JPS59141454A - Manufacture of flame retardant heat insulating material - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention aims to improve the properties of foamed plastic by casting and curing foamed plastic granules using a mixed binder consisting of a water-soluble silicate (water glass), an inorganic curing agent, and a polyurethane raw material. The present invention relates to a method for producing a flame-retardant heat insulating material that has excellent flame retardancy and fire resistance without impairing heat insulation properties.

Plastic foams are increasingly being used as construction materials due to their excellent heat insulation, water resistance, and anti-condensation properties, but their lack of flame retardancy limits their uses and poses many restrictions from a fire safety standpoint. is recieving. On the other hand, inorganic heat insulating materials such as glass wool have excellent flame retardancy, but have the disadvantage that their heat insulating performance deteriorates due to condensation, and sometimes the condensed water corrodes wood and the like. Although various attempts have been made to improve these drawbacks, the reality is that very few products have been put into practical use due to lack of flame retardancy, water resistance, poor production efficiency, etc.

For example, a method has been proposed in which a water glass-based inorganic binder is mixed with plastic granules and molded, but this method requires a long time to harden and release from the mold, resulting in poor production efficiency and poor water resistance. It has drawbacks such as being impractical for practical use.

The present invention eliminates these drawbacks, and the gist thereof is to prepare a water glass binder comprising a water-soluble silicate, a hardening agent such as zinc oxide, calcium silicate, aluminira-imichi compound 1 asbestos, and a hyoriurethane raw material. The binder was then mixed into the foamed plastic granules and the resulting mixture was cast and cured.

The present invention relates to a method for producing a flame-retardant heat insulating material, which is heat-dried after demolding.

In the present invention, as described above, the water glass binder is composed of an inexpensive water-soluble silicate, an inorganic curing agent, and a polyurethane raw material, so that it hardens quickly at room temperature and can be demolded in a short time. This is because the alkali in the water-soluble silicate acts as a catalyst for the curing of the polyurethane raw material, and the water in the water-soluble silicate reacts with the isocyanate of the polyurethane raw material to promote the curing of the polyurethane raw material. This is because the carbon dioxide gas produced is thought to contribute to the curing of the water glass binder.

Furthermore, when mixing a water glass-based binder with foamed plastic particles, if the binder is mixed so as to be uniformly applied to the individual surfaces of the foamed plastic particles, the flame retardant material of the present invention after casting and curing can be improved. The thermal insulation material has individual foamed plastic particles encapsulated in a cured product of a water gun binder, and can be made to have excellent flame retardancy and water resistance without sacrificing insulation properties. .

Furthermore, in the present invention, the water glass binder can be almost completely cured by heating and drying the defoamed material after casting and curing within a range that does not exceed the softening temperature at which the foamed plastic particles collapse. In combination with this, the flame retardant heat insulating material according to the present invention has even better water resistance.

The foamed plastic granules used in the present invention include foamed granules of polystyrene, polyethylene, polypropylene, polyvinyl chloride, polyurethane, etc., and copolymers of these monomers, among which polystyrene-based and polyvinyl chloride-based granules are used. Preferably.

The size of the foamed granules is not particularly limited, but is between 0.5 and 10.
Those with a dragon diameter are preferably used, and the foaming ratio is 10.
If the foaming ratio used is between 70 and 70 times, the flame retardance will be poor and the object of the present invention will not be met.

Moreover, if it is 10 times or less, the heat insulation properties will be poor.

Also, as a water-soluble silicate, soda water glass is used.

Although potash water glass etc. can be used, soda water glass is preferable in terms of cost, and one with a molar ratio (SiO,/Na20) of 2.1 to 3.5 and a specific gravity of 30 to 59 Baume (20°C) is particularly preferable. .

Hardeners include zinc oxide and calcium silicate.

A mixed curing agent containing at least zinc oxide or calcium silicate selected from aluminum compounds and asbestos as an essential component is used.

Zinc oxide has the effect of increasing the water resistance and hardness of the flame retardant heat insulating material according to the present invention, and calcium silicate has the effect of improving the water resistance and weather resistance.

Aluminum compounds include aluminum hydroxide, alumina,
Hydrated alumina or the like is preferably used and is effective in reducing shrinkage during curing and preventing cracks.

Asbestos has the effect of adjusting the viscosity of the binder, and since asbestos also has the effect of anhydride in the binder, it is effective in improving the strength of the flame-retardant heat insulating material according to the present invention and retaining its shape during combustion.

These curing agents contain, per 100 parts by weight of water-soluble silicate,
Zinc oxide and/or calcium silicate: 5 to 100 parts by weight, aluminum compound: θ to 50 parts by weight, asbestos: 0 to 100 parts by weight
This is because even if an amount exceeding the above-mentioned range is used in a ratio of 50 parts by weight, no significant improvement in the effect can be expected, resulting in a cost disadvantage, and furthermore, the heat insulating effect is destroyed.

Furthermore, if the zinc oxide and/or calcium silicate is less than 5 parts by weight, the water resistance will be poor and the object of the present invention will not be met.Aluminum compounds and asbestos are not essential curing agents for the purpose of the present invention. However, it is preferable to add it in order to improve the various performances mentioned above.

As described above, the polyurethane raw materials of polyol and incyanate have the effect of rapidly curing the mixture of foamed plastic particles and binder after casting, and are used in an amount of 15 to 75 parts by weight per 100 parts by weight of water-soluble silicate.

If it is less than 15 parts by weight, the effect of accelerating curing will be insufficient, and if it is more than 75 parts by weight, the flame retardant effect of the flame-retardant heat insulating material according to the present invention will be lowered, making both of them unsuitable for the present invention.

Isocyanates as raw materials for polyurethane used in the present invention include fatty acids such as tolylene diisocyanate, 44'-diphenylmethane diisocyanate, 1,6-hexamethylene diisocyanate, L5-naphthalene diisocyanate, phenylene diisocyanate, and 4.4r-biphenyl diisocyanate. Any of a group type, an aliphatic type having a cyclic group, an aromatic type, and a biphenyl type can be used.

In addition, as polyols, polyethylene glycol, polypropylene glycol, pentamethylene f IJ =
Polyether type such as y-ru, diglyme, etc. and O at both ends
Polyester-based materials such as H poly(ethylene adipate), poly(propylene adipate), and poly(ethylene succinate) are also used.

Due to the curing effect of incyanate, the amount of isocyanate used is small for 100 parts by weight of water-soluble silicate (10 parts by weight of both are required, and if it is 50 parts by weight or more, the mixing ratio of polyurethane This is because the amount of polyol used is determined by the amount that can react with incyanate, and is used in the range of 5 to 25 parts by weight.

To prepare the binder in the present invention, first, the above curing agent is added to a water-soluble silicate solution, a polyol is further added and mixed, and then incyanate is added to obtain a paste-like binder. This water glass binder is added to and mixed with the foamed plastic particles, and the surfaces of the foamed plastic particles are coated with the binder.

The mixing ratio of foamed plastic granules varies depending on the type of plastic, foaming state, particle size, etc., but 5 to 150 parts by weight of foamed plastic granules per 100 parts by weight of water glass binder, and even 10 to 100 parts by weight. If the amount is less than 0.5 parts by weight, which is the preferable range, the insulation effect will be poor, and if it is more than 150 parts by weight, the surface coating with the binder will be insufficient, resulting in poor flame retardancy.

After the foamed stick granules and the binder are mixed in a mixer, they are molded using a known molding method. For example, when making a plate-like 5-box molded product, the product is poured into a mold by pouring or press-fitting, and left at room temperature for 10 to 20 minutes to harden. In addition, if demolding is to be done in a hurry, heat curing may be performed. The molded product removed from the mold after curing is heated and dried at a temperature below which the foamed plastic particles do not sag. For example, in the case of foamed polystyrene granules, the heating drying conditions are 70°C to 120°C, preferably 8°C.
30 minutes to 5 hours at 0 to 110°C is suitable.

By performing such heat drying, the flame retardant heat insulating material according to the present invention has excellent water resistance.

After heating and drying, cool to room temperature or the like.

The water and gas-based binder according to the present invention includes metal plates such as aluminum plates and steel plates, calcium silicate plates, gypsum plates,
It has extremely good adhesion to inorganic boards such as perlite boards and concrete boards, glass woven fabrics, glass fiber nonwoven fabrics, glass paper, etc., so it is extremely convenient for manufacturing multilayer boards, etc.6.

The flame-retardant heat insulating material obtained by the present invention has excellent flame retardancy and heat insulation properties, and also has excellent water resistance.

Combined with the above-mentioned good adhesive properties, it has the revolutionary feature of being able to be used in many ways as a building material.

The present invention will be further explained below based on Examples.

Example I JI83 Sodium silicate water soluble 'p? i,'(5i02/
Na, O molar ratio 3.0 to 3.2, solid content 40%) 100
g, 10 g of zinc oxide (zinc oxide No. 1), calcium silicate (
A hardening agent consisting of sample, fR) 1 (1, aluminum hydroxide (] Igilite ■H-31) '10.9 and asbestos (chrysotile type, 6D-5) 5 g was added, and to this was added polyether triol (ADEKA). ■G'300) 5g was added and mixed with stirring, and 10.9 g of tolylene diisocyanate (ADEKA ■UP382) was added as an incyanate to prepare a water glass-based binder.150g of this binder and a foaming ratio of 60 20g of foamed polystyrene granules were sufficiently stirred and mixed in a wide-mouthed container, and the mixture was filled into a mold of 25α x 25cTn.
I pressed it to m1 and cured it at room temperature.・1
It became possible to demold the mold in 5 minutes. After demolding, dry in the dryer for 11
The mixture was heated and dried at 0° C. for 1 hour, and then cooled to room temperature to obtain a molded article. Physical properties such as density, compressive strength, water resistance, and thermal conductivity were measured for this molded body. Table 1 shows the results.
Shown below.

Example 2 A molded article was obtained in the same manner as in Example 1 except that calcium silicate was used as a hardening agent. In this example, it was possible to cure and demold in 15 minutes. .

Regarding this molded article, the same physical and characteristic measurements as in Example 1 were conducted. The results are shown in Table 1.

Comparative Example 1 No. 3 sodium silicate aqueous solution 30'OIK used in Example 1
, using the same amounts of the polyol, isocyanate, and expanded polystyrene granules used in Example 1, Example 1
A molded product was obtained by curing at room temperature and demolding in the same manner as above, but no curing agent was used and no heating drying was performed after demolding. In this example, it took 30 minutes to harden and demold.

The same physical properties as in Example 1 were also measured for the molded article of this example. The results are shown in Table 1.

Comparative Example 2 Zinc oxide 20.9 and calcium silicate 209 were added to 300 g of the No. 3 sodium silicate aqueous solution used in Example 1 as a curing agent.
, aluminum hydroxide20. ! 7 and then add expanded polystyrene granules to this water glass binder using 20.
j7 was mixed, cured at room temperature, and demolded in the same manner as in Example 1 to obtain a molded product. In this example, no polyurethane raw material was used, and heating drying after demolding was not performed. In this example, it took 3 hours to harden and demold.

The physical properties of the molded article of this example were also measured in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 3 Using 20 g of the expanded polystyrene granules used in Example 1, a molded article was obtained in the same manner as in Example 1, including curing and demolding at room temperature.

In this example, no water glass binder was used, and no heat drying was performed after demolding. In this example, 2 hours were required for curing, cooling, and demolding.

The physical properties of the molded article of this example were also measured in the same manner as in Example 1. The results are shown in Table 1.

Furthermore, the molded bodies obtained in the Examples and Comparative Examples were tested for flame retardancy in a simple combustion test furnace using an electric furnace.

Assuming that the test piece is 19cm x 19σ x 1-5 (thickness),
The test piece was placed on a support horizontally in a furnace at a temperature of 600° C., and a combustion experiment was conducted for 10 minutes.

As a result, the test piece obtained in Comparative Example 3 began to emit black smoke and burn explosively immediately after being put into the furnace, and was burnt out in 2 minutes without leaving any shape.

On the other hand, the test pieces obtained in Example L2 and Comparative Example L2 started emitting white smoke one minute after being put into the furnace, but the generation of white smoke stopped about 8 minutes in diameter. After the experiment, the surface of the test piece had a honeycomb shape, but it remained in its original shape.

Regarding the flame retardant performance of building materials, even if they burn in the event of a fire, they are required to maintain a shape close to the original without collapsing or causing harmful deformation (for example, JIS
As shown in the flame retardant test of A1321). As seen in the above experiment, the flame retardant heat insulating material according to the present invention was shown to have a high degree of flame retardancy.

Table 1 In the above table, the compressive strength was based on the pressure test of JISA9511 (foam polystyrene insulation material). Thermal conductivity is JIS
Measured by A1412 (flat plate comparison method).

Water resistance is the sample weight before testing. , the same sample at room temperature 23
The water-soluble flame retardancy determined by the following formula is ○, the original shape, as a result of the above experiment, where W is the weight after immersing in water at 105 °C for 24 hours and drying for 2 hours at 105 °C. Those who do not leave behind are blessed with x.

As shown in Table 1, both Examples 1 and 2 have excellent thermal conductivity comparable to that of expanded polystyrene and glass wool, and also have good flame retardancy in a simple combustion test at a high temperature of 600"C as described above. Furthermore, it has excellent water resistance, and is also excellent in productivity, as it can be cured and demolded in a short time.

In Comparative Example 1, the amount of sodium silicate is larger than the amount of polystyrene, so the thermal conductivity is high, making it unsuitable as a general heat insulating material (thermal conductivity of 0.05 Kcal/m-h-C or less) and not being water resistant. The properties were also very poor, and furthermore, the curing and demolding required more time than in Example L2, resulting in poor production efficiency.

In Comparative Example 2, since polyurethane/raw material was not used, it took too much time to harden and demold, resulting in extremely low production efficiency, and the product also had poor water resistance because it was not heated and dried after demolding. Further, as in Comparative Example 1, the amount of sodium silicate is larger than the amount of polystyrene, so the heat insulation properties are also extremely poor.

In Comparative Example 3, it took too long to harden and demold, resulting in poor production efficiency, and even though it was molded from self-extinguishing grade expanded polystyrene granules, it burned out in the simple combustion test. K, which has very poor flame retardancy and poor compressive strength, is used as a lumber 13 material.
has limited use.

Patent applicant: Zeon Corporation

Claims (1)

[Claims] 1. In the foamed plastic granules, (a) a water-soluble silicate and 100 parts by weight of the silicate, (1) 5 to 100 parts by weight of the following hardening agent zinc oxide and/or calcium silicate. Aluminum compound 0-507 Asbestos 0-50 and (C) polyurethane raw material for polyol and isocyanate
1. A method for producing a flame-retardant heat insulating material, which comprises adding and mixing 15 to 75 parts by weight of a binder, casting and curing the resulting mixture, removing the mold, and then heating and drying.