JPH0892876A - Waterproof sheet - Google Patents

Abstract

PURPOSE: To prepare a nonpollution sheetlike waterproof material, having excellent executability in the field and physical properties and good in working environment. CONSTITUTION: This waterproof sheet is obtained by impregnating a woven fabric with a poly α-olefin composition comprising (1) 10-100 pts.wt. amorphous poly α-olefin having 100-170 deg.C softening point and 10<-1> to 10Pa.s melt viscosity at 190 deg.C, (2) 90-0 pt.wt. crystalline poly α-olefin and (3) 1-5 pts.wt. carbon black (with the proviso that the total amount of the amorphous poly α-olefin and crystalline poly α-olefin is 100 pts.wt.).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waterproof sheet. The waterproof sheet provided by the present invention is thin, has high strength and high impact resistance, and does not contain a toxic water-soluble substance or a volatile component. , Pollution-free, good working environment, excellent on-site workability such as flexibility and bondability, and
It has many advantages such as good water and chemical resistance.

Therefore, the tarpaulin provided by the present invention is not only a general tarpaulin for building such as rooftop waterproofing, but also for blocking landfill wastewater, preventing pond leakage, and agricultural and industrial drainage canal blocking. It can be used as a so-called civil engineering waterproof sheet such as a waterproof sheet for water, a waterproof sheet for tunnels, etc. to prevent water leakage from revetments and river banks.

[0003]

[Prior art and its problems] Waterproof material (especially for construction)
Conventionally, hot asphalt, which is directly poured and applied on-site, has been the mainstream, but for the purpose of improving weather resistance and workability, polymer-based sheet waterproofing materials and coating waterproofing materials (for example, building construction Handbook 3rd edition, 1974 1
February 1, published by Asakura Shoten, pp. 770-775) and the like have become popular in recent years.

Of these, in particular, the sheet waterproof material is a sheet-shaped waterproof material mainly made of a thermoplastic polymer such as rubber-filled asphalt, synthetic rubber, polyvinyl chloride, high-density polyethylene, ethylene / vinyl acetate copolymer and rubber. Compared to coating type waterproof materials that mainly use thermosetting polymers such as urethane, unsaturated polyester, and epoxy, it has advantages such as easier handling, shorter construction period, and better working environment. Has been done.
However, these waterproof sheets have low strength (rubber-containing asphalt, synthetic rubber, etc.), pollution problems such as elution of water-soluble plasticizers (polyvinyl chloride, etc.), and on-site joining are not easy. Each of them had important problems such as high-density polyethylene and was not always a satisfactory waterproof material.

[0005]

SUMMARY OF THE INVENTION Therefore, the object of the present invention is to improve the above-mentioned drawbacks of the prior art, that is, to have excellent on-site workability and physical properties, and It is to provide a sheet-like waterproof material that is pollution-free and has a good working environment.

[0006]

Therefore, the present inventors have
As a result of extensive studies to solve the above problems, by providing a waterproof sheet obtained by impregnating a woven fabric with a poly α-olefin composition having specific properties,
The inventors have found that the object can be achieved, and have completed the present invention.

That is, according to the present invention, (1) the softening point is 10
10 to 100 parts by weight of an amorphous poly α-olefin having a melt viscosity of 10 ⁻¹ to 10 Pascal · second at 190 ° C., and (2) a crystalline poly α-olefin of 90 to 0 parts by weight, and (3) 1 to 5 parts by weight of carbon black (however, the total amount of the amorphous poly α-olefin and the crystalline poly α-olefin is 100 parts by weight) is used as a woven fabric. This can be achieved by providing a waterproof sheet characterized by being obtained by impregnation.

The present invention will be described in detail below. The amorphous poly α-olefin described in the present invention is a homopolymer of α-olefins or a copolymer thereof (for example,
Propylene homopolymer, propylene / ethylene copolymer, propylene / butene-1 copolymer, etc.) and mixtures thereof, which have relatively low molecular weight and are amorphous. Furthermore, those modified with well-known compounds such as unsaturated carboxylic acids and their esters are also included.

And in the present invention, those softening
Point (value measured by ring and ball method) and melt viscosity (circle)
Measured at 190 ° C with a cone / disk rheometer
Value) must fall within a certain range
It That is, the softening point must be in the range of 100 to 170 ° C.
I have to. If the softening point is lower than 100 ℃, waterproof
The surface of the sheet is sticky and difficult to handle, and it is higher than 170 ℃
And the tackiness is less likely to be expressed, both are not preferable.
Yes. In addition, to prevent the surface of the waterproof sheet from sticking and
In order to ensure the development of
The softening point of α-olefin is in the range of 105 to 155 ° C.
Is more preferable. The melt viscosity is 10^-1
Range of -10 Pascal-seconds (hereinafter abbreviated as "Pa-S")
It is required to be in the range of 1 to 8 Pa · S.
To be If the melt viscosity is lower than 1 Pa · S,
The deterioration of the physical properties of the tarpaulin will be seen,
Especially 10 ^-1Waterproof when the viscosity is lower than Pa · S
The physical properties of the sheet are significantly reduced. And the melt viscosity
If the viscosity is higher than 8 Pa · S, the impregnating property into the fabric will deteriorate.
A tendency is seen, especially when the viscosity becomes higher than 10 Pa · S,
It has a bad influence on the impregnation property of the fabric.

The crystalline poly α-olefin used in the present invention is a well-known compound such as a homopolymer of α-olefins or a copolymer thereof, and further these unsaturated carboxylic acids and their esters. It is a modified product of the above and has crystallinity such as having a definite melting point. Of course, a mixture of two or more of these may be used. Specific examples include high-density polyethylene,
Examples include isotactic polypropylene and crystalline ethylene / propylene copolymers (crystalline ethylene / propylene random copolymers, crystalline ethylene / propylene block copolymers, etc.). There are no particular restrictions on the molecular weight, chemical composition, melt viscosity, etc. of these crystalline poly-α-olefins, and the amorphous poly-α-olefins to be used are not limited.
It should be appropriately selected depending on the properties of the olefin and the mixing ratio of the two.

In the present invention, as the α-olefin, there are two kinds of the amorphous poly α-olefin and the crystalline poly α-olefin (however, the crystalline poly α-olefin may not be contained). To use. There is no particular restriction on the selection of both, but in general, a compatible combination is preferable because it is easy to form a uniform matrix. For example, amorphous polypropylene / crystalline polypropylene, amorphous propylene / ethylene copolymer /
Crystalline ethylene / propylene copolymer, amorphous polypropylene / crystalline ethylene / propylene copolymer, amorphous propylene / butene-1 copolymer / crystalline ethylene / propylene copolymer, amorphous propylene / butene -1 copolymer / crystalline polypropylene and the like.

As the carbon black used in the present invention, there are commonly known ones such as channel black, furnace black, thermal black, acetylene black and lamp black. Of these, channel black and furnace black are preferable. The particle size of carbon black is 10 to 30 n
Those of about m are particularly preferable.

Next, one of the important constituent features of the present invention is
It is the mixing ratio of these three. That is, the poly α-olefin composition of the present invention comprises 10 to 100 parts by weight of amorphous poly α-olefin, preferably 20 to 80 parts by weight, particularly preferably 30 to 70 parts by weight, and crystalline poly α-olefin.
90 to 0 parts by weight of olefins, preferably 80 to 20
Parts by weight, particularly preferably 70 to 30 parts by weight (however, the total amount of the amorphous poly α-olefin and the crystalline poly α-olefin is 100 parts by weight), and the carbon black is 1 to 5 parts by weight, preferably 1 to 3 parts by weight. If the blending ratio of the amorphous poly α-olefin is less than 10 parts by weight, the workability of the waterproof sheet, which is the object of the present invention, in particular, the bondability cannot be sufficiently expected, and it cannot be put to practical use. Further, if the amount of carbon black is less than 1 part by weight, the weather resistance and the colorability are deteriorated, which is not preferable.
The effect cannot be expected to be improved by adding more than 5 parts by weight. And, in order to surely suppress the occurrence of these unfavorable phenomena, the amounts of the amorphous poly α-olefin, the crystalline poly α-olefin and the carbon black should be in the above-mentioned preferable range, and further particularly preferable range. Is. In addition,
In the present invention, various known additives, modifiers, fillers and the like may be added in addition to the above-mentioned three components as long as the effect thereof is not impaired. Particularly when weather resistance is required, it is desirable to use an ultraviolet absorber or a combination thereof with an antioxidant in combination. In this case, as the ultraviolet absorber and antioxidant to be used, known ones usually used for polyolefins are suitable.

The poly α-olefin composition comprising the amorphous poly α-olefin, the crystalline poly α-olefin and the carbon black is produced by using a known apparatus. That is, it can be achieved by melting and kneading the three using an apparatus such as a Banbury mixer, a super mixer, a mixing roll, a twin screw continuous mixer, a Brabender plastograph, a kneader, a single screw extruder, a twin screw extruder. In this case, the kneading method is not particularly limited, but a method of preparing and using a master batch of carbon black is generally used in order to improve the dispersibility of minute carbon black. The melt-kneading is performed at a temperature of 180 to 250 ° C, preferably 190 to 230 ° C. If the melt-kneading temperature is lower than 180 ° C., the melt viscosity of the amorphous poly α-olefin and the crystalline poly α-olefin becomes too high and a part of these poly α-olefin solidifies in the kneading device. As a result, the poly-α-olefin and carbon black are not sufficiently kneaded. Further, if the temperature is higher than 250 ° C., thermal decomposition or thermal deterioration of these poly α-olefins occurs, which causes coloring or deterioration of physical properties, which is not preferable.

In the present invention, a woven fabric is impregnated with the poly α-olefin composition obtained as described above, and as the fibers forming the woven fabric used in the present invention, well-known glass is used. In addition to fibers, various organic polymer fibers such as polyethylene terephthalate fiber and vinylon fiber are typical. These are usually used alone, but a combination of two or more of them may be used. The diameter of these fibers is not particularly limited, and generally the diameter is about 4 to 20 μm. The number of the above fibers to be used is not particularly limited, either, but is 100 to 12
About 00 tex (grams per 1000 m) is preferable. When it is less than 100 tex, the tear strength of the resulting waterproof sheet is low, and when it is more than 1200 tex, the impregnation property of the resin into the woven fabric is not good. In addition, in order to improve the wettability and the adhesiveness with the above-mentioned poly α-olefin composition serving as a matrix and to enhance its reinforcing effect, that is, the mechanical strength, the fiber has a surface treatment agent (silane coupling). Agent) is usually applied.

There is no particular limitation on the structure of the fabric used in the present invention. That is, there is no restriction on the weaving density in the practice of the present invention, and the warp yarn and the weft yarn are 5 to 30 yarns / 2.
About 5 mm is sufficient. The yarn counts of the fibers used for the warp yarns and the weft yarns described above, and the weaving densities of both of them are points of the isotropic tear strength of the obtained waterproof sheet (that is, the tear strengths in the warp direction and the weft direction are equal). Therefore, it is preferable that they are the same, but the present invention is not necessarily limited thereto. There is no particular designation for the woven structure of the fabric used in the present invention, and plain weave, satin weave,
Well-known ones such as twill can be mentioned, but plain weave is most preferable.

Impregnation of the woven fabric with the poly-α-olefin composition can be carried out by a known method. For example, a method of emulsifying a poly α-olefin composition with an emulsion or a solution of an organic solvent such as P-xylene, toluene, and decalin and impregnating the woven fabric, and then removing water and the solvent by drying, a poly α-olefin composition A film or sheet by a known means such as film or sheet extrusion molding, calender roll processing, press sheet processing, etc., and a method of impregnating by laminating with a woven fabric by heating, melting and pressing, a poly α-olefin composition. Preferable examples include a method of impregnating by heating, melting and pressing after being introduced into a woven fabric in a powder form or a fibrous form, a method of superposing a molten sheet of a poly α-olefin composition and a woven fabric, and impregnating under pressure. To be In this case, it is also effective to appropriately perform operations such as preheating, deaeration, and fiber opening on the woven fabric in order to perform good impregnation. In the various impregnation methods described above, the case where the number of fabrics used is one is the simplest case, but it is also possible to use a fabric having two or more layers.

Ease of handling and flexibility in joining the waterproof sheet thus produced or attaching it to a base material, and productivity in producing the waterproof sheet (ease of impregnation). Considering the above, the width of the waterproof sheet is 2
Typical examples are shapes having a thickness of 00 to 1000 mm and a thickness of 0.5 to 2 mm.

On the other hand, as the composition of the waterproof sheet, the poly α-olefin composition is 50 to 85% by volume, preferably 60 to 80% by volume, and the woven fabric is 50 to 15% by volume, preferably 40 to 20% by volume. % (However, the above poly α
The olefin composition and the fabric are generally composed of 100% by volume). The content of the fabric is 15
When it is less than the volume%, the mechanical strength and rigidity of the waterproof sheet are not improved. Further, when the content of the woven fabric exceeds 50% by volume, that is, when the content of the poly α-olefin composition is less than 50% by volume, the joining property of the waterproof sheet based on the amorphous poly α-olefin is obtained. Is not sufficient and impregnation of the fabric with the poly-α-olefin composition is insufficient, which is not preferable. When the content of the woven fabric and the content of the poly α-olefin composition deviates from the preferable range described above, the above-described unfavorable phenomenon may occur in the obtained waterproof sheet.

As described above, since the waterproof sheet obtained by the present invention has a low melt viscosity of the impregnated poly-α-olefin composition, it does not require a particularly large force (pressure) in a short time. Also join the tarpaulin comrades,
It can be easily attached to the base and integrated. In this case, the tarpaulin is impregnated with poly α-
It is necessary to heat to near the melting start temperature of the olefin composition.

[0021]

The present invention will be described in more detail with reference to examples and comparative examples, but these do not limit the present invention.

In the following examples and comparative examples, the poly α-olefin composition used and the physical properties of the woven fabric are as follows.
It was measured by the following method. (1) Softening Point of Amorphous Poly α-Olefin It was measured according to ASTM E28 using a ring and ball softening point tester.

(2) Melt Viscosity of Amorphous Poly α-Olefin A cone / disk type rheometer (mechanical spectrometer manufactured by Rheometrics Co., Ltd.) was used, and ASTM D3 was used.
Measured according to 236 at 190 ° C.

(3) Melt Flow Index of Crystalline Poly α-Olefin The melt flow index was measured at 230 ° C. according to ASTM D1238 using a melt indexer.

(4) Weight of woven fabric According to JIS L1096, the weight of a woven fabric of 20 cm × 20 cm was weighed to determine the weight per 1 m ² .

(5) Fabric Thickness The fabric thickness was measured using a dial gauge micrometer in accordance with JIS L1096.

The evaluation method of the waterproof sheet adopted in these Examples and Comparative Examples is as follows. (A) Fiber volume fraction (V _f ) According to JIS K7052, it was determined by thermally decomposing the resin component.

(B) Bondability According to JIS A6008, the bonding state was evaluated, and it was judged whether the sample was broken at the bonded portion or the adherend portion. However, the joining operation is performed by using a press at 170 ° C.
It was performed by a method of pressurizing at 0.35 MPa (gauge pressure) for 1 minute.

(C) Tear strength According to the trouser tear method described in JIS K7128,
The tear load (maximum load) was determined and the value divided by the thickness of the sample was taken as the tear strength (N / mm). The measurement was made in the warp direction and the weft direction of the woven fabric, and the average value thereof was adopted.

Example 1 Amorphous propylene / butene-1 copolymer (trade name: UBETAC APAO UT27 manufactured by Ube Lexen Co., Ltd.)
15, softening point: 107 ° C, melt viscosity: 1.5 Pa · S)
50 parts by weight, crystalline polypropylene (Ube Industries, Ltd.)
Made, product name: UBE polypro J130G, melt flow index: 30 g / 10 minutes) 50 parts by weight and carbon black (manufactured by Mitsubishi Kasei Co., Ltd., product name: Mitsubishi carbon black MA600, particle diameter: 18 nm) 2 parts by weight The pellets were produced by melt-kneading at 200 ° C. using a twin-screw extruder. However, as the carbon black, the masterbatch pellet of the crystalline polypropylene (carbon black content: 10% by weight) was used. Next, the pellets were press-molded at 170 ° C. and 0.5 MPa (gauge pressure) for 1 minute to obtain a film having a thickness of 200 μm (measured with a dial gauge micrometer).

Therefore, this film and glass fiber fabric (manufactured by Nitto Boseki Co., Ltd., trade name: glass cloth WL 410)
N-105, basis weight: 410 g / m ² , thickness: 400
μm, texture: plain weave), 170 ° C, 0.6
Press-molded with MPa (gauge pressure) for 2 minutes, 20 cm x
A waterproof sheet having a width of 20 cm and a thickness of 670 μm (note that the width and length of the waterproof sheet refer to steel products, and the thickness of the waterproof sheet was measured using a digital micrometer. The same applies below). Table 1 shows the evaluation results of this waterproof sheet.

Examples 2 to 4 Instead of the glass fiber fabric of Example 1, glass fiber fabric (manufactured by Nitto Boseki Co., Ltd., trade name: Glass Cloth WS 520)
G-100, weight per unit area: 465 g / m ² , thickness: 400
μm, texture: plain weave (in the case of Example 2), the same (manufactured by Nitto Boseki Co., Ltd., trade name: glass roving cloth WR 57
0C-100, weight per unit area: 570 g / m ² , thickness: 50
0 μm, texture: plain weave (in the case of Example 3) or the same (manufactured by Nitto Boseki Co., Ltd., trade name: glass cloth WL 230N-
28 N, basis weight: 210 g / m ² , thickness: 240 μ
m, texture: plain weave) (in the case of Example 4) except that the waterproof sheet obtained by the same treatment as in Example 1 is evaluated is shown in Table 1.

Examples 5, 6 and Comparative Example 1 Instead of the amorphous propylene / butene-1 copolymer of Example 1, an amorphous propylene / butene-1 copolymer (manufactured by Ube Lexen Co., Ltd., Product Name: UBETAC APAO
UT2780, softening point: 110 ° C, melt viscosity: 8 Pa
S) (in the case of Example 5) or an amorphous propylene / ethylene copolymer (manufactured by Ube Lexen Co., Ltd., trade name: UBE
TAC APAO UT2535, softening point: 129 ° C,
Melt viscosity: 3.5 Pa · S) (in the case of Example 6) or no amorphous poly α-olefin was used (in the case of Comparative Example 1), except that Example 1 was used. Table 1 shows the evaluation results of the waterproof sheet obtained by treating in exactly the same manner.

Examples 7 and 8 Ratio of amorphous propylene / butene-1 copolymer to crystalline polypropylene in Example 1 (50 parts by weight: 50)
70 parts by weight: 30 parts by weight (in the case of Example 7) and 30 parts by weight: 70 parts by weight (Example 8).
Table 1 shows the evaluation results of the waterproof sheet obtained by performing the same treatments as in Example 1 except that the above case was used.

Example 9 The resin film obtained in Example 4 before being laminated with the glass fiber woven fabric and the glass fiber woven fabric used in Example 4 were alternately laminated on four sheets at 160 ° C. 0.5
Press molding at 1 MPa (gauge pressure) for 1 minute, 20 cm x
A waterproof sheet having a thickness of 20 cm and a thickness of 670 μm was obtained. Table 1 shows the results of the same evaluations as in Example 4 performed on these waterproof sheets.

[0036]

[Table 1]

[0037]

As is clear from the examples and comparative examples described above, the waterproof sheet provided by the present invention has high tear strength and excellent bondability, and thus has a good balance of physical properties and workability. It is a material. Furthermore, poly α-
Since it is composed of an olefin matrix, it has essentially good water resistance and chemical resistance. Therefore, it can be used as a sheet-like waterproof material that can be used not only for construction but also for civil engineering.

Claims (1)

[Claims] 1. A softening point of 100 to 170 ° C.,
And 10 to 100 parts by weight of an amorphous poly α-olefin having a melt viscosity of 10 ⁻¹ to 10 Pascal · second at 190 ° C., (2) 90 to 0 parts by weight of a crystalline poly α-olefin, and (3 ) It is obtained by impregnating a woven fabric with a poly α-olefin composition comprising 1 to 5 parts by weight of carbon black (however, the total amount of the amorphous poly α-olefin and the crystalline poly α-olefin is 100 parts by weight). Characteristic waterproof sheet.