JPS63460B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention has excellent flame retardancy and also
The present invention relates to a flame-retardant putty-like composition that exhibits a high degree of airtightness when used to fill voids in cable through-holes in fire walls, joints in building interior materials, etc. In recent years, tragic cases of building fires caused by smoke generation and fire spread from various types of synthetic polymer interior materials, rubber and plastic electric wires and cables have been frequently reported. For this reason, fire prevention measures have recently been emphasized, with laws and regulations regarding fire prevention being strengthened.
Technological development related to fire prevention and fire resistance has become a pressing issue among those involved. Today, fireproofing and flame-retardant materials are used in the interior materials of buildings, ships, vehicles, etc., and fire prevention measures are being taken such as installing fire walls to protect emergency equipment. When exposed to high temperatures, they may deform or char, creating gaps in the joints that allow flames to enter and spread the fire. Smoke and flames may leak, spreading fire to electric wires and cables and causing damage to emergency equipment. By the way, various flame-retardant putty-like compositions have been proposed as fillers that provide fire-retardant properties to such places, but although they all have good flame-retardant properties, they do not stand up well under fire. After being exposed to high temperatures, it becomes brittle and easily collapses, resulting in a significant lack of airtightness, which ultimately prevents it from being a completely fireproof structure. A high degree of airtightness after being exposed to the high temperature of a fire is extremely important in preventing the spread of fire, and a flame-retardant composition that satisfies such performance has been desired. The present invention was made based on this finding, and the amount of B to 100 that exceeds 200 to 700 parts by weight of alumina hydrate and 15 parts by weight of heat-resistant fibers per 100 parts by weight of chloroprene polymer that is liquid at room temperature. By making the putty-like composition into a putty-like composition of parts by weight, a flame-retardant putty-like composition was completed which has particularly excellent flame retardancy and also has extremely excellent airtight performance at room temperature and at high temperatures under fire. The putty-like composition of the present invention has moderate plasticity at room temperature,
It is adhesive and can be easily filled not only through holes in fire walls for electric wires and cables, but also at joints in interior materials of buildings, etc. In addition, it has excellent airtightness at room temperature, which prevents the spread of smoke in the event of a fire, and because it does not harden over a long period of time, it is not necessary to rewire electric wires and cables or replace interior materials. At this time, the putty-like composition can be disassembled, removed, and reused freely. Furthermore, under the high temperature of fire, the flame retardance of liquid chloroprene itself,
The non-combustibility of alumina hydrate and the synergistic effect with heat-resistant fibers provide an extremely high degree of flame retardancy, and even when exposed to high temperatures under fire, it does not soften, drip, or become brittle like conventional compositions. Without a doubt,
Moreover, even if it burns, it forms a strong and dense ash residue layer, exhibiting advanced airtightness that strongly prevents the spread of fire. Among the above-mentioned performances of the flame-retardant putty-like composition of the present invention, the above-mentioned non-dripping property and the ability to form a dense ashing residue layer with excellent mechanical strength upon combustion are the same as those found in conventional compositions. This is a remarkable effect of the present invention. The chloroprene polymer that is liquid at room temperature used in the present invention is a low molecular weight chloroprene homopolymer or chloroprene copolymer with a viscosity in the range of 5,000 to 30,000 C.PS at room temperature (25°C), and preferably has a molecular weight of Those having a functional group at the end are used. The above-mentioned chloroprene-based copolymer includes monomers copolymerizable with chloroprene, such as styrene,
Various copolymers with vinyl compounds such as methacrylic acid, methyl methacrylate, and acrylonitrile, conjugated dienes such as 1,3-butadiene, isoprene, and 2,3-dichloro-1,3-butadiene, and chloroprene-sulfur copolymers. As the functional group, those having a thiol group, a hydroxyl group, a carboxyl group, an alkylzantate group, an active halogen group, or a carbon-carbon unsaturated bond are used. Among the above-mentioned liquid chloroprene polymers used in the present invention, chloroprene homopolymers or chloroprene copolymers having an alkylzantate group at the end are preferred in order to obtain good flame retardancy and high airtightness. More preferred is a mixture of a chloroprene homopolymer or chloroprene copolymer having an alkylzantate group at the end and a chloroprene homopolymer or chloroprene copolymer having a hydroxyl group at the end. Next, the alumina hydrate used in the present invention is represented by the general formula Al ₂ O ₃ · nH ₂ O,
The number n is 0.5 to 6, for example, the chemical formula Al ₂ O ₃ 1/2H ₂ O,
Any material that decomposes endothermically at high temperatures, such as Al ₂ O _{3 .H 2} O, Al ₂ O ₃ .2H ₂ O, Al ₂ O ₃ .3H ₂ O, etc., can be used as appropriate. 2 to 4, for example, those represented by the chemical formula Al ₂ O ₃ .3H ₂ O are desirable. Upon decomposition, such alumina hydrate absorbs a portion of the combustion heat, lowers the temperature of the putty-like composition exposed to the flame, and dilutes combustible gases contained in the flame with decomposed water vapor. It has flame retardant properties such as Furthermore, the putty-like composition forms a strong and dense ashing residue layer even when exposed to high temperatures in a fire.
It has the function of creating a highly airtight state in construction areas such as electric wire/cable through holes. The alumina hydrate used in the present invention preferably has different particle sizes in order to form a strong and dense ashing residue layer under the high temperature of a fire.
A mixture of particles having an average particle size of 10 to 100 μm and particles less than 10 μm is preferable. Furthermore, the blending ratio is preferably 20 to 300 parts by weight of particles less than 10 μm per 100 parts by weight of particles with an average particle size of 10 to 100 μm. Further, the blending ratio of the alumina hydrate to the liquid chloroprene polymer is 200 to 700 parts by weight, preferably 250 to 450 parts by weight per 100 parts by weight of the liquid chloroprene polymer. If it is less than 200 parts by weight, the fluidity of the putty-like composition will be significantly increased, and after application, it will tend to fall off at room temperature, and the flame retardance will also decrease, which is not preferable. If the amount exceeds 700 parts by weight, the kneading processability during packaging of the putty-like composition will be poor and it will not be possible to form a putty-like composition. Furthermore, the heat-resistant fiber used in the present invention prevents the putty-like composition from deforming due to thermal expansion of electric wire covering materials or building interior materials under high temperatures of fire, and also works together with alumina hydrate. In order to provide this function to the putty-like composition, the blending ratio of the heat-resistant fibers to the liquid chloroprene polymer should be set at a higher level. A high ratio is desirable, and an amount of at least more than 15 parts by weight to less than 100 parts by weight, more preferably from 20 to 60 parts by weight per 100 parts by weight of the liquid chloroprene polymer. If it is less than 15 parts by weight, it is not preferable because it impairs the crack prevention function of the putty-like composition and the ability to maintain the formation of an ash layer under the high temperature of a fire. If the amount exceeds 100 parts by weight, the kneading processability during production of the putty-like composition will be significantly impaired, and the composition will not be putty-like and will not exhibit the required functions. As the heat-resistant fibers, inorganic fibers, organic fibers, or mixtures thereof are used. As the inorganic fibers, glass fibers, asbestos fibers, carbon fibers, etc. alone or in mixtures thereof are used, and as the organic fibers, phenolic fibers, polyimide fibers, polyamide-imide fibers, etc. are used, but inorganic fibers are preferably used. More preferably, among the inorganic fibers, a mixture of glass fiber and asbestos fiber is preferable, and 100 μm or less of glass fiber with a length of 2 to 15 mm is used per 100 parts by weight of glass fiber of 100 μm or less and a length of 2 to 15 mm.
10 to 300 asbestos fibers with a length of 2 to 15 mm or less
Parts by weight are best. In addition, when carrying out the present invention, fillers, carbon black, anti-aging agents, pigments, inorganic fillers, surface improvers,
If the total amount of plasticizers, flame retardants, stabilizers, etc. and anti-sag agents, etc. that are usually added to putty-like compositions is 50 parts by weight or less per 100 parts by weight of the putty-like composition of the present invention, It may be blended into the putty-like composition of the present invention. The putty-like composition of the present invention can be manufactured by mixing it in an ordinary kneader, and the resulting mixture can be applied to through-holes in fire walls for electric wires and cables, joints in building interior materials, etc. It can be easily filled by the method. The effects of the flame-retardant putty-like composition of the present invention will be shown in more detail by Examples below. Examples 1 to 10, Comparative Examples 1 to 4 The compositions of Examples 1 to 10 and Comparative Examples 1 to 4 shown in Table 1 were kneaded and produced in an experimental kneader with a capacity of 2, and the tests described below for each composition were carried out. According to the method and evaluation criteria, kneading workability, airtightness, flame retardance, heat deformation resistance, fire resistance, and softness characteristics over time were evaluated. The results are shown in Table 2. The test methods and evaluation criteria for each of the above characteristics are as follows. (Kneading processability) Specified amounts of each composition were added to an experimental kneader with a capacity of 2 and 2 stirring blades, and stirred for 40 minutes at room temperature to 80°C. It is observed and judged in three stages: excellent, good, and poor. (Airtightness) One end of an iron pipe with an inner diameter of 300 mm and a length of 600 mm was filled with each composition to a thickness of 100 mm, the surface of each composition was exposed to atmospheric pressure in an atmosphere of 80°C, and the other end of the pipe was filled with each composition to a thickness of 100 mm. Air pressure of 0.8Kg/cm ² cage pressure on the side 5
If the amount of air leaking from the filling composition during that time is 5/min or less, it is considered to be a pass. (Flame retardancy) Determine the oxygen index of each composition according to JISK7201,
Flame retardancy was indicated based on the following criteria. ●Oxygen index 80 or more...Excellent●Oxygen index 60 or more but less than 80...Good●Oxygen index less than 60...Unsuitable (heat deformation resistance) Each composition is molded into a columnar body of 3 cm x 3 cm x 7 cm, and they are held upright. In the oven at 250℃ under
After holding for 30 minutes, it was taken out, and the heat deformation resistance was displayed according to the following judgment. ●Deformation rate in the height direction of the columnar body is less than 5%...Excellent●Deformation rate in the height direction of the columnar body is 5% or more and less than 10%
...Good ● The deformation rate of the columnar body in the height direction is 10% or more, or those that fall during heating or those that cause cracks.
...Not possible (fireproof) Each composition was formed into a cube of 3 cm x 3 cm x 3 cm, and heated in an electric furnace at 1000°C for 3 hours.
After being completely incinerated, it was taken out and allowed to cool.The state of the incinerated residue layer was observed by appearance and touch, and the fire resistance was indicated based on the following criteria. -Things that do not crumble even if the ashing residue layer is strongly pressed with your fingertips.
...Excellent: The ashing residue layer crumbles slightly when pressed strongly with the fingertip. ...Good: The ashing residue layer easily disintegrates even when lightly touched with the fingertip. ....Not acceptable (softness characteristics over time). Fill a metal container with a depth of 50 mm and an inner diameter of 70 mm so that the surface is smooth, and heat it at 70℃ for 14 days.
The softness at °C was measured according to JISA5752, the rate of change was determined based on the softness before heating, and the softness characteristics over time were expressed using the following judgment method. ●Softness change rate less than 20%...Excellent●Softness change rate 20% or more and less than 50%...Good●Softness change rate 50% or more...Not acceptable

【table】

[Table] (Note) *Items that cannot be measured As is clear from the examples above, the flame retardant putty-like composition of the present invention has good kneading processability during manufacturing and has a moderate level of kneading processability during construction. It has softness,
It does not harden for a long time at room temperature and is extremely easy to use.
In addition, it is an excellent flame-retardant putty-like composition that has not only airtightness at room temperature but also strong and dense airtightness even when exposed to high temperatures under fire, so it is extremely useful.

Claims (1)

[Claims] 1 Consisting of 200 to 700 parts by weight of alumina hydrate and more than 15 to 100 parts by weight of heat-resistant fiber per 100 parts by weight of chloroprene polymer that is liquid at room temperature,
And, the average particle size of the alumina hydrate is 10
The average particle size per 100 parts by weight of ~100μm is
1. A flame-retardant putty-like composition comprising 10 to 500 parts by weight of particles less than 10 μm.