount of resin is required to bind the inorganic powder with the resin, and as a result, nonflammability cannot be ensured.

Further, in order to prevent the surface smoothness from becoming poor, inorganic powder having an average particle size of 300 μm or less is preferably used, but there is no particular limitation. These inorganic powders may be treated with a coupling agent such as aminosilane or acrylic silane for the purpose of improving interfacial adhesion with the thermosetting resin.

The uncured thermosetting resin used in the present invention is liquid or powder, and is molded by mixing with the inorganic powder and granules, since polymerization proceeds with a crosslinking reaction in the presence of a curing agent. It can provide liquidity. Examples of such thermosetting resins include phenol resins, urea resins, melamine resins, furan resins, epoxy resins, and unsaturated polyester resins. In particular, it is preferable to use a novolak type phenol resin as the phenol resin because it can improve the nonflammability and mechanical properties.

Furthermore, in order to improve the bonding strength between the inorganic powders and granules, a method of pre-coating the inorganic powders with a novolac type phenol resin is preferably used.

The amount (composition ratio) of the thermosetting resin is as follows: Inorganic powder II! The ratio is limited to a weight of 20 to 150 g to the capacity; if the weight is less than 20 g to the If capacity of the inorganic powder or granule, the strength of the molded product is low and does not satisfy the mechanical properties as a building material. However, if the weight exceeds 150 g, the mechanical properties will improve, but it will not be possible to ensure nonflammability.

In the present invention, a base material in which the inorganic powder and granules are bonded together with a resin is constructed by mixing the above-mentioned inorganic powder and a thermosetting resin and curing the mixture with heat. Additives and fillers can be used as appropriate insofar as they do not significantly impair lightweight properties, mechanical properties, and nonflammability. Examples of additives include heat stabilizers, ultraviolet absorbers, antioxidants, pigments, dyes, antistatic agents, fungicides,
A flame retardant can be used as appropriate, and as the reinforcing filler, inorganic powder, inorganic fiber, etc. can be used.

In the present invention, the method of molding the base material from the above-mentioned mixture of inorganic powder and granular material and thermosetting resin is a method of heating and curing in a mold, and involves a process of filling, shaping (heat curing) and releasing. It consists of a series of methods. For example, heat curing methods include filling a pre-heated mold with the above mixture and rapidly curing it, or curing the surface layer of the base, releasing it from the mold, and then thoroughly curing the inside in a heating oven. is adopted, but is not limited to this. As described above, in the present invention, in addition to the heat curing method, the heating temperature and time, the shape and dimensions of the base material, etc. are not particularly limited.

The sol-gel binder in the present invention refers to Si, A
I! Using an alkoxide, which is an organometallic compound such as Ti or Zr, as a starting material, a sol body obtained by forming a metalloxane polymer through the process of hydrolysis and dehydration condensation as shown in the following formula,
This is a specific inorganic adhesive that is made into an inorganic gel, ie, a cured product, by dehydrating and dealcoholizing this sol by heating.

M(oR)p + QH! 0 → M(01l)Q (OR)p-q + qROH(hydrolysis)n (M(OH)Q (OR)p-q) →(
M(OR)(OH)0 ) −+ nHtO (dehydration condensation) (usually p=4.q・2) This metalloxane polymer has the following properties:
Alternatively, a solvent, a dispersant, a curing catalyst, and a filler may be appropriately blended to stabilize the film.

That is, in the present invention, the blend of the metalloxane polymer described above is used as a blue gel binder.

In order to infiltrate the sol-gel binder between the inorganic particles of the base material, for example, immersion in a sol-gel binder solution adjusted to an appropriate viscosity, or by reducing or pressurizing the sol-gel binder. A method of forcibly injecting the binder into the inside of the base material from the surface is effective.

In the present invention, the sol-gel binder is cured mainly by heating, preferably at a temperature of 100 to 300
Achieved in an atmosphere of °C. If it is cured at a temperature exceeding 300°C, the thermosetting resin component of the base material will undergo thermal decomposition during heat curing, which will significantly reduce the mechanical properties of the final molded product, which is undesirable. If the temperature is less than 100°C, the metalloxane polymer tends to be insufficiently cured (it tends to be difficult to obtain thermal stability of the film that covers the thermosetting resin of the base material. Preferably, the cured film of the sol-gel binder covers 40% or more of the total surface area of the thermosetting resin bonding the inorganic powder.
The average thickness of the coating is preferably 5 μm or more. This is because, if the film is sufficiently formed on the thermosetting resin, the thermosetting resin is effectively protected by the sol-gel binder film and improving its nonflammability.

(Function) According to the method for producing a nonflammable composite molded body of the present invention, a large amount of inorganic powder is mixed with a very small amount of uncured organic thermosetting resin, and the mixture is molded. When heated and cured in a mold, a base material is obtained in which particles of the inorganic powder are bonded and bonded together by the thermosetting resin. The base material has voids between the inorganic particles inside the base material, which communicate with the surface portion. When the sol-gel binder is infiltrated between the inorganic particles, the surface of the base material and the surface of the hardened thermosetting resin in the internal voids are coated with the sol-gel binder. When this sol-gel binder is gelled, a hardened inorganic film is formed on the surface of the thermosetting resin. This film protects the thermosetting resin and improves its nonflammability.

(Example) Examples and comparative examples of the present invention are shown below.

Dirty sand (classified product, average particle size 260 μta) II! and unsaturated polyester resin (Dainippon Ink & Chemicals Co., Ltd.: Bolilite TP160)
After adding 60 g of benzoyl peroxide and 1.2 g of benzoyl peroxide as a catalyst and stirring and mixing for 3 minutes, the mixture was taken out and placed in a metal mold (250 x 250
12mm and 150 x 100 x 4 a+s+
) was filled into a cup and heated in a heating furnace at 150°C for 10 minutes, and then the base material was taken out from the mold.

Next, the molded body is placed in a desiccator filled with a sol-gel binder (GLACERAM GC#330 manufactured by Shinto Toyo Co., Ltd.), and the pressure is further reduced with an aspirator to release the gas contained inside the base material. By replacing the molded product with the liquid of the sol-gel binder in a vacuum, the voids between the inorganic particles of the molded body were completely saturated with the sol-gel binder. Thereafter, the base material was taken out and left in a hot air dryer at 150°C for 40 minutes to gel and harden the sol-gel binder.

The flexural strength, flexural modulus, and nonflammability of the obtained noncombustible composite molded article were evaluated. The evaluation was good in all test items. The results are shown in Table-1. The bending test was conducted using 80 x 10
Create a test piece of X 4s+a+ and JISK 7203
This was done in accordance with the. In addition, the nonflammability test is based on the Ministry of Construction Public Notice No. 1828 (December 28, 1972) based on the Building Standards Act, and the base material test and surface test are 40 x 40 x 50 m5 and 250 x 250 m5, respectively.
A test piece of X12- was prepared and judged as pass/fail (marked with O for a passed test and marked with an X for a failed test).

Example 1 A molded article was obtained in the same manner as in Example 1 except that the weight of the unsaturated polyester was 120 g and the weight of benzoyl peroxide was 2.4 g, and an evaluation test thereof was conducted.

The evaluation was good in all test items.

The results are shown in Table-1.

In an Eirich mixer, add 1 liter of dirty sand (classified product, average particle size 260 μm) preheated to 150 to 160°C and a novolac type phenol resin (Castol D H-402 manufactured by Dainippon Ink and Chemicals). ) 40g and stirred and mixed for 1 minute, then 6g of hexamethylenetetramine and 20g
of water and stirred until the clumps of the sludge mixture disintegrated into powder. followed by calcium stearate 1
g was added thereto, and after further stirring for 30 seconds, the mixture was taken out from the mixer to obtain dirty sand coated with a novolak type phenol resin.

Next, a metal mold (250 x 250 x l 2
ms+ and 150 x 100 x 4 mm) and heated in a heating oven at 190 °C for 10 minutes.
The base material was taken out from this mold. This base material was impregnated with a sol-gel binder in the same manner as in Example 1 to obtain a nonflammable molded article, and an evaluation test was conducted. The evaluation was good in all test items. The results are shown in Table-1.

A similar evaluation test was conducted for Example 1 in which the infiltration with the sol-gel binder was not performed. The results are shown in Table-1.

Mosquito box I 170g of unsaturated polyester, 3.0g of benzoyl peroxide.
A nonflammable molded article was obtained in the same manner as in Example 1 except that the amount was 6 g, and an evaluation test was conducted. The results are also shown in Table-1.

Table 1 (Note) Type of this resin UP: Unsaturated polyester PH: Nonerafuku type phenol Resin amount to Kyrimethylene to Kypmin ratio Resin amount is Resin amount to inorganic powder 21 (Effect of the invention) As described above, the present invention The noncombustible composite molded article obtained by the manufacturing method is lightweight and has excellent mechanical properties, and is recognized as a noncombustible material in the fire protection material test according to Ministry of Construction Publication No. 1828.

Claims (1)

[Claims] 1. Add and mix 20 to 150 g of uncured thermosetting resin to 1 liter of inorganic powder and granule, and then heat cure to form a base material in which the inorganic powder and granule are bonded together with resin. 1. A method for producing a nonflammable composite molded article, which comprises molding, impregnating the base material with a sol-gel binder made from a metal alkoxide, and drying.