Use of non-ionic cellulose ethers in grouting or coating materials

DESCRIPTION

GIVES

PATENT OF INVENTION

No. 90 358

APPLICANT: HENKEL KOMMANDITGESELLSCHAFT AUF AKTIEN.ale mother, established at 4000 Dusseldorf, Henkelstras se 67, Federal Republic of Germany.

EPIGRAPH: PROCESS FOR THE PREPARATION OF

COATING OR SEALING TOGETHER ON THE BASIS OF AQUATIC DISPOSALS OF POLYRACYLES OR ACRYLATE COPOLYMERS CONTAINING NON-IONIC CELLULOSE ETHER AS ADDITIVE

INVENTORS: Helmut Loth, Klaus Helpenstein, Tore Podola, and Bernhard Knop.

Claim of right of priority under Article 4 of the Paris Convention of 20 March 1883.

Federal Republic of Germany, 26 April 1988, under P 38 14 078.0.

INPI MOO 113 RF 16732

Ρ.Ι.Νθ

358

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DESCRIPTION OF THE INVENTION for

PROCESS FOR THE PREPARATION OF COATING OR SEALING PASTA JOINT BASED ON WATER DISPERSIONS OF ACRYLATES POLYACRYLATES CONTAINING CELLULOSE ETERES

NON IONICS AS ADDITIVE

HENKEL KOMMANDITGESELLSCHAFT AUF ΑΚΤΙΞΝ, German, Industrial, established at 4000 Dlisseldorf, Henkelstrasse 67,

Federal Republic of Germany.

SUMMARY i

The invention relates to the process for the preparation of joint coating or sealing compounds which contain aqueous dispersions of polyacrylates, plasticizers hem as usual additives such as pigments and the like and have excellent properties, especially from the point of view of ability. of paint and smoothing capacity, characterized in that at least one nonionic cellulose ether chosen from the hydroxyethylcellulose group is added, hydroxyethyl methylcellulose, hydroxypropyl methylcellulose and hydroxypropylcellulose, having a Brookfield viscosity as determined by a 2% aqueous solution at 20 ° C of at least 3000 mPa.se, especially a minimum of 5000 mPa.s.

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The invention relates to the application of cellulose ethers selected from the group consisting of hydroxyethylcellulose, hydroxyethylmethylcellulose, hydroxypropylmethylcellulose and hydroxypropylcellulose with viscosities according to Brookfielde in aqueous solution at 2 to 20 ° C of at least 3000 mPa.s, especially at least 5000 mPas, as additives for joint sealing and coating coatings based on aqueous dispersions of polyacrylates and acrylate copolymers to improve the coating strength and smoothing of the unhardened surfaces of these greases.

It is known as referred to in Ullmann, Enzyklopâdie der technischen Chemie 4^g. edition, pages 208-209, which derivatives of nonionic cellulose ethers, such as hydroxyethyl cellulose (ΗΞ0), hydroxyethyl methylcellulose (HEMC) and hydroxypropyl methylcellulose (HPMC), are applied to plastic coating mortars to improve water retention capacity, opening time, wet grip as well as thickening and setting capacity. In addition, German Patent DE-C 36 19 142 mentions the use of water-soluble cellulose derivatives as auxiliary agents for the mechanical smoothing of unhardened surfaces of pasty materials, in particular joint sealant, e.g. based on polyacrylates.

Commonly known coating and joint sealant formulations are generally smoothed after application with smoothing water or water / Holmer mixtures, for example according to DE-C 36 19 142. The use of agents The smoothing technique enables the formation of both technical and optically perfect connections between constructing elements as well as the equalization of faults on the surfaces of said masses. Enrichment of wetting agents contained in the smoothing agents reduces the slip resistance on

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and the straightening phase in it is possible. Upon enrichment in wetting agents, the formulation components may, under certain conditions, be emulsified on the surface of the pasta; Since in this way the concentration of the mass on the surface is altered, the technical properties of the sealing agents may be influenced. The involvement in the dough components can also act equally disadvantageously on the surface.

The invention relates to joint coating and sealing masses which, with excellent characteristics such as modulus of elasticity, elongation at break and shrinkability, exhibit improved overall overall smoothing ability and at the same time considerably improved migration resistance. , of the components of the formulation on the surface of the masses as opposed to conventional formulations. This is achieved by employing nonionic cellulose ethers chosen from the group consisting of hydroxyethyl cellulose, hydroxyethyl, hydroxyethyl methylcellulose, hydroxypropyl methylcellulose and hydroxypropylcellulose, with viscosities according to Brookfield in 2% aqueous solution, measured at 20 ° C, equal to at least 3000 mPa.s, in particular at least 5000 mPa.s, with additives to the aqueous dispersion-based coating and sealing compounds of acrylate or polyacrylate copolymers to improve the covering and smoothing ability of the non-hardened surfaces of said masses.

An essential and unexpected advantage of the coating and joint sealing masses according to the present invention is furthermore apparent from the so-called wash behavior, ie the applied and not yet dried mass remains adhered for a longer period of time. weather even under the effect of water, for example rainwater.

The invention further relates to coating or

<img file="PT90358B_D0004.tif" />

(b) nonionic cellulose ethers selected from the group consisting of hydroxyethylcellulose, hydroxyethylmethylcellulose, hydroxypropylmethylcellulose and hydroxypropylcellulose, with viscosities according to Brookfield in 2% aqueous solution at 20 ° C, at least 3000 mPa.s, in particular a minimum than 5000 mPa.s as well as

(c) usual additives such as pigments, wetting agents, plasticizers (diluents), antifoaming agents, dispersing aids as well as preservatives and aging protection agents | t o.

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According to a preferred embodiment of paragraph 1

Nonionic cellulose ethers selected from the group consisting of hydroxyethylcellulose, hydroxyethylmethylcellulose, hydroxypropylmethylcellulose and hydroxypropylcellulose having viscosities measured according to Brookfield in 2% aqueous solution at 20 ° C of at least 3000 mPa.s at least 5000 mPa.s are contained in an amount of 0.4 to 6.0, preferably 0.6 to 5.0% by weight, relative to the solids content of the dispersion.

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The aqueous dispersions contained in the coating and joint sealing masses according to the invention, containing beakers: acrylate or polyacrylate polymers, preferably have solids contents from 40 to 70, in particular from 45 to 65% by weight. Its pH value should be at least 7, in particular 8 to 9,

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In addition, the coating and rim seal masses of the invention may contain loads in an amount from 0 to -50, in particular from 2 to 50% by weight relative to the total mass of the joint and seal masses. Greases of this type have high transparency when they do not contain or contain very small amounts of fillers.

According to another advantageous embodiment of the invention, the joint coating and sealing masses contain, as plasticizers, chlorinated hydrocarbons, in particular chlorinated paraffins and, as wetting agents, nonionic surfactants. Commercially available chlorinated paraffins having a chain length of about 10 to 18 carbon atoms and a chlorine content of about 40 to 70% by weight are preferred.

Aqueous dispersions of acrylate and polyacrylate copolymers contained in the coating and joint sealing masses, as well as pigments, plasticizers, crosslinkers, antifoam agents, dispersing aids, as well as preservatives and anti-aging agents, as appropriate. Existing products are already marketed, which are known to those skilled in the art in the field of coating and joint sealing for construction purposes.

Nonionic cellulose ethers of the above specification to be employed in accordance with the invention are also commercially available pipelines.

In the following, the invention is further explained by reference to preferred embodiments.

The masses described in the examples, as well as other masses

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for comparison, were subjected to a slide test.

Pod, wherein an artificial rain producing apparatus according to Figure 1 is employed; the same apparatus is shown in Figure 2 in side view,

The artificial rain gear consisted of a box made of clear plastic with the following dimensions: 70 cm high, 60 cm deep and 60 cm deep. It comprised a housing 1, a shower nozzle 2, a test cuvette 3, a pump 4, a drain 5 and a sealing valve 6 for the flow. The test cuvette consisted of a 7 x 7 cm container and had a depth of 2.5 cm. As for the shower nozzle, it was a standard hand shower, as used for personal hygiene, and was adjusted in such a way that it produced regular artificial rain on the cuvette. The distance between cuvette 3 and shower nozzle 2 was 30 cm.

The apparatus was fed with demineralized water, which produced over-pressure of about 0.4 bars through the pump. The water supply was 300 l / h. Water spraying lasted 5 minutes, always 1 minute after application and smoothing of the surface of the test mass. Wash loss (in / by weight) was expressed by weight difference before and after exposure to water.

The masses described in the examples were further tested for their smoothing ability. This test was carried out by 7 persons working independently of each other, so that after applying a 30 cm long strip of dough on a dark, flat and smooth substrate, the dough was smoothed with a spatula and fingers. The straightening capacity was evaluated according to a scale of i

rating from 1 (= very good) to 6 (= insufficient).

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Example 1 In a planetary mixer the following ingredients were intensely mixed for about 45 minutes:

1750 g of an aqueous dispersion of butyl polyacrylate (about 62% solids) with a pH value of

8.8 to 8.5, a TO glass transition temperature of -50 ° C, a viscosity of about 250 mPa.a at 23 ° C and an average particle size of 0.4 µm,

250 g chloroparaffin (Gj.p.^-1-'24&gt; 49 / chlorine)

2800 g barium sulphate (commercial product: Schwerspat EWO),

100 g titanium dioxide (commercial product KRONOS RR 56), g sodium carbonate (technically pure commercial product), g ethylene oxide adduct (about 9,5 units of ethylene oxide) with nonylphenol, g of a halogenated preservative usual in commercial

10 g of hydroxyethylcellulose having a viscosity of about 40 ° C mPa.s in a 1% aqueous solution at 20 ° C and a hydroxyethyl content of 55% by weight; Trade name: Natrosol 250 HHR.

This mixture was packaged in 310 ml plastic containers and stored for a minimum of one year at temperatures up to 35 ° C.

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Workability according to BIX Standard 52456 (4mm bore; 2 bar pressure, 200 ml test volume): 2260 g / min.

straightening ability: good,

Wash loss: 1 / - loss.

After an overall addition of 50 g of the same hydroxyethylcellulose the following results were found:

Workability according to DIN 52 456: 1300 g / min

Straightening ability: very good

Wash Loss: 0.3 / Loss.

Example 2 ¹

In a planetary mixer the ingredients indicated in Example 1 were intensively mixed for about 45 minutes, but instead of 4000 mPa.s hydroxyethylcellulose were used:

g of hydroxypropylcellulose having a viscosity of about 5000 mPa.s, in a 2% aqueous solution at 20 ° C and with a 70% hydroxypropyl group content; Description Klucel Lí.

This mixture was placed in 310 ml plastic containers and was stored at least at temperatures up to 35 ° C.

<img file="PT90358B_D0009.tif" />

Workability according to DIN 52 456, measured as in Example 1: 2100 g / min

Good straightening ability

Wash Loss:

/ of loss.

Example 3

In a planetary mixer the ingredients indicated in Example 1 were intensively mixed for about 45 minutes, but instead employed 4000 mPa.s hydroxyethylcellulose:

g of a hydroxypropyl methylcellulose having a viscosity of about 20,000 mPa.s in an aqueous solution at 20 ° C and a hydroxypropyl group content of 3.2% by weight; Trade name: Culmin MHPC 20 000 PR.

This mixture was packaged in 310 ml plastic containers and was stored for at least 1 year at temperatures up to 35 ° C.

Workability according to DIN 52 456 measured as in Example 1: 2870 g / min

Straightening ability: good

Loss on washing: 3.5 / loss.

Example 4

In a planetary mixer the following components were intensively mixed for about 45 minutes:

<img file="PT90358B_D0010.tif" />

4700 g of aqueous dispersion of a butyl polyacrylate and reduced amounts of copolymerized acrylonitrile (60 ¢ solids content), pH value approximately 5-6 g of ethylene oxide adduct (about 9.5 units of ethylene) with nonylphenol, g of a commercially available antifoam mixture -KV / - silicone, g of commercially available phenolic preservative (Parmetol, SchUlke-Mayr, Hamburg),

102 g of dispersed silica (commercial product HDK V 15,

Wacker-Chemie), g of 25 ° C ammonia solution, cyioroparaffin solution (ΟΟ θ - C ^, 49% chlorine), of a hydroxyethylcellulose having a viscosity of about 4000 mPa.s in a 1% aqueous solution ¢ and a hydroxyethyl content of 55% by weight; Trade name: Hatrosol 250 HHR.

This mixture was packaged in 310 ml plastic containers and was stored at temperatures up to 35 ° C for at least one year.

<td> 36</td><td>cr O</td><td>in</td>

<td> 52</td><td>g</td><td>in</td>

<td> 18</td><td>CT O</td><td>in</td>

straightening capacity:

loss ror wash:

Unworkability according to DIN 52 456, measured as in Example 1: 3700 g / min good

4.5 / loss.

Example 5

In a planetary mixer the following ingredients were thoroughly mixed for about 45 minutes:

2795 g of a commercially available aqueous dispersion of a styrene and acrylic acid ester copolymer (about 50% solids) with a pH of about 8, a viscosity of 1200 mPa.s at 23 ° C and an average particle size of about 0.1 µm (anionic dispersion type);

180 chloroparaffin g (chain length - (ΟΟ θ - Cj ^), 40% chlorine);

1600 g barium sulphate (Schwerspat Cll, Sachtleben);

150 g of titanium dioxide (KRONOS RN 56);

g of polyacrylic acid sodium salt (Dispex No. 40);

100 g formalin (30% formaldehyde solution); ;

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120 bis (methylcyclohexanyl) phthalate; ;

g of hydroxyethylcellulose having a viscosity of about 400 mPa and an aqueous solution at 20 ° C and a hydroxyethyl content of 55% by weight; Trade name: Natrosol 250 HHR.

This mixture was packaged in 310 ml plastic containers and was stored at temperatures up to 35 ° C for at least one year.

<img file="PT90358B_D0011.tif" />

Workability according to Example 1:

Straightening Capacity:

Wash Loss:

DIN 52 456, measuring 1500 g / min, very good,

0.5 0 loss.

Comparative_Assays:

a) Example 1 was repeated without using hydroxyethyl cellulose:

Wash loss 23 /.

b) Example 1 was repeated in which, instead of hydroxyethyl cellulose, carboxymethylcellulose (DS 0.8, viscosity 400 mPa.s in 2%, aqueous solution at 20 ° C wash loss was used).

c) Example 4 was repeated without using hydroxyethyl cellulose:

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ι / loss by washing. j