JPH03269010A - Production of composite molding of phenol resin - Google Patents

Abstract

PURPOSE:To obtain the title molding useful as a building material, having excellent mechanical properties, environmental resistance, heat insulating properties and incombustibility, by coating specific hollow coal ash particles with a novolak type phenol resin and curing the particles in a mold under heating and making the molding lightweight. CONSTITUTION:Hollow coal ash particles having 50-300mum, preferably 100-200mum average particle diameter and 0.2-0.7, preferably 0.3-0.5 bulk density are coated with 2-10g based on 100cm<2> of the particles of a novolak type phenol resin and are cured in a mold under heating to give the objective molding.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention provides a phenolic resin composite molded article for use in building materials that is lightweight, has excellent mechanical properties, environmental resistance, and heat insulation properties, and is nonflammable. This relates to a manufacturing method.

(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 and exterior materials.

Compared to cement-based building materials, a series of plastic building materials are not only lightweight, have excellent heat insulation properties, and environmental resistance against humidity and frost damage, but also have excellent decorative properties, production and processability, etc. However, since it is flammable under low pressure, it has the disadvantage that in the event of a fire, it is easy to spread and produces a lot of smoke such as harmful gases.

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

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

(111 to be solved by the invention) However, the above-mentioned conventional building materials had a problem in that the requirements for molded body strength and nonflammability were not sufficiently achieved at the same time.

The present invention was developed as a result of intensive studies in view of the above problems, and its purpose is to provide a method for manufacturing a phenolic resin composite molded article that is lightweight and has excellent mechanical properties and nonflammability. Our goal is to provide the following.

(Means for Solving the Problems) The method for producing a phenolic resin composite molded body of the present invention is to produce hollow coal ash particles having an average particle size of 50 to 300μ■ and a bulk specific gravity of 0.2 to 0.7, and a 100CI+ ', 2 to 1
It is characterized in that it is coated with a novolak type phenolic resin in a proportion of 0 g, and then heated and cured in a mold.

The hollow coal ash referred to in the present invention is made hollow by firing and foaming so-called fly ash discharged from coal-fired power plants, and it has a volumetric strength compared to heat-resistant shirasu balloons and glass balloons. is extremely high;
The balloon has a shape close to a perfect sphere, has a high proportion of independent bubbles, and has no defects. Furthermore, since it mainly contains aluminosilicate, it has characteristics such as being inert and stable.

The average particle size of the hollow coal ash used in the present invention (50% particle size in particle size distribution measured by II quasi-sieve measurement) is 50 to 300.
μ-, bulk specific gravity is 0.2 to 0.7. Average particle size is 5
If it is less than 0 μ-, the specific surface area increases, so a large amount of resin is required to bind (bind) the hollow coal ash, and as a result, nonflammability cannot be ensured. Moreover, if the average particle size exceeds 300 pm, the airtightness and surface smoothness of the molded product will be extremely poor. On the other hand, hollow coal ash with a bulk specific gravity of less than 0.2 usually has an extremely low bulk strength, which impairs the mechanical properties of the resulting compact. Moreover, when it exceeds 0.7, the weight reduction of the molded article becomes insufficient. Particularly preferred hollow coal ash has an average particle size of 100 to 200 it m,
It has a bulk specific gravity of 0.3 to 0.5. These hollow coal ash may be treated with a camping agent such as aminosilane or acrylic silane for the purpose of improving interfacial adhesion with the phenolic resin.

The novolac type phenolic resin used in the present invention is
It is an initial condensation product obtained by reacting phenols and aldehydes in the presence of an acid catalyst. means. Phenols refer to phenolic resins, but also include those that induce novolak-type modified phenolic resins, such as cresol and its isomers, xylenol and its isomers, alkylphenols, cashew oil, and bisphenols. At least one selected from these is used. Moreover, aldehydes include formaldehyde, paraformaldehyde, acetaldehyde, furfural, higher aldehydes, and the like. moreover,
Acid catalysts are strong Ml such as oxalic acid, sulfuric acid, and para-toluenesulfonic acid! I, or Ca, Zn, Cd, Pb, Co.

It refers to a metal salt catalyst of an organic acid containing Ni or the like.

The amount of novolac type phenolic resin used in the present invention (
Composition ratio) is 2 to 10% per 100c11” of hollow coal ash.
If the ratio is less than 2g per 10011 of hollow coal ash, the strength of the compact will be low and the mechanical properties as a building material will not be satisfied. Although the physical properties improve, it becomes impossible to ensure nonflammability.

In the present invention, the method of coating hollow coal ash with a novolac type phenolic resin is preferably carried out at a temperature of 150°C to 160°C.
After adding the above-mentioned initial condensate to this hollow coal ash heated to , mixing and stirring (mixing), an aqueous hexamethylenetetramine solution as a hardening agent and calcium stearate as a lubricant are added, or a novolac type phenol containing a hardening agent in advance is added. Examples include a method of using resin powder, dry mixing it with hollow coal ash, adding alcohol, liquid resol, etc., coating and granulating it, and then adding a lubricant. That is, the coating method used in the present invention may be any method as long as it can finally obtain hollow coal ash coated with a novolac type phenolic resin, which undergoes crosslinking reaction and further polymerization by heating. Good too.

The cured side used in the above coating method refers to a compound that can be decomposed by heating and crosslinked with the novolak type phenolic resin initial condensate. Compounds that meet this condition include, for example, hexamethylenetetramine, paraformaldehyde, etc. , solid resol, etc., and preferably hexamethylenetetramine. In addition to the above-mentioned higher fatty acid metal salts such as calcium stearate,
Higher fatty acid amides, higher fatty acid bisamides, polyolefin waxes, paraffin waxes, etc. are preferably used.

In the present invention, the above-mentioned hollow coal ash and Nopola 7-type phenolic resin are essential components, but in addition, additives and fillers commonly used in plastic molding are used, which significantly impairs lightness, mechanical properties, and nonflammability. It can be used as appropriate within the range. As additives, for example, heat stabilizers, ultraviolet absorbers, antioxidants, feeds, dyes, antistatic agents, fungicides, and flame retardants can be used as appropriate.Furthermore, as reinforcing fillers, inorganic powder and granules can be used. , inorganic fibers, etc. can be used.

In the present invention, the method for forming a molded body from the hollow coal ash coated with the novolac type phenolic resin is a method of heating and hardening in a mold, and filling → shaping (heat hardening).
→ Consists of a series of mold release methods 0 For example, heat curing methods include a method in which a preheated mold is filled with coated hollow coal ash and hardened quickly, and a method in which the surface layer of the molded product is hardened and released. Methods that can be adopted include, but are not limited to, a method in which the mold is sufficiently hardened to the inside in a heating furnace after shaping, and a method in which it is heated together with the mold on both sides or one side on a belt conveyor to continuously harden it. 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 mold, etc. are not particularly limited.

(Function) According to the method for producing a phenolic resin composite molded article of the present invention, a large amount of hollow coal ash particles of an inorganic substance is replaced with a very small amount of an organic substance, which is an excellent flame-retardant resin that emits extremely little smoke during combustion. Since it is coated with a novolac-type phenolic resin and then heat-cured and bonded within the mold, the inorganic aggregates are evenly bonded together by the organic material, maximizing the strength of the molded product, which is largely controlled by the physical structure. The molded body formed by the method of the present invention can be used as a building material with excellent flame resistance. It has higher strength than heat-formed products.

Moreover, in the present invention, since hollow coal ash having a nearly spherical shape and a small specific surface area is used as the inorganic aggregate, the amount of resin required for binding the hollow coal ash can be kept to a small amount. In addition, since hollow coal ash has a higher volumetric strength than lightweight aggregates such as calcined pearlite, shirasu balloons, and glass balloons, the molded product is lightweight and has excellent mechanical properties.

(Example) Examples and comparative examples are shown below.

! Approximately 150 to 160
Hollow coal ash heated to ℃ (fi11 manufactured by Nihon Philite Co., Ltd.
ite52/7: Average particle size 75-150J! After stirring and mixing 1 liter (405 g) of Novolak-type phenolic resin (Castol DB-402, manufactured by Dainippon Ink Chemical Industries, Ltd.) for 1 minute,
A solution of 6 g of hexamethylenetetramine dissolved in 20 g of water was added and stirred until the lumps of coal ash were broken up.

Then add calcium stearate Ig and add 30
After stirring for a second, the mixture was taken out from the mixer to obtain hollow coal ash coated with a novolak type phenol resin.

Next, a metal mold (250 x 250 x 12
The molded product was filled into a cup (150 x 100 x 4 m) and heated in a heating furnace at 190°C for 10 minutes, and then the molded product was taken out from the mold.

The bulk specific gravity, bending strength, bending elastic modulus, and nonflammability of the obtained molded body were evaluated. The evaluation was good in all test items. The results are shown in Table-1. In addition, the bending test was performed based on JIS M 7203 by creating an 80 x 10 x 4- test piece from this molded body. In addition, the fire resistance test is based on the Ministry of Construction Publication No. 1 based on the Building Standards Act.
828 (December 28, 1972) for the base material test and surface test, respectively, 40 x 40 x
Test pieces of 50 m and 220 x 220 x 12 mm were prepared.

The weight of the novolac type phenol resin was 70g, and the weight of hexamethylenetetramine and water was 12g and 40g, respectively.
A novolak type phenol resin-coated hollow coal ash was prepared in exactly the same manner as in Example 1 except that g was used, a molded body was obtained, and an evaluation test was conducted. It was good in all test items. The results are also shown in Table-1.

Comparison group top - Also, the weight of novolac type phenolic resin is 105g and 1
5g5 hexamethylenetetramine 18g and 2.6
Novolac type phenol resin-coated hollow coal ash was prepared in exactly the same manner as in Example 1 except that the amounts of g and water were changed to 60 g and 8.6 g, respectively, and each molded article was obtained and an evaluation test was conducted on each. The molded article of Comparative Example 1 containing a large amount of novolac type phenolic resin failed the base material test,
The molded article of Comparative Example 2, which contained a small amount of resin, had low strength.

The results are also shown in Table-1.

1 liter of the hollow coal ash described above and 40 g of powdered thermosetting novolac type phenol resin (containing about 15 wtX hexamethylenetetramine) were mixed at high speed in a mixer,
Using the obtained mixed powder and granular material, a molded body was obtained by the same molding method as in Example 1, and an evaluation test was conducted on the molded body. This molded body had low strength. The results are also shown in Table-1.

Comparison ■Soil-1 Instead of hollow coal ash, fine coal ash (manufactured by Kanden Kako Co., Ltd.: average particle size 5 to 30 μm, bulk specific gravity 1.09) and Shirasu balloon (manufactured by Ijichi Kasei Co., Ltd., Winlite; average particle size 15) were used instead of hollow coal ash.
Coal ash and shirasu balloons coated with novolak type phenolic resin were prepared in exactly the same manner as in Example 1, except that 1 liter of each was used, and each molded body was obtained. An evaluation test was conducted for each of them. The molded product of Comparative Example 4 had a large bulk specific gravity, and the molded product of Comparative Example 5 had low strength. The results are also shown in Table-1.

Furthermore, this molded product can be suitably used as an interior/exterior material for buildings because of its excellent performance in terms of environmental resistance, heat insulation, processability, etc.

Claims (1)

[Claims] (1) Average particle size is 50-300μm, bulk specific gravity is 0.2
A phenolic resin composite molding characterized in that hollow coal ash particles of ~0.7 are coated with a novolak type phenolic resin at a ratio of 2 to 10 g per 100 cm^3, and this is heated and hardened in a mold. How the body is manufactured.