JPH09316268A - Flame-retardant heat-resistant resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition providing a molding excellent in shape retention, by blending a chlorinated vinyl chloride-based resin with hollow spherules composed of aluminum silicate. SOLUTION: This composition is obtained by blending (A) 100 pts.wt. of a chlorinated vinyl chloride-based resin with (B) 3-50 pts.wt. of hollow spherules mainly composed of aluminum silicate of the formula xAl2 O3 .ySiO2 , having <=100μm average particle diameter, 0.1-0.5 bulk specific gravity and containing >=25wt.% of Al2 O3 . For example, a chlorinated vinyl chloride resin having 65% chlorine content obtained by chlorinating a polyvinyl chloride having 560 degree of polymerization is used as the component A. Spherules comprising 35% of Al2 O3 and 60% of SiO2 , having 0.33 bulk specific gravity and 45μm average particle diameter is used as the component B.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a flame-retardant heat-resistant resin composition. In particular, the present invention relates to a flame-retardant heat-resistant resin composition which gives a molded article having good shape retention.

[0002]

2. Description of the Related Art A resin which is flame-retardant and has excellent heat resistance is desired in the field of making products attached to houses and vehicles. From the viewpoint of heat resistance, thermosetting resins are generally superior to thermoplastic resins. However, the thermosetting resin is not suitable for forming a molded product by a highly efficient molding method such as an extrusion molding method. Further, among thermoplastic resins, various ones have been proposed as having excellent heat resistance, but it is difficult to obtain a large amount of a resin that has not been industrially mass-produced at a low cost. Not suitable for general use. Therefore, the thermoplastic resin must be selected from those that can be industrially supplied in large quantities and at low cost.

On the other hand, most of the thermoplastic resins are originally flammable and few are flame-retardant. There are various known methods for making an originally flammable material flame-retardant, but most of them are methods of mixing a resin with a flame-retardant agent. However, if a flame retardant is added to the resin, heat resistance, strength, etc. are deteriorated, and other additives are adversely affected, which cannot be satisfied. Therefore, as the thermoplastic resin, it is desirable to select and use from among flame retardant resins.

As a result of selecting the resin from this point of view, the present inventor has noticed that a chlorinated vinyl chloride resin (hereinafter referred to as CPVC) is suitable as the resin. CPVC is obtained by chlorinating vinyl chloride resin (hereinafter referred to as PVC), and retains the flame retardancy of PVC and is an improvement of the disadvantage of PVC that is poor in heat resistance. ing. That is, since PVC has a low heat distortion temperature and softens when heated to 60 to 70 ° C., it cannot be used, for example, to make a pipe through which hot water passes, but CPVC has a heat distortion temperature of 20 to 40 than PVC. ℃
It is also expensive and can be used to make hot water pipes. Therefore, CPVC has both flame retardancy and heat resistance.

However, it is not easy to heat CPVC into a molded body by heating it. It is for example CPVC
If you try to put it in an extruder for extrusion, CPVC
Is because when it is heated in the extruder, it is easily decomposed, and when it is heated and melted, the melt viscosity is high, and the extrusion operation itself is not easy. But these difficulties are
Stabilizers have been added to prevent the decomposition of PVC, CPVC
To some extent, property improvers have been added to reduce the melt viscosity of the above, and lubricants have been added to smooth the extrusion.

As the stabilizer, for example, a tin-based stabilizer such as dioctyl tin malate, an inorganic lead stabilizer such as tribasic lead sulfate, and a metallic soap such as lead stearate and calcium stearate are used. As the property modifier, acrylonitrile / butadiene / styrene terpolymer (ABS), methacrylic acid / butadiene / styrene terpolymer (MBS), acrylonitrile / butadiene rubber (NBR), etc. were used. . Further, as the lubricant, ester wax, paraffin wax,
Waxes such as

However, the addition of property modifiers and lubricants reduces the flame retardancy and heat resistance of CPVC. In particular, the property improving agent cannot exhibit its effect unless it is added in a relatively large amount, so that it is inevitably added in a large amount.
It tends to undermine the strengths of VC. In addition, the molded article of the CPVC composition thus obtained has poor shape retention,
Since it is easily deformed during or immediately after the molding operation, it is difficult to mold it into a desired shape.

The disadvantage of CPVC of poor shape retention can be solved by adding an inorganic filler to it. For that purpose, calcium carbonate, talc, clay and the like have been added to CPVC. However, such a filler does not have the effect of improving the shape-retaining property unless it is added in a large amount, and if a large amount of this is added, it becomes difficult to mold the obtained composition, and the composition is The density of the product increases, and the molded product becomes heavy, which is inconvenient to use. Therefore, improvement of this point was desired.

[0009]

SUMMARY OF THE INVENTION The present invention seeks to remedy the above-mentioned drawbacks. That is, the present invention is a resin composition that is easily molded, the molded product obtained by molding has good shape retention, is relatively small in density and lightweight, and is flame retardant and heat resistant. Another object of the present invention is to provide a resin composition capable of obtaining a sufficient molded product.

[0010]

The present inventor has found that CPVC
Various compounds were blended with each other, and the resulting blend was extrusion-molded, and the ease of molding and the physical properties of the obtained molded body were measured. At this time, the present inventor added hollow microspheres made of an inorganic material such as shirasu balloon to CPVC,
It was thought that the obtained compound would solve the above problems. However, we have found that extrusion molding the compound containing Shirasu balloon does not result in a molded body having a density as low as expected. It was found that the cause was that the shirasu balloon was destroyed during the extrusion process and was not hollow in the molded body.

Further, the present inventor has tried to blend artificial hollow microspheres into CPVC. The Shirasu balloon is a naturally generated microsphere as described above, and is a hollow microsphere in which gas-containing volcanic ejecta releases gas in the air. Its composition is mainly composed of aluminum silicate, and similarly, various artificial materials mainly composed of aluminum silicate are known. For example, Ichikasei Co., Ltd. sells hollow microspheres containing aluminum silicate as the main component under the trade name Winlite, and Chichibu Onoda Co. sells hollow microspheres containing aluminum silicate as the main component under the name Microcells. ing.

Among them, for winlite, hollow microspheres having an average particle size of 100 μm or less and a bulk specific gravity of 0.1 to 0.5 are selected as hollow microspheres.
When the mixture was blended with VC and the mixture was extruded, it was found that the obtained molded body did not have a low density as expected, as in the case of the aforementioned Shirasu balloon. However,
For Microcells, the average particle size is 10
When hollow microspheres having a bulk specific gravity of 0.1 to 0.5 and having a particle diameter of 0 μm or less are selected, and the mixture is mixed with CPVC and the mixture is extruded and molded, the obtained molded body has a small density, It turned out to be a solution to the problem.

Then, as a result of studying the difference between Winlite and microcells, it was found that the difference was in the content of Al ₂ O _{3 in} aluminum silicate.
That is, Winlite has a small amount of Al ₂ O ₃ of 12 to 17% by weight, but Microcells has a small amount of Al ₂ O ₃ of 3.
It was found that the difference was that it contained a large amount of Al ₂ O ₃ , accounting for 5% by weight. Further, aluminum silicate is represented by the general formula xAl ₂ O ₃ · ySiO ₂ , but the reason why the density of the obtained molded body is as described above is that aluminum silicate contains about 25% by weight of Al. It was found that there is a boundary where ₂ O ₃ is contained. The present invention has been completed based on such knowledge.

The present invention relates to a resin composition comprising 100 parts by weight of CPVC and 3 to 50 parts by weight of hollow microspheres mainly composed of aluminum silicate represented by the general formula xAl ₂ O ₃ .ySiO _2. The microspheres have an average particle size of 100 μm or less and a bulk specific gravity of 0.1 to 0.5.
A flame-retardant heat-resistant resin composition, characterized in that it contains Al ₂ O ₃ in an amount of at least wt%.

According to the present invention, among the hollow microspheres represented by xAl ₂ O ₃ .ySiO ₂ containing aluminum silicate as a main component, those containing a large amount of Al ₂ O ₃ are selected and used. It is the skeleton. The hollow microspheres have an average particle size of 100 μm or less and a bulk specific gravity of 0.1 to 10.
It needs to be 0.5. The hollow microspheres are made of an inorganic material represented by the general formula xAl ₂ O ₃ · ySiO ₂ and containing aluminum silicate as a main component, and the content of Al ₂ O _3, that is, alumina is 25% by weight.
It is necessary to contain a large amount so as to occupy the above.

Typical hollow microspheres as described above are those sold by Chichibu Onoda Co. under the name Microcells. A product called Microcells contains, for example, Al ₂ O ₃ occupying 38% by weight, and
₂ accounts for 60% by weight. Therefore, Microcells corresponds to those having aluminum silicate represented by xAl ₂ O ₃ .ySiO ₂ as a main component.

According to its catalog, Microcells:
True specific gravity of 0.68~0.70g / cm ^3, a bulk specific gravity of 0.4 g / cm ^3, compressive strength 700 kgf / c
It is said that it has m ² , a melting point of 1600 ° C. and zero water absorption. Since the particle size is said to be in the range of 20 to 300 μm, one having an average particle size of 100 μm or less must be selected and used from the above for use in the present invention. Further, it is said that the microcells have a completely spherical shape, and when cut, they contain only one concentric spherical cavity inside. Therefore, Microcells hardly breaks the particles even if it is mixed with CPVC and put into an extruder and extrusion molding is performed.

The reason why the present invention uses microspheres of 100 μm or less is that it is easy to mix them with CPVC to form a composition, and when the composition is formed into a molded body, the appearance of the molded body is beautiful. It comes from Sato. Average particle size is 100
If you used a small ball that exceeds μm,
It is difficult to mix and knead with C to obtain a uniform composition, and when this is used as a molded body, the molded body has a poor appearance. The reason why the present invention uses hollow microspheres having a bulk density of 0.1 to 0.5 is that
It is nothing more than trying to reduce the density of the resin composition after compounding it with PVC. This is because it is difficult to mix the hollow microspheres having a bulk specific gravity of less than 0.1 with CPVC and kneading them to form a uniform composition. On the contrary, the bulk specific gravity is 0.
When it exceeds 5, the density of the composition becomes large when it is mixed with CPVC to form a composition, and the characteristic of being lightweight is lost.

The reason why the present invention uses hollow microspheres made of aluminum silicate containing 25% by weight or more of Al ₂ O ₃ is that the microspheres are mixed with CPVC and kneaded as described above. Is derived from the stability of. That is, in general, aluminum silicate is xAl ₂ O ₃ · ySi.
Where it is represented by the chemical formula of O ₂ , of which A
Hollow microspheres containing 25% by weight or more of l ₂ O ₃ are
The sphere is not destroyed even if a considerable amount of pressure is applied. However, the hollow microspheres made of aluminum silicate containing less than 25% by weight of Al ₂ O ₃ are destroyed when compounded with CPVC and the mixture is put into an extruder and extruded. This is a fact confirmed by the inventor. For this reason, in the present invention, 25% by weight or more of A
Hollow microspheres mainly containing aluminum silicate containing l ₂ O ₃ are selected and used.

In the present invention, CPVC is used as the resin. CPVC is made by chlorinating PVC as described above. Since PVC has a chlorine content of 56.8% by weight, CPVC has various grades with a chlorine content of 56.8% by weight or more. Cause Among them, those having a chlorine content of 60% by weight or more are preferably used. This is because one having a chlorine content of 60% by weight or more has excellent heat resistance. The raw material PVC is not limited to a vinyl chloride homopolymer and may be a copolymer with another monomer. For example, it may be a copolymer of vinyl chloride and vinyl acetate, but the copolymer must contain 80% by weight or more of vinyl chloride. Also, the production method of PVC is not particularly limited, but the polymerization degree of PVC is CP derived from this.
In order to make the VC suitable for extrusion molding, it is preferably in the range of 500 to 1400.

Various methods can be used to chlorinate PVC to CPVC. That is, a vapor phase method, a suspension method, a solution method, and the like can be adopted, and CPVC chlorinated by any one of them can be used.

In the present invention, the mixing ratio of the hollow microspheres is 1
3 to 50 parts by weight with respect to 00 parts by weight of CPVC. The reason is that the effect of blending the hollow microspheres does not remarkably appear when the blending ratio of the hollow microspheres is less than 3 parts by weight.
On the contrary, if the amount exceeds 50 parts by weight, the composition obtained on the contrary becomes difficult to mold. Among them, the blending ratio is preferably 5 to 30 parts by weight.

In the present invention, various additives that have been used so far can be added to CPVC. Additives include stabilizers, property modifiers, lubricants, colorants, processing aids, reinforcing agents and fillers. However, the blending amount must be 40 parts by weight or less with respect to 100 parts by weight of CPVC.

As the stabilizer, tin-based stabilizers, lead-based stabilizers, metal soaps, epoxy-based stabilizers, phosphoric acid ester-based stabilizers and the like can be used. For example, dibutyltin malate can be used as the tin-based stabilizer, tribasic lead sulfate and lead stearate can be used as the lead-based stabilizer, and calcium stearate can be used as the metal soap. ABS resin (acrylonitrile-butadiene-styrene copolymer), MBS resin (methyl methacrylate-butadiene
Styrene copolymer), EVA (ethylene / vinyl acetate copolymer) and the like can be used. As the lubricant, stearic acid or ester wax can be used.

[0025]

According to the present invention, 100 parts by weight of CPVC has an average particle diameter of 100 μm or less and a bulk specific gravity of 0.1 to 100 μm.
Since 3 to 50 parts by weight of hollow microspheres containing 0.5 parts of aluminum silicate as a main component were blended to form a composition, the composition is easy to prepare, and the composition thus obtained is Good shape retention during extrusion molding, flame retardant, and heat resistance. In addition, as the hollow microspheres, it was decided to use the hollow microspheres containing 25% by weight or more of Al ₂ O ₃ constituting the hollow microspheres. Keeps its shape without being destroyed,
Therefore, the molded product obtained by molding has a relatively low density and is lightweight. For this reason, the composition is suitable for making molded bodies for homes and motor vehicles.

Hereinafter, the advantages of the composition according to the present invention will be specifically described with reference to Examples and Comparative Examples. In the following, simply parts or% means parts by weight or% by weight.
Is the meaning of.

[0027]

Example 1 In this example, polyvinyl chloride having a degree of polymerization of 560 was chlorinated to use CPVC having a chlorine content of 65%. Also, 35% Al ₂ O ₃ as hollow microspheres,
SiO ₂ microspheres having a bulk density of 0.33 and an average particle diameter of 45 μm (trade name: Microcells SL-75 manufactured by Chichibu Onoda Co.) were used.

5 parts of the hollow microspheres were added to 100 parts of the CPVC, and 4 parts of tribasic lead sulfate as a stabilizer was added thereto.
2 parts of lead stearate, 1 part of calcium stearate, wax as a lubricant (made by Hoechst Japan Co., wax O
P) 1 part and MBS 10 parts as a property improver were mixed, and this mixture was mixed well. This mixture was put into an extruder and extruded. At that time, 2.5 at the tip of the extruder
A slit of mm × 21 mm was opened, and the composition was extruded as a flat plate from this slit.

The specific gravity of the obtained flat plate was measured according to JIS K-7112, and the shape retention was visually judged by the degree of sagging of the molten resin discharged from the mold during extrusion molding, and the appearance was extruded. The smoothness of the surface of the molded product was visually judged.

The molded product had a specific gravity of 1.37, good shape retention, and good appearance.

[0031]

Example 2 In this example, a flat plate was obtained in the same manner as in Example 1 except that the amount of hollow microspheres added was increased to 10 parts.

The specific gravity of the obtained flat plate was 1.30, the shape retention was good, and the appearance was also good.

[0033]

Example 3 In this example, a flat plate was obtained in the same manner as in Example 1 except that the amount of hollow microspheres added was increased to 30 parts.

The specific gravity of the obtained flat plate was 1.15, the shape retention was good, and the appearance was also good.

[0035]

[Example 4] In this example, the hollow microspheres in Example 1 were changed to 38% Al ₂ O _{3 and} 60% SiO _2.
Microspheres having a bulk specific gravity of 0.34 and an average particle size of 80 μm (manufactured by Chichibu Onoda Co., trade name Microcells SL-12
A flat plate was obtained in the same manner as in Example 1 except that 10 parts of 5) was used.

The specific gravity of the obtained flat plate was 1.30, and the shape retention and the appearance were good.

[0037]

COMPARATIVE EXAMPLE 1 In this comparative example, hollow microspheres were not used, but instead of ABS resin (acrylonitrile content of 2
5%, butadiene content 50%, styrene content 2
A flat plate was obtained in the same manner as in Example 1 except that 60 parts of 5%) was used.

The specific gravity of the obtained flat plate was 1.28, but the shape retention was poor and the appearance was not good.

[0039]

[Comparative Example 2] In this comparative example, the hollow microspheres obtained in Example 1 were Al ₂ O ₃ of 15%, SiO ₂ of 75%, an average particle diameter of 150 μm, and a bulk specific gravity of 0.31. Made, product name Winlite SB-9011) 10
A flat plate was obtained in the same manner as in Example 1 except that a part was used.

The specific gravity of the obtained flat plate was 1.48, which was unsuitable because it was large. The shape retention was good, but the appearance was poor.

[0041]

Comparative Example 3 In this comparative example, a flat plate was obtained in the same manner as in Example 1 except that hollow microspheres were not used in Example 1.

Since the specific gravity of the obtained flat plate was 1.48, which was large, it was unsuitable, the shape retention was good, and the appearance was also good.

[0043]

[Comparative Example 4] In this comparative example, a shirasu balloon having a content of Al ₂ O ₃ of 13% and a content of SiO ₂ of 76% (trade name MSB-501) was used as the hollow microspheres in Example 1.
A flat plate was obtained in the same manner as in Example 1 except that 10 parts of 1) was used.

The obtained flat plate had a good shape-retaining property but a large specific gravity of 1.43 and a bad appearance.

[0045]

COMPARATIVE EXAMPLE 5 In this comparative example, the hollow microspheres in Example 1 contained 38% Al ₂ O _{3 and} 60% SiO ₂ , the average particle size was large, 130 μm, and the bulk specific gravity was 0.41. Example 1 except that 10 parts (trade name, Microcells SLG, manufactured by Chichibu Onoda Co., Ltd.) were used.
A flat plate was obtained by carrying out the same procedure as above.

The obtained flat plate has good shape retention,
The specific gravity was 1.31, which was good, but the appearance was poor.

Claims (1)

[Claims] 1. A resin composition comprising 100 parts by weight of a chlorinated vinyl chloride resin and 3 to 50 parts by weight of hollow microspheres mainly composed of aluminum silicate represented by the general formula xAl ₂ O ₃ .ySiO _2. The hollow microspheres have an average particle size of 100 μm or less, a bulk specific gravity of 0.1 to 0.5, and contain 25% by weight or more of Al ₂ O ₃ , flame-retardant heat resistance. Resin composition.