JPS63264645A - Inorganic substance-containing chlorinated vinyl chloride resin foam and its production - Google Patents

Abstract

PURPOSE:To obtain a foam low in a calorific value and smoke generation upon burning and high in dimensional retentivity upon outdoor exposure, by packing a mixture of a chlorinated vinyl chloride resin, an inorganic substance a decomposable blowing agent and a solvent in a sealed mold and heating this mixture under a pressure. CONSTITUTION:An expandable composition formed by kneading a chlorinated vinyl chloride resin (CPVC) with an inorganic substance, a decomposable blowing agent and a solvent is packed in a sealable mold and heated under a pressure to effect the melting and gelation of the chlorinated vinyl chloride resin and the decomposition of the decomposable blowing agent. The mold is opened at a temperature suitable for expansion to expand the mixture. As said solvent used, one having an ability of allowing CPVC to gel is used. Namely, by forming a uniform gel phase from CPVC and the solvent and embedding the inorganic substance in this gel phase, it is made possible to add a large amount of the inorganic substance to the resin. Especially, even when the composition contains an inorganic fibrous material which otherwise interferes with expansion, it is possible to produce a foam having a high expansion ratio and a high closed cell content.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a chlorinated vinyl chloride resin (hereinafter referred to as CPVC) foam containing an inorganic substance and a method for producing the same.

More specifically, the present invention provides CPVC that has low heat generation and smoke generation during combustion, and has excellent heat resistance and flame retardancy.
In addition to retaining its original characteristics, it also has a high dimensional retention rate when exposed to high temperatures (for example, left in an atmosphere of 200°C for 1 hour), making it suitable for insulation materials, building materials, chemical equipment parts, electrical parts, vehicle parts, etc. The present invention relates to a CPVC foam containing an inorganic material that can be suitably used as an inorganic material, and a method for producing the same.

[Prior art and its problems] CPVC contains chlorine as a constituent element, so it is wood-like and flame-retardant, and has the characteristic of producing a small amount of heat and smoke even when forced to burn.

Therefore, CPVC foam is expected to be used as a heat insulating material with higher fire prevention performance than before.

However, since CPVC used as the base resin of CPVC foam is a thermoplastic resin, the CPVC
When VC foam is heated to, for example, 200°C, it shrinks rapidly and becomes unusable, and when placed in a forced combustion atmosphere, it shrinks to the point where it no longer retains its shape. .

In addition, conventional methods for producing CPVC foam include, for example! ``I'+ A method of impregnating CPVC powder or CPVC pellets with an evaporative foaming agent and extruding foaming using an extruder,
(1) A method of impregnating CPVC pellets with an evaporative foaming agent, enclosing the pellets in a preheated mold, and performing foam molding. Method of extrusion foaming after kneading, (=)C
There is a method of mixing PVC with a decomposable foaming agent and extruding it into foam (however, the resulting product is a low-foamed product with a foaming ratio of about 3 times).

However, in the conventional method for manufacturing CPVC foam, even if a large amount of inorganic material is included, the cell membrane is damaged during foaming and becomes open cells, making it difficult to produce a good foam.

In recent years, much research has been conducted on the manufacturing method of CPVC foam, for example, CPV, which is characterized by adding alcohol to CPVC and foaming it by heating.
A method for producing C foam (see Japanese Patent Publication No. 53-27300) and a method for producing a CPVC foam characterized by incorporating a specific solvent into CPVC and foaming it by heating (Japanese Patent Publication No. 5G-25340) ) etc. are known.

However, these foam manufacturing methods have not been able to produce CPVC foams with the required dimensional retention.

Therefore, the present inventors have conducted extensive research to solve the problems of the prior art described above, and have found that when a large amount of inorganic material is contained in the prior art, the cell membrane may be damaged during foaming, or the resulting CPVC It was thought that the foam would become brittle, but
The present invention has developed a CPVC foam that does not have the above-mentioned problems even when it contains a large amount of inorganic material, which is surprising considering the conventional technology, and has an appropriate dimensional retention due to the inclusion of a large amount of inorganic material, and a method for producing the same. This finding led to the completion of the present invention.

[Means for Solving the Problems] Firstly, the present invention provides a CPVC foam that has a dimensional retention rate of 70% or more when heated at 200°C for 1 hour and an expansion ratio of 5 times or more. Regarding.

The inorganic-containing CPVC foam of the present invention comprises cpvc
It is obtained by incorporating inorganic substances into foam and forming it into a foam.
The dimensional retention rate when exposed to high temperatures is greatly influenced by the type of inorganic material and its size.

Since it is not always easy to easily and reproducibly evaluate shrinkage behavior through combustion tests, we conducted extensive research and measured dimensional retention after heating for 1 hour at a temperature exceeding the softening point of CPVC (200°C). It was found that the shrinkage behavior during combustion can be evaluated by doing this.

When heating the CPVC foam containing various inorganic substances under these conditions and evaluating the dimensional retention rate, it was found that the dimensional retention rate depends on the type of inorganic substance contained and the amount of inorganic substance contained in the unit volume of the foam. I found that it is affected.

As a result, the dimensional retention rate of the CPVC foam containing no inorganic material was approximately 40% under the above conditions, and the shrinkage was large. Since the amount of inorganic material packed into the unit volume of the body is appropriately selected and used, the dimensional retention rate is as high as 70% or more, and the heat shrinkage is extremely small. In other words, the CPVC foam of the present invention has a small calorific value and a small amount of smoke,
Furthermore, dimensional shrinkage upon heating at temperatures exceeding the softening point of CPVC (200° C.) is extremely small.

Secondly, the present invention is directed to a CPVC containing a phosphoric acid ester and an inorganic substance and having a chlorine content of approximately 68% or more.
The present invention relates to a composition foam consisting of.

The characteristics of CPVC that the calorific value and smoke emission are small are more pronounced as the chlorine content is higher. Furthermore, CPVC with a high chlorine content is easy to foam, depending on the manufacturing method.

Although CPVC has such characteristics, a foam made of a composition of CPVC with a chlorine content of approximately 68% by weight or more than 96% and an inorganic substance is forcibly burned (for example, according to JIS
If the foam is subjected to a surface test (according to A 1321), the resin portion will ash, making it difficult to maintain the shape of the foam, and in severe cases, the foam may collapse.

Such properties when using CPVC with a chlorine content of approximately 68% by weight or more are not preferable for use as a heat insulating material with high fire prevention performance.

As a result of intensive studies by the present inventors, it has been found that by adding a phosphoric acid ester to a composition consisting of CPVC with a chlorine content of approximately 68% by weight or more and an inorganic substance, it is possible to forcibly burn the foam. A remarkable effect was found in that it could prevent the ashing phenomenon of wood. In other words, since CPVC has a high chlorine content, its calorific value and smoke emission are particularly small, and since it contains a large amount of inorganic material, it is extremely difficult to shrink when heated at temperatures exceeding the softening point of CPVC (200°C).
Furthermore, we have discovered that the resin part does not turn into ash even if it is forced to burn, and the foam maintains its shape.

Thirdly, the present invention provides for the first time a method for producing a CPVC foam that has excellent fireproof performance by containing a large amount of inorganic substances as described above.

As an example of the method of the present invention, a foaming composition obtained by kneading a CPVC1 inorganic substance, a decomposable foaming agent, and a solvent is filled into a sealable mold and heated under uniform pressure to cause dissolution and gelation of CPVC and decomposition foaming. After the agent has decomposed, the mold is opened at the appropriate foaming temperature and foamed at the same time.
This makes it possible to produce a CPVC foam containing a large amount of inorganic matter.

Here, the suitable foaming temperature is defined as the temperature at which the resin film is expanded to a practically meaningful foaming ratio (varies depending on the application, but for example, when used as a building insulation material, it is approximately 5 times or more) due to the foaming power of the foaming agent. It takes a different value each time depending on the type of CPVC, the type and amount of inorganic material, the type and amount of decomposable blowing agent, the type and amount of solvent, and the shape and size of the foam.

The key point of the present invention is to use a solvent that has the ability to gel CPVC.

That is, CPVC and the solvent form a uniform gel phase, and by embedding the inorganic substance in this gel phase, it is possible to add a large amount of the inorganic substance.

In particular, even when containing inorganic fibrous materials that inhibit foaming, it is possible to produce foams with a high expansion ratio and a large closed cell ratio.

Although the function of the solvent is not necessarily clear, at least by forming a uniform gel phase, it increases the volume of the resin part and reduces the viscosity of the resin part, compared to the case where no solvent is present, so that the resin part becomes inorganic. This is thought to have the effect of improving the degree of embedding. It is also believed that by wetting the surface of the inorganic material with a solvent, air adhering to the surface of the inorganic material is removed, thereby making the adhesion between the surface of the inorganic material and the resin part stronger.

Furthermore, the solvent dissolves foaming gases such as nitrogen and carbon dioxide generated by the decomposition of the decomposable blowing agent in the closed mold.
It is thought that it plays a role in stably retaining these foaming gases while the mold is closed.

In addition to the above, due to the coexistence of a solvent, the molding temperature is significantly lower than that of normal CPVC, and CPVC
This method has the advantage of almost eliminating the risk of resin decomposition and deterioration problems that are inherent in VC processing.

In this way it became possible to produce CPVC foams containing a large amount of minerals, or the solvent simultaneously
It tends to enhance the heating dimension retention performance of VC foam. It is believed that this reduces the viscosity of the CPVC composition during foaming, thereby reducing shrinkage due to residual stress and strain in the foam. In addition, since the volume of the resin part increases with the solvent, when trying to achieve a certain expansion ratio, the volume increase during foaming becomes smaller, which reduces shrinkage due to residual stress and residual strain in the foam. It is thought that It is also believed that due to the presence of the solvent, the residual stress and strain during foaming are relaxed during the layer time after foaming.

[Examples] CPVC as used herein refers not only to resins obtained by chlorinating vinyl chloride resins, but also blending resins that are compatible with this resin, such as vinyl chloride resins, vinyl chloride-vinyl acetate copolymers, A mixture with at least one of chlorinated polyethylene, vinyl chloride-vinylidene chloride copolymer, ethylene-vinyl acetate copolymer, methacrylate-acrylate copolymer, thermoplastic polyurethane, acrylonitrile-butadiene copolymer, etc. And,
The amount of blending resin in the mixture is 50% by weight or less.

As the vinyl chloride resin to be chlorinated, in addition to vinyl chloride resins, copolymers containing 50% by weight or more of vinyl chloride can also be used.

Any conventionally known method may be used for the chlorination, and for example, a photochlorination method under ultraviolet irradiation can be preferably applied.

There is no particular limitation on the average degree of polymerization of CPVC, but 300
It is preferably 5,000 to 5,000, more preferably 5,000 to 4,000, particularly preferably 1,000 to 3,000. In addition, if the degree of polymerization is less than 300, various physical properties of the resulting foam may deteriorate.

As the degree of polymerization increases, the physical properties of the foam improve, but foams with a degree of polymerization exceeding 5,000 are difficult to produce industrially. There is no particular limitation on the chlorine content of the CPVC, but if phosphate ester is not used in combination, it is preferably 57% by weight or more, preferably <80 to 75% by weight, and 63 to G9ffiR%. More preferably, it is present, and particularly preferably from 63 to 67% by weight. When the CPVCEil in the foam is constant, the higher the chlorine content, the lower the amount of heat generated during combustion and the amount of smoke produced. Therefore, the chlorine content is preferably 57% by weight or more. Conversely, if the calorific value and smoke emission during combustion are kept below a certain value, the CPV (j;k) in the foam can be increased as the chlorine content km increases.
From the point of view of improving the physical properties of the foam, the chlorine content was increased to 5.
7 weight is preferably 96 or more. On the other hand, those with a chlorine content exceeding 75% by weight are difficult to produce industrially. Furthermore, if the chlorine content is 68% by weight or more, the CPVC is not only carbonized but also tends to ash when burned. Therefore, in this case, it is preferable to incorporate a phosphoric acid ester to prevent ashing. When a phosphoric acid ester is blended, the chlorine content of CPVC is preferably 68 to 75% by weight, preferably 68 to 72% by weight, but the present invention is not limited to such a chlorine content. . In addition, the particle size of CPVC is within the commonly used range,
For example, it is preferable that the amount of particles that do not pass through the 42 mesh is 10% by weight or less, but the present invention is not limited to such a particle size.

The inorganic substance used in the present invention is used not only as a nucleating agent but also to improve the properties such as dimensional retention of the resulting foam. Inorganic fibrous materials have better dimensional retention when exposed to high temperatures. Since the inorganic fibrous materials are entangled with each other in the foam to form a network, it is presumed to have excellent shape stability. Although the effect of inorganic granular materials is smaller than that of inorganic fibrous materials, they have the effect of maintaining dimensions and also have the effect of making cells uniform and fine. Examples of inorganic fibrous materials include asbestos with an average fiber length of about I Hm ~5'Omm, 0.0
Glass fibers, rock wool, ceramic fibers, etc. of about 5 to 10 ma+ are suitable, and inorganic granules include talc, calcium carbonate, and calcium carbonate with an average particle size of about 0.01 to 3004 m.
antimony trioxide, aluminum hydroxide, ferric oxide,
Magnesium hydroxide, zinc oxide, mica, bentonite,
Clay, shirasu balloon (hollow body), etc. are suitable, but the present invention is not limited to these, and other materials can also be used.

Among the inorganic fibrous materials, the heat resistance of the fiber itself is high, with a melting point of about 1520°C, and the fiber diameter is 0.1 inch to 0.03 inch.
Asbestos is one of the most preferable fibrous materials in terms of its fineness (m) and price. Furthermore, the inventors have not seen or heard any reports that glass fibers, rock wool, and ceramic fibers cause health problems such as lung cancer, as has been reported for asbestos, and in addition, industrially uniform fiber length It can be cited as one of the preferred fibrous materials because it can be easily produced with the following qualities.

However, perhaps due to the large fiber diameter, CPV with good inorganic content
c) The amount of solvent used to obtain the foam tends to be larger than that of asbestos. Among the two, it is cheaper and has higher heat resistance [Softening point of glass fiber (E-glass general products): approximately 840°C1
Rock wool has a melting point of about 1,300 degrees Celsius, and its fiber diameter is small [fiber diameter of glass fiber (E-glass common products): 10 to 13 meters, fiber diameter of rock wool = 4 to 6 m]. preferable.

Among the inorganic particulate materials, it is preferable to use antimony trioxide or phosphoric acid ester in combination because they exhibit a mutual effect of increasing the effect of preventing the ashing phenomenon during forced combustion and decreasing the calorific value.

The above-mentioned inorganic substances may be used alone or in combination of two or more. The amount of the inorganic substance to be blended is determined by considering the amount to be contained in the foam, expansion ratio, cell diameter, cell uniformity, cost, etc., but is usually 5 to 1000 parts by weight per 100 parts by weight of CPVC. Preferably 10 to 11,000 ff1 part, more preferably 30 to 500 parts by weight, <50 to 500 parts by weight,
Most preferably it is 80 to 500 heavy engineering parts.

The dimensional retention rate when heated at 200℃ for 1 hour was 7.
The amount of the inorganic substance to be added to 0% or more varies depending on the type of the inorganic substance. A small amount of inorganic fibrous material exhibits a large dimensional retention effect, and the longer the fiber length, the greater the effect. For example, the Canadian Quebec standard rating is 7M.
When asbestos is used alone, it exhibits an excellent dimensional retention effect by blending 0.01 g or more into 1 cff13 of the foam. In particular, it is preferable that 0.01 g or more of asbestos or rock wool be contained in the foam 1 am3.

Since the inorganic particulate material needs to be blended in a larger amount than the inorganic fibrous material, it is preferable to use it in combination with the inorganic fibrous material. Note that when only inorganic particles such as talc, calcium carbonate, or a mixture thereof are used, foamed IC
It is necessary to mold 0.06g or more in 113.

The foam of the present invention may have any density as long as it can be manufactured; however, if the expansion ratio is 200 times or more, it is difficult to manufacture a normal foam. In addition, when using it as a thermal insulation shrine for buildings, physical properties such as thermal conductivity and appropriate values are required.

In order to maintain stability, it is preferable that the foam has an expansion ratio of 5 times or more. When considering the amount of heat generated during combustion, the amount of smoke produced, and economic efficiency, it is preferable to use a foam with a higher expansion ratio, and the expansion ratio is preferably 20 times or more, more preferably 30 times or more, and most preferably It is more than 60 times. It should be noted that according to the method of the present invention, it is possible to obtain a CPVC foam having a high expansion ratio and containing not only inorganic particulates but also inorganic fibrous materials that generally inhibit foaming.

The thickness of the foam of the present invention may be any thickness as long as it can be manufactured, but it is usually 5 to 500 mm, preferably 50 to 500 mm.
It is about 200+nm. In addition, by performing secondary processing such as cutting this foam with a cutting machine, 2II
It is possible to arbitrarily produce products having a thickness of about lff1 or more up to about the original foam thickness.

The phosphate ester used in the present invention is, for example, an orthophosphoric ester such as tributyl phosphate, trischloroethyl phosphate, or tricresyl phosphate, or a phosphorous ester such as triphenyl phosphite, but is not limited to these. It's not something you can do.

In the present invention, it is particularly preferable to use orthophosphoric acid ester, which has a remarkable ashing prevention effect.

Phosphorus, along with halogen atoms, is known as a flame retardant element, and the present inventors have found that it has a remarkable ashing prevention effect when used as a phosphoric acid ester in CPVC foam.

In the present invention, it is preferable to use a phosphoric acid ester containing 7% by weight or more of phosphorus. Lin's confession is 7 weight 96
If it is less than that, the effect of preventing ashing phenomenon during forced decombustion is likely to be insufficient.

Phosphate esters may contain halogen atoms such as chlorine atoms and bromine atoms in addition to phosphorus, and when halogen atoms are contained, the flame retardant effect of the halogen atoms is added. More preferred. The halogen content of the phosphoric acid ester containing a halogen atom is preferably in the range of 20 to 50% by weight when the halogen atom is a chlorine atom.

Among the above-mentioned phosphoric acid esters, trischloroethyl phosphate is preferred because it has a particularly remarkable effect of preventing the ashing phenomenon during forced combustion.

The amount of phosphoric acid ester used is preferably 5 to 50 parts by weight, more preferably 5 parts by weight, based on CPVC too parts by weight.
~30 parts by weight. If the amount is less than 5 parts by weight, the effect of preventing the ashing phenomenon during forced combustion is likely to be insufficient, and if it exceeds 50 parts by weight, there is concern that the physical properties of the foam, such as strength, may deteriorate.

Examples of decomposable blowing agents used in the present invention include azobisisobutyronitrile, azodicarbonamide, diazoaminobenzene, N,N-dinitrosopentamethylenetetramine, p-toluenesulfonyl hydrazide, sodium bicarbonate, and azide compounds. can be given.

The amount of decomposable blowing agent used varies depending on the desired expansion ratio and type of blowing agent, but is usually CPVCto.

0.1 to 100 parts by weight, preferably 10 parts by weight
~40 parts by weight. It may also be used in combination with a foaming aid.

As the solvent used in the present invention, any solvent can be used as long as it has the ability to gel CPVC.

For example, aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene; chlorobenzene, 1,2.
Halogenated hydrocarbons such as 4-trichlorobenzene and carbon tetrachloride; Compounds containing 011 groups and ether groups such as butyl cellosolve; Ketones such as di-isobutyl ketone, methyl isobutyl ketone, and cyclohexanone; Normal amyl acetate, isoamyl formate, and normal acetate Examples include esters such as butyl; carbonic acid derivatives such as diethyl carbonate; phosphorus compounds such as tricresyl phosphate; these may be used alone or in combination of two or more.

The amount of solvent used is 60 to 100 parts by weight of CPVC.
The amount is 1000 parts by weight, preferably 100 to 500 parts by weight, and more preferably 150 to 500 parts by weight.

Generally, as the amount of inorganic material increases, a larger amount of solvent is required, and the larger the amount of solvent, the stronger the dimensional retention of the foam when heated. Further, a larger amount of solvent is required when using an inorganic fibrous material than an inorganic granular material. On the other hand, if the amount of solvent is too large, the foaming temperature will become low, and even if foaming is carried out at an appropriate foaming temperature, the closed cell ratio may decrease or a foam with a satisfactory shape may not be obtained.

As the stabilizer that can be used in the present invention, any stabilizer can be used as long as it has the ability to inhibit the decomposition and deterioration of CPVC, including complex salt stabilizers such as dibasic lead stearate, butyltin laurate, etc. system, butyltin maleate system,
Organotin stabilizers such as dibutyltin laurate malate are particularly suitable because they have excellent stabilizing properties.

In the present invention, in addition to the above, plasticizers such as dioctyl phthalate; ultramarine, watching red,
Pigments such as titanium oxide and carbon black; antistatic agents such as tertiary amines and alkyl sulfonates;
It goes without saying that substances commonly used as additives for plastics, such as metal soaps such as lead stearate and lubricants such as fatty acids such as stearic acid, may be used as necessary.

Next, the present invention will be explained in detail.

Predetermined amounts of each raw material are blended and thoroughly kneaded using a ribbon blender, double-arm kneader 1 pressure kneader, Banbury mixer, etc., to prepare a foamable composition.

The prepared foamable composition is filled into a closed mold made of, for example, an aluminum alloy, and the mold is set in a hydraulically driven heating press to heat the composition under pressure.

Pressure and heating conditions vary depending on the constituent components of the composition, but it is necessary to substantially complete the melting and gelation of CPVC and the decomposition of the decomposable foaming agent, and the appropriate temperature depending on the foamable composition is required. , time and pressure are selected. Thereafter, the temperature of the pressure heating plate of the press is lowered to i1R degree, which is suitable for foaming, using a cooling medium such as water while the mold is kept pressurized.

The suitable temperature for foaming varies depending on the composition of the foamable composition or the shape and dimensions of the mold, or is usually lower than the pressure and heating temperature, so that foaming gas does not escape due to tearing of the cell curtain during foaming. The temperature that gives viscoelasticity to such a CPVC layer is, for example, about 0 to 100°C. When the mold contents reach a suitable temperature for foaming, the mold is opened and the mold contents are released to atmospheric pressure.

Since the mold contents contain the foaming power of the foaming agent and the viscoelasticity of the CPVC phase is suitable for foaming, the mold contents expand and foaming is completed in a short time.

According to the production method of the present invention, a desired foam can be easily produced by secondary foaming alone, but the primary foam obtained by the production method of the present invention may be subjected to secondary heating as an auxiliary.

Since the used solvent remains in the foamed product immediately after foaming, the remaining solvent is volatilized and removed by leaving it for an appropriate time at an appropriate temperature depending on the solvent.

The foam obtained in this way usually has an expansion ratio of 5 to 5.
It is about 200 times as large, and the apparent density of the foam varies depending on the amount of inorganic matter contained in the foamable composition.
It is about 0.5g/cn+3. Furthermore, even when a foamable composition containing not only inorganic particulates but also inorganic fibrous materials is used, a foam having a high closed cell ratio can be obtained, and the closed cell ratio is about 60% or more.

The CPVC foam of the present invention and its manufacturing method will be explained below based on Examples, but the present invention is not limited to these Examples.

Examples 1 to 7 The total amount of raw materials shown in Table 1 was 500 g in the proportions shown in Table 2.
The mixture was mixed for 45 minutes using a closed double-arm kneader with an effective capacity of 1 g.

The composition after kneading is prepared in a cavity size of 160mm x 160n.
The mixture was filled into an unX 22mm aluminum alloy mold, the mold was covered with an aluminum plate, and the mixture was set in a hydraulically driven heating press and heated from room temperature (approximately 209°C) to 175°C in 10 minutes.

The clamping pressure of the press is approximately 150 per cm2 of mold area.
It was kg.

After holding the temperature at 175℃ for 35 minutes, cold water was passed through the press cooling plate to bring the mold temperature to the appropriate foaming temperature (approximately 10 to 25℃).
) in about 10 minutes, and then maintained at a temperature suitable for foaming for about 30 minutes.

Thereafter, when the clamping pressure of the press was released, the contents of the mold completed foaming in about 1 second.

All of the foams obtained had a beautiful appearance, and the uniformity of the cells on the cut surface was also good. Next, the weight, apparent density, expansion ratio, and closed cell ratio of each component contained in 10 m3 of the foam obtained were examined. The results are shown in Table 2.

(Weight of each component contained in foam 1c113) It was determined by the following formula.

In addition, each component contained in the foam l cni is CPV
C1 refers to inorganic fibrous materials or inorganic granular materials.

(Apparent density) Cut a 20 mm square or 25 mm square cube or a 75 mm x 25 mm x 15+ nm rectangular parallelepiped from the foam,
The volume and weight were calculated using seven rules.

(Foaming ratio) It was calculated using the following formula.

[Expansion ratio] [Weight of CPVC packed in 1 cm3 of foam] (closed cell ratio) Based on ASTM D2856, it was measured using an air comparison type specific gravity model manufactured by Toshiba Beckman ■.

Comparative Example 1 The same conditions and procedures as in Example 1 were adopted except that toluene was not used, but the mold contents did not foam at all.

Comparative Example 2 The raw materials shown in Table 2 were blended in the proportions shown in Table 2, and foams were produced according to the methods of Examples 1 to 7. When the mold was opened, it foamed, but it immediately shrunk and a good foam could not be obtained.

[Margin below] Examples 8 to 19 and Comparative Examples 3 and 4 The raw materials shown in Table 1 were blended in the proportions shown in Table 3 so that the total amount was 3 kg, and stirred for 30 minutes with a Henschel mixer.

Next, this mixture and solvent were put into a pressure kneader, and 5
Stirring was carried out for 30 minutes at 0 to 80°C to obtain a lumpy composition. Thereafter, the composition is filled into a mold using a pressing method, at a temperature of 175°C and a pressure of 1[10°C] applied to the mold.
kg/cd for 35 minutes, then heated at 20 kg/cd for 35 minutes.
After cooling to ℃, the mold was opened and the contents of the mold were released to atmospheric pressure to obtain a foam. After being left at room temperature, it was cured in a hot air dryer at 80°C, and its apparent density, dimensional retention, and combustion properties were examined. The apparent density was determined using the same method as in Examples 1 to 7, and the dimensional retention and combustion properties were determined using the methods described below. The results are shown in Table 3.

(Dimensional retention rate) A sample with dimensions of 75×25×15 mm+ was left in a hot air dryer at 200° C. for 1 hour. Dimensions of each side 1 before leaving
1 + , Ill 2 , D 3I! ++n and dimensions of each side after leaving 1-+, D-2, 1)-3111111
was measured, and the dimensional retention rate was determined using the following formula.

[Dimensional retention rate] = [CQ-+/Ωl) x (Ω'2/g2
)X (Ω-3/(13)] 1/3x 100 [%] If the sample deforms significantly after the test, soak the sample in water and calculate the volume (V) of the sample before the test and the volume (V) of the sample after the test. The volume (V') of the sample was measured, and the dimensional retention rate was determined using the following formula.

[Dimension retention rate] -(V-/V) X 100[
%] (Flammability) A surface test according to JIS A 1321 was conducted, and the area retention rate after the test was measured.

As can be seen from the results in Table 3, the dimensional retention of the foams obtained in Comparative Examples 3 and 4 was significantly reduced when the weight of asbestos in the lcni was reduced to almost zero. This is because asbestos in the form of inorganic fibers has the properties of being flame retardant, including shape retention during combustion, and having a large dimensional retention effect at high temperatures exceeding the softening point, even with a small amount.

Examples 20 to 25 and Comparative Examples 5 and 6 The raw materials shown in Table 1 were blended in the proportions shown in Table 3, and foams were produced according to the method of Examples 1 to 7.

Place this foam in a hot air circulation oven at 40-60℃ for 1 hour.
It was left to stand for ~2 days and the remaining solvent was removed by volatilization.

As for the physical properties of the obtained foam, the weight, apparent density, expansion ratio, and dimensional retention of each component contained in the foam 1cIIi were investigated. The results are shown in Table 3.

[Left below] Examples 26 to 33 The raw materials shown in Table 1 were blended in the proportions shown in Table 4, foams were produced according to the methods of Examples 20 to 25, and the remaining solvent was removed. .

A test piece measuring 220 x 220 x 25 mm was cut out from the foam and subjected to a surface test based on JIS A 1321.

Separately, a 20 mm square cube was cut out from the foam, and the apparent density and closed cell ratio were measured.

These results are shown in Table 4.

Comparative Example 7 A foam was produced and evaluated using the same t and l as in Example 26, except that CLP was not used. After surface testing, the specimen turned into ashes, developed many small cracks, and collapsed when removed from the furnace. The results are shown in Table 4.

Comparative Example 8 A foam was produced and evaluated in the same manner as in Example 27, except that CLP was not used. After the surface test, the test piece had ashes and several small cracks had appeared, but it was possible to take it out from the heating furnace. The results are shown in Table 4.

[Margins below] [Effects of the Invention] The inorganic-containing chlorinated vinyl chloride resin foam of the present invention has improved shape deformation caused by heating of the CPVC foam that does not contain inorganic substances, and can be used under high lH conditions such as in the event of a fire. No harmful shrinkage occurs even when exposed to
In addition, it has excellent heat resistance and flame retardancy, and produces a small amount of heat and smoke when burned, so it can be used in a wide range of applications such as insulation materials, shrines, chemical equipment parts, electrical parts, and vehicle parts. Also, those containing phosphate ester have a chlorine content of approximately 68% by weight? cpv of 6 or more
Even if the foam is based on c, it is possible to prevent the ashing phenomenon when forced combustion is performed.

According to the production method of the present invention, by using a solvent that has the ability to gel CPVC, the CPVC and the solvent form a uniform gel phase, and by embedding the inorganic substance in this gel, a large amount of the inorganic substance can be naturally present. It is possible to easily produce a CPVC foam that has a beautiful appearance and good cell uniformity on its cut surface.

Claims (1)

[Scope of Claims] 1. An inorganic-containing chlorinated vinyl chloride resin foam having a dimensional retention of 70% or more and an expansion ratio of 5 times or more when heated at 200°C for 1 hour. 2. The inorganic material-containing chlorinated vinyl chloride resin foam according to claim 1, wherein the inorganic material contains an inorganic fibrous material. 3 The content of inorganic fibrous substances is 0.0% per 1 cm^3 of volume.
The inorganic material-containing chlorinated vinyl chloride resin foam according to claim 2, which has a weight of 0.01 g or more. 4. The inorganic material-containing chlorinated vinyl chloride resin foam according to claim 2 or 3, wherein the inorganic fibrous material contains asbestos. 5. The inorganic material-containing chlorinated vinyl chloride resin foam according to claim 2 or 3, wherein the inorganic fibrous material contains glass fiber. 6. The inorganic material-containing chlorinated vinyl chloride resin foam according to claim 2 or 3, wherein the inorganic fibrous material contains rock wool. 7. 0.01g of asbestos or rock wool per 1cm^3 volume
The inorganic-containing chlorinated vinyl chloride resin foam according to claim 1, which contains the above. 8. The inorganic-containing chlorinated vinyl chloride resin according to claim 1, which contains 0.06 g or more of inorganic particulate matter per 1 cm^3 in volume. 9. The inorganic-containing chlorinated vinyl resin according to claim 1, which contains an inorganic fibrous material and an inorganic particulate material. 10. The inorganic-containing chlorinated vinyl chloride resin foam according to claim 1, 3, or 8, wherein the chlorinated vinyl chloride resin has a chlorine content of 57 to 75% by weight. 11. The inorganic-containing chlorinated vinyl chloride resin foam according to claim 1, 3, or 8, which has an expansion ratio of 5 to 200 times. 12. The inorganic-containing chlorinated vinyl chloride resin foam according to claim 1, 3, or 8, which contains a phosphoric acid ester. 13. The inorganic-containing chlorinated vinyl resin foam according to claim 12, wherein the phosphoric acid ester is an orthophosphoric acid ester. 14. The inorganic-containing chlorinated vinyl resin foam according to claim 12, wherein the phosphoric acid ester contains 7% by weight or more of phosphorus. 15. The inorganic-containing chlorinated vinyl chloride resin foam according to claim 12, wherein the phosphoric acid ester contains a halogen atom as a constituent element in addition to phosphorus. 16. The inorganic-containing chlorinated vinyl chloride resin foam according to claim 12, wherein the phosphoric acid ester is trischloroethyl phosphate. 17. The chlorinated vinyl chloride resin foam according to claim 12, wherein the ratio of the phosphoric acid ester to 100 parts by weight of the chlorinated vinyl chloride resin is 5 to 50 parts by weight. 18. The inorganic material-containing chlorinated vinyl chloride resin foam according to claim 12, wherein the inorganic material contains antimony trioxide together with an inorganic fibrous material. 19 Chlorine content of chlorinated vinyl chloride resin is 68 to 75
13. The foam of claim 12, which is % by weight. 20 A foamable composition obtained by kneading a chlorinated vinyl chloride resin, an inorganic substance, a decomposable blowing agent, and a solvent is filled into a sealable mold and heated under pressure to melt and gel the chlorinated vinyl chloride resin. A method for producing an inorganic-containing chlorinated vinyl chloride resin foam, which comprises causing decomposition of a decomposable foaming agent, opening a mold at a suitable foaming temperature, and simultaneously foaming. 21 The average degree of polymerization of the chlorinated vinyl chloride resin is 300 to 5
21. The method for producing an inorganic-containing chlorinated vinyl chloride resin foam according to claim 20, wherein the chlorine content is 57 to 75% by weight. 22 Claim 2, wherein the amount of the inorganic substance is 5 to 1000 parts by weight based on 100 parts by weight of the chlorinated vinyl chloride resin.
A method for producing an inorganic-containing chlorinated vinyl chloride resin foam according to item 0. 23 Claim 2, wherein the amount of the inorganic substance is 80 to 500 parts by weight based on 100 parts by weight of the chlorinated vinyl chloride resin.
A method for producing an inorganic-containing chlorinated vinyl chloride resin foam according to item 0. 24. The method for producing an inorganic-containing chlorinated vinyl chloride resin foam according to claim 20, wherein the solvent has the ability to gel the chlorinated vinyl chloride resin. 25 Claim 2, wherein the amount of the solvent is 60 to 1000 parts by weight based on 100 parts by weight of the chlorinated vinyl chloride resin.
A method for producing an inorganic-containing chlorinated vinyl chloride resin foam according to item 0. 26. A method for producing an inorganic-containing chlorinated vinyl chloride resin foam according to claim 20, which contains a stabilizer.