JPH059307A - Waterproof sheet - Google Patents

Abstract

PURPOSE:To provide a waterproof sheet having good weather ability over a long period of time. CONSTITUTION:A waterproof sheet is formed from a thermoplastic elastomer composition comprising (a) 10-35wt.% of an olefinic thermoplastic elastomer, (b) 65-90wt.% of a crystalline polyolefin, (c) an inorganic filler in an amount of <=40 pts. wt. per 100 pts.wt. of the sum of components (a) and (b), and (d) three kinds of the additives inclading: (1) 0.01-1.0 pt.wt. of a hindered phenolic compound, (2) 0.01-1.0 pt.wt. of a benzotriazole compound and (3) 0.01-1.0 pt.wt. of a hindered amine compound of a benzoate compound.

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a waterproof sheet molded from a thermoplastic elastomer composition, and more particularly to a waterproof sheet having good weather resistance.

[0002]

2. Description of the Related Art Thermoplastic elastomers are widely used in various industrial products such as automobile parts as a material that fills the gap between rubber and plastic or as a substitute material for rubber. again,
This thermoplastic elastomer is also used in various waterproof sheets including so-called civil engineering sheets used at various construction sites. Waterproof sheets used in civil engineering waterproof construction methods include those formed from a composition containing vulcanized rubber as a main component, those formed from a thermoplastic elastomer composition, and the like.

[0003] Waterproof sheets are widely used outdoors such as in industrial waste disposal sites, ponds for agriculture, and ponds such as golf courses. In order to prevent deterioration due to ultraviolet rays,
Generally, triazole-based, benzophenone-based, or salicylic acid ester-based weather stabilizers are added to resin compositions for producing waterproof sheets. Synthetic rubber components and various inorganic fillers are also added to improve not only weather resistance but also moldability and other physical properties.

[0004] However, when synthetic rubber or various inorganic fillers are added to a thermoplastic elastomer, the weather resistance may not be improved even if a weather stabilizer such as a triazole, benzophenone, or salicylic acid ester is added. rice field. Moreover, even if a certain degree of weather resistance was provided, it did not last for a long period of time.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a waterproof sheet having good weather resistance over a long period of time.

[0006]

Means for Solving the Problems As a result of intensive research in view of the above objects, the present inventors have found that the thermoplastic olefinic elastomer, the crystalline polyolefin, and the inorganic filler are each blended in specific amounts, and furthermore, specific The present inventors discovered that a waterproof sheet made of a composition to which specific amounts of the three types of compounds are added maintains good weather resistance over a long period of time, and arrived at the present invention.

That is, the waterproof sheet of the present invention comprises (a) 10 to 35% by weight of olefinic thermoplastic elastomer, (b) 65 to 90% by weight of crystalline polyolefin, and (a) + (b) 10% by weight.
(c) 40 parts by weight or less of an inorganic filler, and (d) the following three additives: (a) 0.01 to 1.0 parts by weight of a hindered phenol compound, and (b) a benzotriazole compound 0.01 to 1.0 parts by weight, and (c) 0.01 to 1.0 parts by weight of a hindered amine compound or a benzoate compound.

The present invention will now be described in detail. First, each component of the thermoplastic elastomer composition, which is a raw material for the waterproof sheet of the present invention, will be described.

(a) Olefinic Thermoplastic Elastomer The (a) olefinic thermoplastic elastomer used in the present invention is obtained by dynamically heat-treating an olefinic copolymer rubber and a polyolefin to partially crosslink them. It is.

[0010] As the olefinic copolymer rubber used in the production of the olefinic thermoplastic elastomer, two or more of α-olefins such as ethylene, propylene, 1-butene, 1-hexene and 4-methyl-pentene are used. of copolymer rubbers. Typical copolymer rubbers include ethylene-butene copolymer rubber (EBR), ethylene-propylene copolymer rubber (EPR) and ethylene-propylene-diene copolymer rubber (EPDM). . As the diene in the ethylene-propylene-diene copolymer (EPDM), use non-conjugated dienes such as dicyclopentadiene, 1,4-hexadiene, cyclooctadiene and methylenenorbornene, or conjugated dienes such as butadiene and isoprene. can be done.

The content of ethylene in such olefinic copolymer rubber is 20-90% by weight, preferably 35% by weight.
~80% by weight. an ethylene content of less than 20% by weight;
Alternatively, when it exceeds 90% by weight, it becomes difficult to exhibit properties as an elastomer. In addition, the iodine value (degree of unsaturation) is 30
and the Mooney viscosity ML ₁₊₈ (127° C.) is preferably 5-300. The crystallinity of such olefinic copolymer rubber is usually 40% by weight or less.

[0012] Next, polyolefins that can be used in the production of olefinic thermoplastic elastomers include:
isotactic polypropylene, propylene and other α
- Using copolymers with olefins, such as propylene-ethylene copolymers, propylene-1-butene copolymers, propylene-1-hexene copolymers, propylene-4-methyl-1-pentene copolymers, etc. be able to.

An olefinic thermoplastic elastomer is produced from the above olefinic copolymer rubber and polyolefin. Partial cross-linking with an organic peroxide gives an elastomer with suitable flexibility.

When an olefinic elastomer is prepared by using an olefinic copolymer rubber, polypropylene, brominated butyl rubber, and a mineral oil-based softening agent, the blending amounts are preferably as follows. . Specifically, 10 to 100 parts by weight of polypropylene, 0 to 90 parts by weight of brominated butyl rubber, and 10 to 120 parts by weight, preferably 20 to 120 parts by weight, of olefinic copolymer rubber per 100 parts by weight of polypropylene + brominated butyl rubber. 100 parts by weight and 10 to 150 parts by weight, preferably 20 to 120 parts by weight of a mineral oil-based softening agent are mixed with 100 parts by weight of polypropylene plus brominated butyl rubber.

The amount of organic peroxide added is 0.1 to 5 parts by weight per 100 parts by weight of the above components.
It is preferably 1 to 2 parts by weight.

[0016] Such an olefinic thermoplastic elastomer preferably has a degree of cross-linking of 5 to 60% (ratio to the total elastomer composition) and a hardness of 50 to 95 according to JIS A.

The olefinic thermoplastic elastomer can be produced by mixing the components described above and dynamically heat-treating, ie, melt-kneading. As the kneading device, conventionally known devices such as open type mixing rolls, non-open type Banbury mixers, extruders (including twin-screw mixers), kneaders, and continuous mixers can be used. Among these, it is preferable to use a non-open type apparatus, and it is preferable to knead in an atmosphere of an inert gas such as nitrogen or carbon dioxide gas. The kneading temperature is appropriately set according to the melting points of polyolefin, halogenated butyl rubber, olefinic copolymer rubber, and the like. The kneading time should be 1 to 30 minutes, preferably 5 to 10 minutes.

(b) Crystalline polyolefin The crystalline polyolefin that can be used in the present invention includes homopolymers of α-olefins such as ethylene, propylene, butene-1, hexene-1, and 4-methylpentene-1; Non-elastomeric copolymers with propylene or other α-olefins, or non-elastomeric copolymers of two or more of these α-olefins, or homopolymers, copolymers, or even homopolymers thereof A blend of a polymer and a copolymer or the like can be used.
Crystalline polyethylene obtained by copolymerizing ethylene alone or ethylene with an α-olefin (preferably having 4 to 8 carbon atoms) such as propylene, 1-butene or 1-pentene is preferably used.

The density of crystalline polyethylene is 0.90-0.97.
g/cm ³ , preferably 0.91 to 0.94 g/cm ³ , melt index (MI: 190°C, load of 2.16 kg, hereinafter the melt index term is the same condition) 0.1 to 50
g/10 min, preferably 0.5 to 20 g/10 min. If the density is less than 0.90 g/cm ³ , the physical properties such as tensile strength of the sheet are remarkably lowered. Also, when the density exceeds 0.97,
It is not preferable because the flexibility of the sheet is deteriorated.

On the other hand, if the melt index is less than 0.1, the sheet moldability will deteriorate, which is not preferable. On the other hand, if the melt index exceeds 50, kneadability with the olefinic thermoplastic elastomer deteriorates, which is not preferable.

Processability of the thermoplastic elastomer composition obtained by blending such a crystalline polyolefin;
Heat resistance, mechanical strength, bonding strength, etc. are improved.

(c) Inorganic Filler In the present invention, an inorganic filler is added in addition to the above two components (a) and (b). As a result, the thermal conductivity of the elastomer composition can be enhanced, the stability of the joints of the waterproof sheets can be improved, and the joining time can be shortened.

Specific examples of such inorganic fillers include talc, calcium carbonate, silica, kaolin, alumina, carbon black, clay, asbestos, and glass fiber.

In the present invention, each of the components (a), (b) and
and (c), the following additives are added to further improve weather resistance. (d) Additives for improving weather resistance Additives for improving weather resistance include (a) hindered phenol compounds, (b) benzotriazole compounds, and (c) hindered amine compounds or benzoate compounds. Use

[0025] By using the three types of additives described above, it is possible to improve the weather resistance and prevent cracks and discoloration of the waterproof sheet.

[0026] As the hindered phenol compound,
2,6-di-t-butyl-4-methylphenol, 1,1,3-tri(2-
methyl-4-hydroxy-5-t-butylphenyl)butane, tetrakis[methylene(3,5-di-t-butyl-4-hydroxyhydrocinnamate)]methane, n-octadecyl-β-(4' - Hydroxy-3′,5′-di-t-butylphenyl)propionate, 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene , tris-(3,5-di-t-butyl-4-hydroxybenzyl)isocyanate, pentaerythrityl-tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, and the like. .

Benzotriazole compounds include 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-5'-t-butylphenyl)benzotriazole, 2- (2'-hydroxy
-5'-amylphenyl)benzotriazole, 2-(2'
-hydroxy-4'-octoxyphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-t-butylphenyl)benzotriazole, 2-(2'-hydroxy-3',5' - diisoamylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-dimethylphenyl)benzotriazole, 2-(2'-hydroxy-3'
-t-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3',5'-di-t-
butylphenyl)-5- chlorobenzotriazole, 2-
(2'-Hydroxy-3',5'-dimethylphenyl)-5
- Chlorobenzotriazole, 2-(2'-hydroxy-
3',5'-dichlorophenyl)benzotriazole and the like.

Further, the hindered amine compounds include polycondensates of dimethyl-1-(2-hydroxyethyl)-4-hydroxy-2,2,6,6-tetramethylpiperidine succinate, poly[(6-(1 ,1,3,3-tetramethylbutyl) amino-1,3,5-
triazine-2,4-diyl)((2,2,6,6-tetramethyl-4-
piperidyl)imino) hexamethylene ((2,2,6,6-tetramethyl-4-piperidyl)imino)], N,N′-bis(3-
aminopropyl) ethylenediamine-2,4-bis[N-butyl-N-(1,2,2,6,6-pentamethyl-4-piperidyl)amino]-6-chloro-1,3,5-triazine condensate , bis(2,2,
6,6-tetramethyl-4-piperidyl) sebacate, 2-(3,
5-di-t-butyl-4-hydroxybenzyl)-2-n-butylmalonate bis(1,2,2,6,6-pentamethyl-4-piperidyl) and the like.

Benzoate compounds include phenyl salicylate, p-octylphenyl salicylate, p-butylphenyl salicylate, resorcinol monobenzoate, 2,4-di-t-butylphenyl-3,5-di-t-butyl
-4-hydroxybenzoate, 4-octylphenyl-3,5
- di-t-butyl-4-hydroxybenzoate and the like.

Hindered amine compounds and benzoate compounds are used for the purpose of use of the waterproof sheet,
Either one is appropriately selected and used according to the other components and the like.

In the present invention, each of the components (a), (b) and
In addition to (c) and (d), metal deterioration inhibitors, antistatic agents, pigments and the like can be added as appropriate.

[0032] Next, the blending amounts of the above components will be described. First, the blending amounts of (a) olefinic thermoplastic elastomer and (b) crystalline polyolefin are as follows: (a) olefinic thermoplastic elastomer + (b) crystalline polyolefin is 100% by weight, (a) olefinic 10 to 35% by weight of thermoplastic elastomer, preferably 10 to 30% by weight;
(b) 65-90% by weight of crystalline polyolefin, preferably
70-90% by weight. If the olefinic thermoplastic elastomer is less than 10% by weight, the flexibility of the waterproof sheet is lowered, which is not preferable. On the other hand, if the amount of the olefinic thermoplastic elastomer exceeds 35% by weight, the bonding strength between the waterproof sheets is lowered, which is not preferable.

(c) The amount of the inorganic filler to be blended is 40 parts by weight or less, preferably 30 parts by weight or less per 100 parts by weight in total of the components (a) and (b). 40 inorganic fillers
If the value exceeds the weight part, the flexibility of the resulting sheet will be reduced.

The amount of the additive (d) for improving weather resistance is 0.01 of (a) the hindered phenol compound per 100 parts by weight of the above components (a) + (b). ~1.0
0.01 to 1 part by weight of (b) benzotriazole compound
0 parts by weight, and (c) 0.01 to 1.0 parts by weight of hindered amine compounds or benzoate compounds. Even if one of the above-mentioned additives for improving weather resistance is
If it is less than 0.01 part by weight, the weather resistance will be lowered. Moreover, if even one of the additives for improving weatherability exceeds 1.0 part by weight, the surface of the waterproof sheet will ooze out (blooming) and become cloudy.

[0035] The thermoplastic elastomer composition as a material for sheet molding is prepared by mixing the above components (a) to (d) and optional additives, and then subjecting this mixture to a Banbury mixer, uniaxial Alternatively, using a conventional kneading device such as a twin-screw extruder, a mixing roll, a kneader, a continuous mixer, etc., at 150 to 250°C, preferably 180 to 230°C, 1 to
It is carried out by kneading for about 10 minutes.

[0036] The mixing order (mixing order) of each component is not particularly limited, and is appropriately set according to the materials used.

[0037] For forming a waterproof sheet from the thermoplastic elastomer composition obtained by the above method, a commonly used sheet forming method can be employed as it is. That is, by extruding the molten mixture through a T-die at a temperature of about 180-250° C., a sheet having a thickness of about 0.1-3.0 mm can be easily formed. It is also possible to mold the thermoplastic elastomer composition heated to a softening point or higher into a sheet using a calender roll or the like.

[0038]

In the present invention, a waterproof sheet is made of a thermoplastic elastomer composition obtained by mixing appropriate amounts of an olefinic thermoplastic elastomer, a crystalline polyolefin, an inorganic filler, and three types of additives for improving weather resistance. However, by blending the three types of additives in the above amounts, good weather resistance can be obtained over a long period of time. In addition, the waterproof sheet has not only weather resistance but also the flexibility of the olefinic thermoplastic elastomer and the heat resistance and mechanical strength of the crystalline polyolefin. In addition, the addition of inorganic fillers increases the thermal conductivity of the waterproof sheet, speeding up the bonding process,
The stability of the joint portion is further improved.

[0039]

EXAMPLES The present invention will be explained in more detail by the following examples. First, the method for preparing the olefinic thermoplastic elastomer used in each example and comparative example and other components will be described.

(a) Olefinic thermoplastic elastomer
Preparation 30 parts by weight of propylene-ethylene block copolymer (melt flow rate (MFR, 230°C, 2.16 kg load) 15 g/10 minutes) and ethylene-propylene-diene copolymer: Mooney viscosity ML ₁₊₈ (127°C ) 45, ethylene content 66% by weight, diene component: ethylidene norbornene, iodine value 1
8, 70 parts by weight and brominated butyl rubber (Mooney viscosity ML
₁₊₈ (125°C) 47, bromine content 2% by weight, unsaturation degree 2 mol%) and 10 parts by weight of a softening agent (paraffinic process oil) were mixed, and peroxide was added.
(2,5-Dimethyl-2,5-di(t-butylperoxy)hexyne-3) was added in an amount of 0.3 parts by weight per 100 parts by weight of the above total amount of - and kneaded at 175°C for 3 to 5 minutes, A thermoplastic elastomer was obtained by partial cross-linking. This thermoplastic elastomer had a degree of cross-linking (calculated from paraxylene-insoluble matter) of 40% and a hardness of 70 according to JIS A.

(b) Crystalline Polyolefin LLDPE: Linear low density polyethylene (melt index (MI) 0.9 g/10 min, density 0.920 g/cm ³ ) was used.

(c) Inorganic Filler Heavy calcium carbonate (average particle size 4 μm) was used.

(d) Additives for improving weather resistance (a) Hindered phenol compounds (abbreviated as H-Ph) include pentaerythrityl-tetrakis [3-
(3,5-di-t-butyl-4-hydroxyphenyl)propionate] was used. (b) Benzotriazole compounds (abbreviated as BTA)
As the solvent, 2-(3-t-butyl-5-methyl-2-hydroxyphenyl)-5-chlorobenzotriazole was used. (C) Hindered amine compounds (abbreviated as H-A) include poly[(6-(1,1,3,3-tetramethylbutyl)amino-1,3,5-triazine-2,4-diyl )((2,2,6,6-tetramethyl-4-piperidyl) imino) hexamethylene((2,2,
6,6-tetramethyl-4-piperidyl)imino)] was used. Benzoate compounds (abbreviated as BA) include 2,4-di-t-butylphenyl-3,5-di-t-butyl-4-
Hydroxybenzoate was used.

Examples 1 to 5 and Comparative Examples 1 to 6 Each component was blended in the proportions shown in Table 1, and mixed with a twin-screw kneading extruder.
The mixture was melt-kneaded at a cylinder temperature of 210° C. to obtain a pellet-like kneaded product.

The obtained pellets were molded into sheets by a sheet molding machine to prepare samples.

Table 1 ⁽¹⁾ (d) Component ⁽²⁾ Example No. (a) Component (b) Component (c) Component H-Ph H-A BA BTA Example 1 30 70 10 0.10 0.20 - 0.20 Example 2 30 70 10 0.05 0.05 − 0.05 Example 3 30 70 10 0.50 1.00 − 1.00 Example 4 30 70 10 0.10 − 0.20 0.20 Example 5 10 90 10 0.10 0.20 − 0.20 Comparative example 1 30 0.1 0 0 0.1 2 30 70 10 0.10 − − 0.20 Comparative Example 3 30 70 10 − 0.20 − 0.20 Comparative Example 4 5 95 10 0.05 0.05 − 0.05 Comparative Example 5 50 50 10 0.05 0.05 − 0.05 Comparative Example 6 30 70 50 0.05 − 0.05

Note (1): Unit is parts by weight (2): H-Ph is the above hindered phenol compound, HA is the above hindered amine compound, and BA is the above benzoate compound. a compound and B
TA is the benzotriazole compound mentioned above.

The following tests were performed on each sample. The test method was as follows. (1) Tensile breaking strength (kg/cm ² ): JIS K6310, No. 3 dumbbell, tensile speed was 500 mm/min. (2) Tensile elongation at break (%): According to JIS K 6310. (3) Tear strength: JIS K6310, B type, tensile speed of 500
mm/min. (4) Flexibility: Evaluated according to the following criteria depending on the difference in tensile modulus (kg/cm ² ). Tensile modulus (kg/cm ² ) ○: Less than 1200 △: 1200 or more to less than 1600 ×: 1600 or more (5) Bonding force: The sample is heat-sealed using an automatic heat-sealing machine and peeled at a width of 25 mm Strength (kg/25mm) was measured. (6) Weather resistance: Using an injection-molded test piece of 70 x 30 x 30 mm, this is measured by a sunshine weatherometer (black panel temperature: 83°C, spray/dry cycle: 18 minutes/102 minutes).
An accelerated weathering test was performed using The change in tensile strength of the test piece before and after the accelerated weathering test was measured, and the time required for the retention of tensile strength to reach 50% after the accelerated weathering test was determined. Then, the weather resistance was evaluated according to the following criteria. ○: 2000 hours or more when the retention rate reaches 50% △: 1000 hours or more and less than 2000 hours when the retention rate reaches 50% ×: Less than 1000 hours when the retention rate reaches 50%

Table 2 shows the test results.

Table 2 Tensile rupture Tensile rupture example No. Strength ⁽¹⁾ Elongation ⁽²⁾ Tear strength ⁽³ ) Bonding strength ⁽⁴ ) Flexibility weather resistance Example 1 160 800 75 35 ○ ○ Example 2 160 800 75 35 ○ ○ Example 3 150 750 70 30 ○ ○ Example 4 160 800 75 35 ○ ○ Example 5 150 750 90 35 ○ ○ Comparative example 1 160 800 75 35 ○ × Comparative example 2 160 800 75 35 ○ × Comparative example 3 160 800 75 35 ○ △ Comparative Example 4 170 700 95 40 × ○ Comparative Example 5 120 600 60 30 ○ ○ Comparative Example 6 100 500 50 30 × ×

Note (1) in Table 2: The unit is kg/cm ² . (2) : Unit is %. (3): The unit is kg/cm ² . (4) : Unit is kg/25mm.

As can be seen from the comparison between Examples 1 to 4 and Comparative Examples 1 to 3, even if the types and amounts of components (a) to (c) are the same, the additive for improving weather resistance When there are two types, the weather resistance is inferior. Moreover, as can be seen from the comparison between Example 5 and Comparative Examples 4 and 5, the mechanical properties deteriorate when the ratio of the olefinic thermoplastic elastomer to the crystalline polyolefin is out of the range specified in the present invention. Also, as in Comparative Example 6, when the blending amount of (c) the inorganic filler was larger than the blending range in the present invention, the physical properties were lowered in all the items tested.

[0053]

Effect of the Invention The waterproof sheet of the present invention made of the olefinic thermoplastic elastomer composition has high weather resistance that can withstand long-term outdoor use, and is excellent in mechanical strength, heat resistance and flexibility. is also good. Furthermore, the bonding strength due to heat sealing is large, so that the bonded portion does not break and water leaks do not occur.

The waterproof sheet of the present invention is suitable as a waterproof sheet for long-term outdoor use, and can be used at industrial waste disposal sites,
It can be suitably used for agricultural reservoirs, golf course ponds, and the like.

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Claims (1)

[Claims] [Claim 1] (a) an olefinic thermoplastic elastomer
10 to 35% by weight, (b) 65 to 90% by weight of crystalline polyolefin, (c) 40 parts by weight or less of an inorganic filler, and (d) or less with respect to 100 parts by weight of (a) + (b) (a) 0.01 to 1.0 parts by weight of a hindered phenol compound, (b) 0.01 to 1.0 parts by weight of a benzotriazole compound,
and (c) a waterproof sheet molded from a thermoplastic elastomer composition containing 0.01 to 1.0 parts by weight of a hindered amine compound or a benzoate compound.