JP2000073045A - Sealing material for waterproofing sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain sealing material for a waterproofing sheet capable of closely adhering to a joining section between waterproofing sheets each comprising a polyolefin resin or olefin-based thermoplastic elastomer and of retaining the desirable properties. SOLUTION: This sealing material 3 for a waterproofing sheet is applicable to a joining section between waterproofing sheets 1 and 2 each comprising a polyolefin resin or olefin-based thermoplastic elastomer, and mainly comprises a styrene-olefin-styrene block copolymer as a composition. The copolymer comprises 10 to 30% of styrene and 90 to 70% of olefin, and the olefin is at least one selected from the group consisting of ethylene-propylene copolymer, ethylene-butylene copolymer and hydrogenated product of polybutadiene.

Description

DETAILED DESCRIPTION OF THE INVENTION

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing material composition disposed at a joint of a waterproof sheet, and more particularly to a waterproof sheet made of a polyolefin resin or an olefin-based thermoplastic elastomer sheet excellent in environmental problems and recyclability. The present invention relates to a sealing material that is arranged at a joint portion and seals.

[0002]

2. Description of the Related Art A waterproof sheet made of resin or rubber is generally laid on a roof of a building, a reservoir, a waste disposal site, or the like for the purpose of waterproofing. Examples of the waterproof sheet material include rubber, vinyl chloride resin, and polyethylene resin, but the rubber sheet is disadvantageous in terms of labor saving and energy saving in sheet production, and recyclability, and the vinyl chloride resin is also dehalogenated. There is a problem in terms of environmental problems. In that regard, the above-mentioned polyolefin resins such as polyethylene and olefin-based thermoplastic elastomers can be said to be advantageous materials in terms of recyclability without a problem of affecting the surrounding environment.

On the other hand, in a waterproof sheet, a sealing material is sometimes applied to a joint portion thereof in order to further improve watertightness. The sealing material is disposed on the end face of the waterproof sheet overlapping the upper portion of the joint portion. In particular, when a base fabric such as glass fiber or polyester fiber is buried in the waterproof sheet, the presence of a seal is also important in order to prevent water impregnation from the base cloth portion in the thickness section of the waterproof sheet. . Therefore, a silicone rubber-based, polysulfide-based, or polyurethane-based sealant is generally used as such a sealant.

[0004]

However, as a characteristic usually required as a sealing material, it is necessary to ensure sufficient watertightness at a joint portion to prevent water leakage. Be able to adhere to the waterproof sheet with sufficient strength. Have long-term weather resistance. The loss of surface tackiness over time to prevent contamination. The solid content is high and the meat does not lose weight over time. Low viscosity and excellent workability when applying sealing material. However, the current sealing materials cannot sufficiently exhibit the sealing effect when a sheet made of the polyolefin resin or a waterproof sheet made of the olefin-based thermoplastic elastomer is used.

[0005] Such a material such as a polyolefin resin or an olefin-based thermoplastic elastomer is a non-polar, chemically very inactive polymer, and therefore is extremely poor in terms of adhesiveness. Adhesives currently in use cannot adhere firmly to the substrate, and fixing between the waterproof sheet and the substrate can be done by driving an anchor member or the like into the substrate from above the waterproof sheet, or by using the same material. In this state, the waterproof sheet is locally physically fixed by fixing the plate to an underlayer with an anchor or the like and bonding the waterproof sheet to the plate by welding or fusion.

[0006] As with the adhesive, the silicone rubber-based, polysulfide-based, or polyurethane-based sealant, which is currently used, is made of a polyolefin resin or an olefin-based thermoplastic elastomer. Cannot be bonded to a waterproof sheet.

Accordingly, the present invention addresses the above-mentioned problems and finds a particularly effective composition to have sufficient adhesiveness to a polyolefin resin or a waterproof sheet using an olefin-based thermoplastic elastomer. It is another object of the present invention to provide a sealing material composition having a sealing property satisfying the above-mentioned required properties.

[0008]

That is, in the basic invention according to the first aspect, the sealing material composition of the present invention that meets the above-mentioned object is applied to the joint of a waterproof sheet made of a polyolefin resin or an olefin-based thermoplastic elastomer. The sealing material for a waterproof sheet to be used is mainly composed of a styrene-olefin-styrene block copolymer.

This feature is based on the fact that a composition containing a styrene-olefin-styrene block copolymer as a main component is used as a sealing material, and water sealing, weather resistance, high solid content, viscosity, loss of tackiness, etc. It has the properties required for a sealing material and can be firmly bonded to a thermoplastic elastomer, and is suitable as a sealing material for a waterproof sheet made of a thermoplastic elastomer.

In the invention according to claim 2, the styrene content of the styrene-olefin-styrene block copolymer, which is the main component of the sealing material composition, is in the range of 10 to 30% and the olefin content is in the range of 90 to 70%. And With such a ratio, the viscosity of the sealing material can be kept in an appropriate range, and the adhesiveness with the waterproof sheet made of an olefin-based thermoplastic elastomer can be improved by setting the styrene content in an appropriate range. can do.

In the invention according to claim 3, the olefin of the block copolymer used as the sealing material composition is at least one selected from the group consisting of ethylene propylene copolymer, ethylene-butylene copolymer and hydrogenated polybutadiene. It is characterized by being a seed. By using one of the above three types of olefins, the sealing material can have an appropriate hardness and an appropriate rubber elasticity.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described in detail.

FIG. 1 is a cross-sectional view showing a state in which a waterproof sheet sealing material of the present invention is applied to a joint of a waterproof sheet.

In FIG. 1, 1 and 2 are waterproof sheets,
The two waterproof sheets 1 and 2 are bonded together by heat fusion or an adhesive, and a seal is provided from the end face of the waterproof sheet 2 arranged on the upper side of the laminated waterproof sheet to the lower waterproof sheet 1 on the lower side. Material 3 has been applied.

The material of the waterproof sheets 1 and 2 used in the present invention is a waterproof sheet made of a polyolefin resin or an olefin thermoplastic elastomer. Examples of the polyolefin resin include high-density polyethylene, medium-density polyethylene, low-density polyethylene, and polypropylene.As the olefin-based thermoplastic elastomer, polyethylene or polypropylene and ethylene propylene rubber are blended with the polyolefin resin, or both are monomer-based. It is a copolymerized material that has both properties of resin and rubber.

As specific examples of the olefin-based thermoplastic elastomer, TPR (trade name, manufactured by Uniroyal),
Telcar (BF Goodrich Chemical
al), Somel (Dupont), TPO (E
xxon Chemical Co., Ltd.) and Esplen (Sumitomo Chemical Co., Ltd.).

It is difficult to bond the waterproof sheets 1 and 2 made of these materials to each other with a commonly used adhesive, and is often performed by heat fusion.
A method in which the joining surfaces are melted by blowing hot air onto each other and rolled together to perform heat fusion is usually employed. However, it is also possible to bond with an adhesive, and it is possible to bond using a naturally vulcanized type butyl rubber-based tape adhesive by applying a primer mainly composed of chlorinated polypropylene. . The chlorinated polypropylene used for this primer has a CL content of 1
It is preferable to use 5 to 40%. Also,
An epoxy resin having an epoxy equivalent of 200 ± 50 g / eq is added to the chlorinated polypropylene in an amount of 1 to 10 parts by weight based on 100 parts by weight of the chlorinated polypropylene in order to prevent deterioration with time.
Contains parts by weight. By adding an epoxy resin, it is possible to prevent the chlorinated polypropylene from deteriorating with time, and to prevent a decrease in adhesive strength.

Further, in order to improve the adhesiveness with a butyl rubber-based tape adhesive, rosin ester, aliphatic,
An alicyclic or aromatic petroleum resin, a coumarone indene resin or the like can be blended in an amount of 5 to 8 parts by weight based on 100 parts by weight of the chlorinated polypropylene. The natural vulcanized adhesive tape containing butyl rubber as a main component is a mixture of butyl rubber or halogenated butyl rubber (chlorinated or brominated) and one or two types of ethylene propylene diene rubber and isobutylene. Mooney viscosity of ML1 + 8
(100 ° C.) is preferably in the range of 3 to 25.
When the initial Mooney viscosity ML1 + 8 (100 ° C.) is less than 3, there is also a problem that the bonding operation is difficult due to the softness, and the initial adhesiveness is insufficient.

As the vulcanizing agent, those generally used in combination with an accelerator such as tyrium or dithiocarbamate, or those in which peroxide and its accelerator are blended can be used. In addition, a tackifier, a plasticizer, and a process oil for improving the self-adhesion of the tape may be blended. Aliphatic, alicyclic and aromatic petroleum resins, as well as compatible resins such as rosin and phenolic resins, or plasticizers such as dioctyl phthalate, dibutyl phthalate and dioctyl adipate, and paraffinic and naphthenic processes Fillers such as carbon black, calcium carbonate, silica, talc, clay and the like can be blended as necessary as a reinforcing agent in order to increase the cohesive force of the oil and the adhesive.

Next, the sealing material 3 applied to the joining portion to be joined as described above is made of the sealing material composition of the present invention, and is one or more of a styrene-olefin-styrene block copolymer. As a main component. As the olefin part of the copolymer, at least one selected from the group consisting of ethylene-propylene copolymer, ethylene-butylene copolymer, and hydrogenated butadiene is preferably used.

The use of at least one of these three types of olefins has the advantage that a sealing material having rubber elasticity and appropriate hardness can be obtained. In addition, the SP value of a polyolefin resin or an olefin-based thermoplastic elastomer can be obtained. (Solubility constant), so that the adhesion to the waterproof sheet is improved. Usually, the SP value of a polyolefin resin or an olefin-based thermoplastic elastomer is about 7.9, so that about 7.6 to 8.3 is suitable for use as a sealing material.

The copolymer has a styrene content of 10 to 30%.
Is a block copolymer having an olefin content of 90 to 70%, a hardness of 40 to 80 ° in Shore A, and an MFR of
(ASTM D1238) 3.5-13.0 g / 1
When the styrene content is less than 10% and the olefin content is more than 90%, the styrene content cannot be dissolved in a solvent such as toluene. It becomes too high and unsuitable for practical use. Generally speaking, the viscosity suitable for a sealing material is about 1,000 to 10,000 cps,
If it is less than cps, it will flow too much, and if it exceeds 10,000 cps, the surface flow property will deteriorate, which is not preferable. Therefore, the styrene content is preferably more than 10% so that the viscosity does not become too high. On the other hand, styrene content is 30%
If the olefin content exceeds 70% and is less than 70%, it is not preferable because sufficient adhesion to a waterproof sheet made of a polyolefin resin or an olefin-based thermoplastic elastomer cannot be ensured.

In addition to the above, in order to improve the workability by adjusting the hardness to a suitable level, the sealant has good affinity for a waterproof sheet made of a polyolefin resin or an olefin-based thermoplastic elastomer.
Fillers such as calcium carbonate, silica, talc, carbon black, clay, etc. as a reinforcing material to increase the cohesive force of the sealant and eliminate the stickiness over time to prevent contamination, such as hexane, etc. For the purpose of improvement, tackifiers such as alicyclic or aromatic petroleum resins or phenolic resins, plasticizers such as dioctyl phthalate, dibutyl phthalate, dioctyl adipate, and softeners such as paraffinic and naphthenic process oils. Can be added. Further, antioxidants, ultraviolet absorbers, light stabilizers and the like can be used to prevent deterioration.

[0024]

EXAMPLES Hereinafter, the effects of the present invention will be confirmed with reference to Examples of the present invention and Comparative Examples. (Example 1) 200.6 parts of toluene was charged into a dissolving machine,
A styrene-ethylene-propylene-styrene block copolymer (SEP) in which the styrene content is 23% and the olefin portion is an ethylene-propylene copolymer while stirring.
100 parts by weight of S), 0.3 parts by weight of an antioxidant, 0.2 parts by weight of an ultraviolet absorber, and 0.1 parts by weight of a light stabilizer are added in this order, and stirring is continued for 24 hours. An intermediate was obtained. The viscosity was 6500 cps / 30 ° C.

Next, a 10% toluene solution of SEPS in 10%
A solution prepared by previously mixing 0 parts by weight, 20 parts by weight of light calcium carbonate, and 30 parts by weight of titanium oxide was dispersed by a ball mill for 24 hours to prepare a filler dispersion. This filler dispersion had a solid content of 40% and a viscosity of 250 cps / 30 ° C. After 20 parts by weight of the filler dispersion was blended with 100 parts by weight of the 50% SEPS intermediate, the mixture was uniformly dispersed with a mixer for 1 hour to obtain a sealing material shown in Table 1.

Example 2 A styrene-ethylene-butadiene-styrene block copolymer having a styrene content of 28% was used as a main component of a sealing material composition, and an alicyclic petroleum resin was used instead of an aliphatic petroleum resin. A sealing material was prepared in the same manner as in Example 1 except that phenol resin and dioctyl phthalate were used.

Example 3 A hydrogenated styrene-butadiene-styrene block copolymer having a styrene content of 10% was used as a main component of a sealing material, and an alicyclic petroleum resin and dioctyl phthalate were used instead of an aliphatic petroleum resin. A sealing material was prepared in the same manner as in Example 1 except that was used.

(Comparative Example 1) A styrene-ethylene-butadiene-styrene block copolymer having a styrene content of 33% was used as a main component of a sealing material. Thereafter, a sealing material was prepared in the same manner as in Example 2. Comparative Example 2 Silicon rubber was used as a sealing material. Comparative Example 3 Polysulfide was used as a sealing material. Comparative Example 4 Polyurethane was used as a sealing material.

The compositions, solid contents and viscosities of Examples 1 to 3 and Comparative Example 1 obtained as described above are shown in Table 1, and the sealing materials of Examples 1 to 3 and Comparative Examples 1 to 4 were made of olefin-based heat A waterproof sheet made of a thermoplastic elastomer was bar-coated on top with a thickness of 50 μm, dried at room temperature for 24 hours, further laminated with a waterproof sheet made of an olefin-based thermoplastic elastomer, and cured under the conditions shown in Table 2, 20 ° C 50
A 180 ° peeling test was performed at a speed of mm / min, and the results are shown in Table 2.

[0030]

[Table 1] Below, margins

[0031]

[Table 2]

From the results shown in Table 2 above, when the sealing material composition of the present invention is used, it shows a sufficient adhesive force even to a waterproof sheet made of a polyolefin resin or an olefin-based thermoplastic elastomer. It can be seen that the effect is exhibited.

Looking at Comparative Examples 2 to 4, silicone rubber,
A sealing material using polysulfide or polyurethane hardly provides an adhesive force with a waterproof sheet. Also, from Comparative Example 1, it can be seen that a sealing material using a styrene-ethylene-butadiene-styrene block copolymer having a styrene content of more than 30% cannot provide a long-term adhesive force.

[0034]

As described above, the present invention mainly comprises a styrene-olefin-styrene block copolymer as a sealing material composition used for a joint of a waterproof sheet made of a polyolefin resin or an olefin-based thermoplastic elastomer. Using the composition as a component, water tightness and weather resistance, high solid content, viscosity, such as the loss of tackiness, while having the properties required for the sealing material described above, with respect to the thermoplastic elastomer Can be firmly bonded,
It is extremely suitable as a sealing material for a waterproof sheet made of a thermoplastic elastomer.

The invention according to claim 2 is characterized in that the styrene-olefin-styrene block copolymer, which is the main component of the sealing material composition, has a styrene content of 10 to 30% and an olefin content of 90 to 70%. By adopting such a ratio, the viscosity of the sealing material can be maintained in an appropriate range, and the styrene-based thermoplastic elastomer waterproof sheet can be obtained by adjusting the amount of styrene to an appropriate range. And the adhesiveness with the resin can be improved.

Further, the invention according to claim 3 is characterized in that the olefin of the block copolymer used as the sealing material composition is at least one of ethylene propylene copolymer, ethylene-butylene copolymer and hydrogenated polybutadiene. By using the above three kinds of olefins, there is an advantage that the sealing material can have an appropriate height and an appropriate rubber elasticity.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a state in which a waterproof sheet sealing material according to the present invention is applied to a waterproof sheet joint.

[Explanation of symbols]

 1, 2 tarpaulin 3 Sealing material

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kenzo Iwamoto 4-1-1-21 Hamazoe-dori, Nagata-ku, Kobe Within Mitsuboshi Belt Co., Ltd. (72) Inventor Tsuneo Kubo 4--11 Gakugaoka, Tarumizu-ku, Kobe-shi No. 31 F term (reference) 4H017 AA03 AB07 AB17 AC02 AC04 AD06 AE05

Claims (3)

[Claims] 1. A sealing material for a waterproof sheet used for a joint portion of a waterproof sheet made of a polyolefin resin or an olefin-based thermoplastic elastomer, wherein the sealing material comprises a styrene-olefin-styrene block copolymer as a main component. Sealing material for waterproof sheet. 2. The waterproofing material according to claim 1, wherein the styrene-olefin-styrene block copolymer, which is a main component of the sealing material for a waterproof sheet, has a styrene content of 10 to 30% and an olefin content of 90 to 70%. Sealing material for sheets. 3. The polyolefin of a block copolymer used as a sealing material for a waterproof sheet is at least one selected from the group consisting of ethylene propylene copolymer, ethylene-butylene copolymer and hydrogenated polybutadiene. The sealing material for a waterproof sheet according to claim 1 or 2. [0001]