JPS5837344B2 - Tomakubou Suizai - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a coating composition for waterproofing concrete structures, etc., and more specifically, the present invention relates to a coating composition for waterproofing concrete structures, etc. The present invention relates to a silk composition for use as a waterproofing agent for paint films, which is curable at room temperature and contains an amine.

Asphalt or urethane-based paint film waterproofing agents are used in waterproofing construction such as cork concrete structures, but the former has disadvantages such as sagging in high temperatures in summer and cracking in low temperatures in winter. Furthermore, the latter has the essential drawback that hot water causes a hydrolysis reaction, which deteriorates the performance of the coating film.

In general, the properties that a paint film waterproofing agent should have are (1) high adhesive strength (2) high flexibility of the paint film (3)
The objective of the present invention is to provide a new coating film waterproofing agent that satisfies these properties. The base material is a liquid chloroprene polymer having a xanthate group represented by the formula ROC-SS (wherein R is a hydrocarbon group having 1 to 12 carbon atoms) and has an average diameter of about 100 millimicrons or less. This is achieved by a composition obtained by blending activated zinc white and/or basic zinc carbonate, a softener, and xylylene diamine as a hardening agent for the polymer.

The composition according to the present invention is cured at room temperature to form a rubber-like elastic body, and this cured product not only retains the advantages of chloroprene rubber such as excellent weather resistance and aging resistance, but also
It has particularly excellent water resistance and chemical resistance, and can be used not only for waterproofing concrete structures, but also for lining industrial water pits, fume pipes, tanks, etc. that require acid and alkali resistance. It has characteristics that make it suitable for use.

The liquid chloroprene-based polymer used in the present invention refers to chloroprene alone or together with a monomer that can be copolymerized therewith and has the formula (ROC-S-)2 (wherein R is a hydrocarbon group having 1 to 12 carbon atoms). It is obtained by polymerization in the presence of a xantogen disulfide compound represented by the following formula, and its molecular weight is usually about 500 to 20,000 and has a xanthate terminal group.

Monomers copolymerizable with chloroprene may be monomers containing at least one CH2C/group. Suitable examples include vinyl compounds such as styrene, methacrylic acid, methacrylic acid alkyl esters, acrylonitrile, etc. 3-bucdiene, isoprene, 2,
Examples include conjugated dienes such as 3-dichloro-1,3-butadiene.

The curing agent for the liquid polymer used in the present invention is limited to xylylene diamine.

It has been known that various amines can be used as curing agents for the polymer, but it has been considered difficult to cure quickly at room temperature and improve the water resistance of the cured polymer with amine curing systems. Ta.

However, by using xylylene diamine as a curing agent and using it in combination with active zinc white and/or basic zinc carbonate with an average particle size of about 100 millimicrons or less, it is possible to significantly accelerate the curing speed of the polymer. discovered that the resulting cured product had excellent water and chemical resistance,
This led to the present invention.

The reason why the amine type of the curing agent is limited in the present invention is mainly based on the effect of improving the surface tackiness, water resistance, and chemical resistance of the cured product.

The xylylene diamine to be used may be isolated as an ortho, meta or para isomer, or a mixture thereof, and the amount used should be at least 5 parts by weight per 100 parts by weight of the polymer. If the amount is too small, the curing speed when curing the polymer at room temperature will be too low to be of practical use.

The preferred range is usually 6 to 10 parts by weight. The activated zinc white and/or basic zinc carbonate used in the present invention act as an auxiliary agent for accelerating amine curing of the polymer, and are essential to the present invention.

As the active zinc white used in the present invention, any zinc white commonly used as a vulcanization accelerator for rubber with an average particle size of about 100 millimicrons or less can be used.

Further, basic zinc carbonate can be used in any powder form that is commonly used as a rubber chemical, and the amount used should be at least 2 parts by weight per 100 parts by weight of the polymer.
A range of 5 to 20 parts by weight is particularly suitable.

If the amount is less than 2 parts by weight, the accelerating effect of the zinc compound on the curing rate of the polymer will be insufficient.

As the softener used in the present invention, any softener can be used as long as it is well miscible with the polymer, reduces the viscosity of the polymer composition through a softening effect, and improves the workability. It is limited to 10 to 150 parts by weight per 100 parts by weight.

If it deviates from this range, the solution viscosity of the paint film waterproofing agent composition cannot be lowered sufficiently, making on-site construction difficult, but it also has the disadvantage of reducing the coating film formation speed and performance of the paint film. arise.

Generally preferred amounts used range from 30 to 100 parts by weight.

Suitable examples of softeners used in the present invention include coal-cour, naphthenic and aromatic petroleum process oils, carboxylic acid esters such as dibutyl phthalate, dioctyl phthalate, and dioctyl sebacate, triphenyl phosphate, and tricresyl phosphate. Examples include phosphoric acid esters such as esters, epoxidized soybean oil, epoxy derivatives such as epoxybutyl stearate, liquid coumaron-indene resins, partially hydrogenated terphenyls, and tar-modified terpene resins. Selected appropriately.

A typical embodiment of the waterproof coating composition obtained according to the present invention is as follows.

That is, component A containing the liquid chloroprene-based polymer, activated zinc white and/or saline zinc carbonate, and optionally a softener;
Immediately before use, a curing agent alone or a component B consisting of a curing agent and a softening agent are mixed to prepare a compound and then applied.

In this case, component A and component B are generally prepared separately in advance and mixed at the construction site.

One of the advantages of the assembly according to the present invention is that it not only has excellent performance as a cured product, but also has a pot life that can be varied over a wide range and is extremely easy to work with on site.

In carrying out the present invention, in addition to the above-mentioned various compounding agents, litharge, magnesia, average particle size 300-7
0 0 mil) Micron-sized zinc white* Metal e
It is possible to incorporate antioxidants such as chemical compounds, hindered phenols, and phenyl-α-naphthylamine, pigments for coloring, small amounts of organic solvents as compound viscosity modifiers, and resins such as epoxy resins and phenolic resins. .

In particular, it is preferable to add a filler.

As fillers, those commonly used as fillers for rubber, such as carbon black, titanium oxide, calcium carbonate, silica, and clay, can be used, including hydrous silicic acid and carbon black, which have the effect of significantly increasing the viscosity of the polymer composition. When using a reinforcing filler such as, the amount is usually 2 to 20 parts by weight per 100 parts by weight of the polymer, which is preferable from the viewpoint of workability in the final assembly.

It is preferable to add the coloring pigment in an amount of about 2 to 5 parts by weight per 100 parts by weight of the polymer.

The thus obtained waterproof coating assembly has excellent adhesion to concrete structures, etc., and the coating formed by curing at room temperature has excellent weather resistance, water resistance, chemical resistance, etc. It also has unique flame retardant properties.

Examples are shown below to further specifically explain the present invention.

All parts and percentages herein are expressed by weight.

In this example, a liquid chloroprene polymer having a terminal xanthate group produced according to the following recipe was used.

Polymerization recipe Chloroprene 92 parts 2,3-
Dichloro-1,3-buta 8 dientluene 50 diisoprobyl xanthogen 8-15 sulfide α,α'-azobis-2,4-di 0.5 methylvaleronitrile polymerization temperature (°C) 40-50 Example 1 25 A liquid chloroprene polymer having a terminal isoprobylsanthate group and having a Prutskfield viscosity measured at ℃ of 9.8 million centipoise was homogeneously blended on a paint mill according to the following formulation. A coating film waterproofing agent was produced by mixing the above and B solution for 3 minutes using an impeller type stirrer.

The obtained coating film waterproofing agent was tested at 20°C according to JISA5.
Changes in needle size over time and basic characteristics of the cured coating film as specified in 754 were measured.

These results are shown in Table 1.

Incidentally, formulation C shows a comparative example in which an amine other than xylylene diamine was used as a curing agent.

From these results, it is clear that the present invention is superior in both workability and performance of the cured product.

Mixing Recipes The test conditions for water resistance, acid resistance and alkali resistance in the following examples are the same as the above conditions.

Example 2 A coating composition was prepared in the same manner as in Example 1 according to the following formulation, and after mixing the two liquids, this was used to line the inner surface of a 15 mm wastewater pit.

This pit is a neutralization tank with a liquid temperature of 20 to 60°C, into which an acidic solution with a pH of 1 to 3 and an alkaline solution with a pH of 12 to 14 are introduced alternately, and is used continuously throughout the year.

The lining thickness is 1.3 mm for the first time, and 1.3 mm at room temperature.
Leave it for 4 hours and apply a second coat of 1.2 on the formed coating film.
I applied it in two coats and ended up with 2.5 coats of paint.

When it was put to practical use as the above neutralization tank one week after coating, no significant changes were observed in practical use after one year of use, as it has excellent resistance to water, acids, and alkalis. There wasn't.

Table 2 shows the results of comparing the physical properties of the coating film in the neutralization tank in use with the original physical properties before use.

Blending recipe Polymer 100 parts Activated zinc white 5 Liquid A 77l''-20 SRF carbon black 5 Epoxy resin* 6 Tar 2
0 (Company) *Epikote 828 (manufactured by Mitsubishi Yuka) was used {Tar 44 parts B liquid Xylylene diamine 8 Example 3 In order to evaluate the workability of the coating film waterproofing agent according to the present invention, Example 1 Using the same polymer as used, solutions A and B were prepared according to the following formulation, and the changes in Brookfield viscosity over time and pot life of the two-part mixture were measured at the construction site.

Table 3 also shows data on the water resistance of coating films obtained by curing these assemblies at 20° C. for one week.

Here, formulations E and F are comparative examples in which a typical amine other than xylylene diamine is used as a curing agent for the polymer.

From these results, it is clear that the paint film waterproofing agent according to the present invention has a long pot life during application, and the water resistance of the paint film is very excellent.

Blending recipe Polymer Active zinc Chinese liquid FEF Carbon black Soft crater Norexylylene diamine Tetraethylene pentamine Liquid B N-Aminoethylpiperazine DEF 100 parts 100 parts 100 5 5 5 4 4 4 20 20 20 21 21 21 8 parts Part part 8 8 Terre 42 42 42 Example 4 Hardening agent B using liquid A with the same formulation as formulation A in Example 1
Table 4 shows the results of one adhesion test for coating film waterproofing agents obtained by changing only the liquid as shown in Table 4.

Here, the compounding recipe (3) shows a comparative example in which the amount of curing agent is small.

Claims (1)

[Claims] 1. For 100 parts by weight of a liquid chloroprene-based polymer having a xanthate group represented by the formula ROC-S- (wherein R is a carbon i S hydrogen group having 1 to 12 carbon atoms), At least 2 parts by weight of activated zinc white and/or basic zinc carbonate having an average particle size of about 100 millimicrons or less, 10 to 1 part of a softening agent.
50 parts by weight of the coating film and at least 5 parts by weight of xylylene diamine as a curing agent for the polymer.