JPS63178183A - Adhesive composition for waterproof smeet - Google Patents

Abstract

PURPOSE:To provide the title compsn. which has excellent applicability and good alkali resistance and can be used as an adhesive for use in bonding waterproof sheets to each other or a waterproof sheet for the surface of concrete, by incorporating an ultra vulcanization accelerator in a specified rubber mixture. CONSTITUTION:An adhesive compsn. for waterproof sheets consists of 85-30pts. wt. butyul rubber, halogenated butly rubber or polyisobutylene (A), 15-70pts.wt. natural rubber or isoprene rubber (B) and 5-40pts.wt. ultravulcanization accelerator (C) (e.g., zinc dimethyldithiocarbamate). The adhesive compsn. exhibits sufficient adhesion by simple coating on a substrate without the need of applying any primer which must be used for conventional adhesives. Further, the compsn. can keep high adhesion under alkaline conditions and has high-temperature adhesion. The compsn. can be used as an adhesive for use in bonding waterproof sheets to each other or a waterproof sheet to the surface of concrete and is suitable for use as an adhesive for roofing materials and waterproof materials form civil engineering works for ponds, pools, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an adhesive for a waterproof sheet, and more particularly to an adhesive composition for a waterproof sheet that has excellent workability and good alkali resistance.

[Prior art]

Tarpaulin sheets are widely used as rooftop roofing materials or waterproof materials for civil engineering, among others, ethylene and
Vulcanized rubber sheets containing propylene terpolymer (EPT) as a main component are particularly widely used because of their excellent durability and strength.

Conventionally, chloroprene-based solvent-based adhesives have been used as adhesives for such waterproof sheets, but because they have low alkali resistance, they are easily damaged when rainwater enters through nail holes or poor adhesion at sheet seams. This method has the disadvantage that it tends to peel off, and it also has the problem of poor workability because it requires the use of a primer in the adhesive method and the need to apply adhesive to both the base and the waterproof sheet side.

[Purpose of the invention]

An object of the present invention is to provide an adhesive composition for a waterproof sheet that has excellent workability and good alkali resistance. This adhesive composition is particularly used as an adhesive between waterproof sheets or between a waterproof sheet and a concrete or mortar surface.

[Structure of the invention]

Therefore, the present invention provides a waterproof sheet comprising 85 to 30 parts by weight of butyl rubber, halogenated butyl rubber, or polyisobutylene rubber, 15 to 70 parts by weight of natural rubber or isoprene rubber, and 5 to 40 parts by weight of a supervulcanization accelerator. The gist of this paper is an adhesive composition.

Hereinafter, the configuration of the present invention will be explained in detail.

(85 to 3 oit parts of 11 butyl rubber, halogenated butyl rubber, or polyisobutylene rubber.

Examples of the halogenated butyl rubber include chlorinated butyl rubber and brominated butyl rubber. Considering compatibility with natural rubber, it is preferable to use halogenated butyl rubber rather than butyl rubber. The amount of butyl rubber, halogenated butyl rubber or polyisobutylene rubber is 1 for the total rubber.
It is 85 to 30 parts by weight out of 00 parts by weight. If the amount exceeds 85 parts by weight, the butyl rubber or polyisobutylene rubber will be softened at high temperatures, and the heat resistance will not improve. Also,
If it is less than 30 parts by weight, the adhesive force will decrease and the peel strength will deteriorate, so it is preferably 85 to 30 parts by weight.

(2) 15 to 70 parts by weight of natural rubber or isoprene rubber.

Either natural rubber or isoprene rubber may be used. The blending amount is 15 to 70 parts by weight out of 100 parts by weight of the total rubber content.

(3) 5 to 40 parts by weight of super vulcanization accelerator.

The super vulcanization accelerator used in the present invention is one that rapidly accelerates the vulcanization of natural rubber or isoprene rubber at room temperature, and examples thereof include zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, zinc dibutyldithiocarbamate, and dimethyldithiocarbamate. Sodium, metal salts of dithiocarbamates such as sodium diethyldithiocarbamate, metal salts of xanthocarbamates such as zinc butylxanthogenate, zinc isoprobylxanthogenate, sodium isoprobylxanthogenate, 2-mercaptobenzothiazole, dibenzothiazyl disulfide, etc. Examples include thiazole-based vulcanization accelerators. The blending amount is 5 to 40 parts by weight per 100 parts by weight of the total rubber, and the blending amount is 5 to 40 parts by weight.
If the amount is less than 1 part by weight, the vulcanization rate will be slow and the heat resistance will be poor. Moreover, if the amount exceeds 40 parts by weight, the cohesive force decreases, resulting in brittleness and insufficient adhesive force.

In the present invention, sulfur is used as a vulcanizing agent for natural rubber or isoprene rubber. It is preferable to use about 2 parts by weight of sulfur per 100 parts by weight of natural rubber or isoprene rubber.

Further, in the present invention, a solvent is blended.

As the solvent used, one is selected that is highly soluble in butyl rubber, halogenated butyl rubber, polyisobutylene rubber, natural rubber, and isoprene rubber. Examples include aromatic hydrocarbons such as benzene, toluene, and xylene, and aliphatic hydrocarbons such as n-octane, and these solvents may be used alone or as a mixed solvent of two or more. The amount of these solvents used is determined when the solid content of the adhesive composition is 2.
The content is adjusted to 0 to 30% by weight.

Furthermore, in the present invention, various fillers can be added to the rubber composition. For example, it is possible to mix inorganic fillers such as carbon black, metal oxides, calcium carbonate, talc, and silica, and zinc white as a vulcanization aid to prevent sagging and reduce costs. Additionally, tackifiers and the like can also be used to provide initial adhesive strength. For example, rosin and rosin derivatives, terpene resins, aliphatic hydrocarbon resins, aromatic petroleum resins, and the like are effective.

Examples and comparative examples are shown below.

1-7, 1-3 Chlorinated butyl rubber (chlorobutyl rubber 1066, Exxon Chemical), butyl rubber (Essobutyl 264, Exxon Chemical), polyisobutylene rubber (Vesta-nex MML) with the compounding contents (parts by weight) shown in Table 1 below. −
100, Exxon Chemical) and natural rubber (RSS#1) or isoprene rubber, Ball IR-2200, Nippon Zeon), sulfur, and carbon black (MA600, Mitsubishi Chemical Industries) are kneaded with a roll, and then zinc dibutyldithiocarbamate ( Tsukusela BZ, Iriuchi Shinko Kagaku Kogyo) and zinc white were added and dissolved in toluene to make an adhesive.

Adhesion conditions: Here, a vulcanized rubber sheet (varnish sheet, manufactured by Shibata Industries) whose main components are EPT and butyl rubber is used as the waterproof sheet, and the rubber sheets are bonded to each other or the waterproof sheet and the slate board (
An adhesion test was conducted between JIS A 5043 (F)). The surface of the vulcanized rubber sheet was used without being particularly treated with a solvent or the like. Apply 350 g/n of adhesive to the slate board or rubber sheet on the adherend side using a spatula. After approximately 15 minutes of open time, rubber sheets were pasted together and pressed together with a hand roller, and after being left at room temperature for one week, an adhesive force measurement test was conducted.

Measurement test; ■Normal peel strength.

Measurement was carried out under the conditions of a peeling angle of 180', a peeling rate of 200 mm/min, and a measurement temperature of 25°C.

■Alkali peel strength.

After 4 days of immersion in a 1% solution of NaOHO saturated with Ca (OH) 2 , it was dried for 4 hours, and then measured according to the above ①.

■High temperature peel strength.

After being left in a constant temperature bath at 60° C. for 10 minutes, measurements were taken according to the above procedure (①).

The above results are shown in Table 1. For comparison, similar tests were conducted on commercially available chloroprene adhesives, and those using chlorinated butyl rubber and natural rubber, whose formulations are shown in Table 1, alone, and the results are shown. From Table 1, it can be seen that Examples 1 to 7 are superior to Comparative Examples 1 to 3.

(Margins below this page) Chlorinated butyl rubber (Chlorobutyl Rubber 1066, Exxon Chemical Company) with the formulation content (parts by weight) shown in Table 2 below.
After kneading with a roll, natural rubber (RSS Jll), sulfur, and carbon black (MA600, Mitsubishi Chemical Industries), zinc white and zinc dibutyldithiocarbamate (Tsukusela BZ, Iriuchi Shinko Kagaku Kogyo) or zinc dimethyldithiocarbamate (Tskusela PZ, Irinai Shinko Kagaku Kogyo) and 2-mercaptobenzothiazole zinc salt (Tsukusela MZ, Iriuchi Shinko Kagaku Kogyo) were added and dissolved in toluene to form an adhesive. The adhesive strength between the vulcanized rubber sheet and the slate plate was measured in the same manner as in Example 1. The results are shown in Table 2.

(Margins below this page) Table 2 Note) *Tsukuseller BZ This chapter Tsukseller PZ To this city rate Tsukseller [Effects of the invention] As explained above, the adhesive composition of the present invention does not require the use of a primer like conventional products. The bonding method is not complicated, and sufficient adhesive strength can be obtained by simply applying the adhesive to the base side. Furthermore, it maintains high adhesive strength even in alkali, so it has excellent alkali resistance on mortar surfaces, concrete surfaces, etc.

In addition, rooftop surfaces can reach temperatures of 50 to 60 degrees Celsius in midsummer, and since they have a certain degree of heat-resistant adhesive strength even at such temperatures, they can be used as rooftop roofing materials or in civil engineering works such as ponds and swimming pools. It has the advantage that it can be effectively used as an adhesive for waterproof materials.

Claims (1)

[Claims] An adhesive composition for a waterproof sheet comprising 85 to 30 parts by weight of butyl rubber, halogenated butyl rubber, or polyisobutylene rubber, 15 to 70 parts by weight of natural rubber or isoprene rubber, and 5 to 40 parts by weight of a supervulcanization accelerator.