DE2435656A1 - Insulating material prodn. - from expanded mica and hydraulic binder with absorptive additive based on sodium disilicate - Google Patents

Abstract

Prodn. of insulating matls. from expanded mca and a hydraulic binder according to the Parent Patent No. 2257551 is improved in that the granulometric compsn. of the expanded mica is: particles >1000 mu, 15.1-2.2%, 750-1000 mu 27.9-12.4%, 500-750 mu 32.9-33.4%, 300-500 mu 12.5-23.8%, 200-300 mu 6.9-15.6%, 100-200 mu 3.4-10.2%, and particles 100 mu 1.3-2.4%; an absorptive aditive based on sodium disilicate is included; the hydraulic binder consists of (a) a mixt. of sintered, finely comminuted components contg. stone slour and a surfactant (as normally used in plaster and mortar compsns.) and (b) a high-alumina cement based on lime and bauxite, produced by melting, cooling in the air, comminuting and grinding. This material can be used for sealing joints in walls, levelling and insulating floorings, plasters barring heat, sound and fire, stamping preparations for industrial furnaces, insulation for cooling installations, fire-preventing coating for steel constructions, mortar for buildings etc.

Description

Insulation mixtures (addendum to patent application P 22 57 551.5-45) The invention relates to insulation mixtures based on expanded Mica materials and hydraulic binders.

Mica materials are already bound as aggregates Shape has been used. Their special characteristics allow in practice that e.g. in the case of temperature differences, the stresses that occur are balanced out and the formation of cracks is thus reduced to a certain minimum. Even As a rule, good adhesion to the substrate can be achieved with such mixtures.

Mica materials are already available as such in bulk used for various types of insulation.

However, when looking at a cohesive end product such as in the case of plaster and linings, the loose fill comes - in spite of the good insulating properties of mica materials - of course, out of the question, but you have to add a binding agent.

Common binders in the construction industry include cement, lime, gypsum, Alumina fused cement, clay, etc.

However, it has been found that such mixtures, which for Common mica binder with a grain size of 0.1 to 15 mm as an aggregate has been added, not that which is constantly increasing in practical use Requirements for mechanical and thermal endurance strength and above all also suffice for alternating loads. The solution to these problems through deployment such mixtures, which are not only versatile, but also the highest Satisfying physical and application requirements is the object of the invention.

According to the invention this object is achieved in that the insulation mixture made of expanded mica with a particle size distribution according to the sieve analysis Grit > looo p: 15.1 to 2.2%> 750 p to 1ooo r: 27.9 to 12.4%> 500 p to 750 P: 32.9 to 33.4%> 300 P to 500 p: 12.5 to 23.8%> 200, u to 300 p: 6.9 to 15.6%> loo µ to 200 µ: 3.4 to 10.2% <100 µ: 1.3 to 2.4% a silicate additive based on sodium disilicate with good absorption capacity and from hydraulic binders, namely a) on the basis of one for production Mixture of sintered finely ground components suitable for plastering and masonry mortar containing stone dust and surface-active agents and b) conventional alumina cement on the basis of limestone and bauxite (produced by melting together, cooling in the air, crushing and grinding).

Preferred mixing ratios (each added to 1008) for the Insulation mixtures are as follows: Mica 10 - 30% by weight hydraulic binder a) 50 - 80% by weight hydraulic binder b) 4 - 20% by weight silicate additive o, 4 - 2.5 wt. T The following ranges are particularly suitable: Mica 19 - 25 wt.% Hydraulic binder a) 61-68% by weight hydraulic binder b) 6-16 Weight t of silicate additive 0.7-1.5% by weight The hydraulic binder a) is a commercially available product. The addition of the alumina cement accordingly the hydraulic binder b) is of particular importance in the invention. As a result of the composition and the method of manufacture, this shows alumina cement b) practically no lime precipitation during setting and hardening, so that Lime also does not appear as a solid phase in the hardened cement.

The hydraulic binder b) corresponds to the following average Standard analysis; Al2O3 40 ° SiO2 5% Na2O 0.05% CaO 38e TiO2 2% SO3 0.05% Fe2O3 lot MgO o, 6o% S 0.03% FeO 5% K20 o, o5% The suitable mixture of hydraulic binders a) and b) is responsible, among other things, for the advantageous application properties the insulation mixtures according to the invention or those produced therefrom and according to end products obtained after setting.

The silicate additive based on sodium disilicate is easily soluble Free-flowing, high-volume product that is usually obtained from water glass solution will. This product with the technical data Na2O 28.5 to 29% 5iO2 59 to 60% H20 12% + 1 is commercially available. In the insulation mixtures according to invention it is also used to regulate the bulk weight.

This silicate additive has an excellent absorption capacity for liquid components in the mixtures. Among other things, it maintains the flowability of the inventive powder mixtures.

The mica raw material obtained during extraction as granules has the following physicochemical data: Chemical mean analysis Spexifisches Weight: 2.6 SiO2 39.37 Sintering temperature: approx.1.2600C Ti Os 1.25 AI2OJ 12.03 Melting point: approx. 1.3150C FeO. 5.45 Fe2O3 5.45 Specific heat: 0.2 FeO 1.17 Fire resistance: up to 1.1000C Mn 0 0.30 Mgo 23.37 Ca 0 1.46 l (ationic exchange capacity of Na2O 0.80 90-100 milli-equivalents per 100 g K20 2.46 H2O + 105 ° C 5.18 H2O-105 ° C 6.02 Chemical Behavior: inert to Co2 0.60 organic solvents P205 0.15 Li20 0.03 ZrO2 Nil pH value: 7; however, since the material is low in Cr20s Nile bound minerolic V2O3 Nil contains impurities, the reaction is normally alkaline.

Ni O Nil Coo Nil BaO 0.03 Hörle: 1.5 according to the Mohs'schon scale. Cl 0.02 F Nile SOs 0.02 S 0.18 Total 99.91 If this granulate is a Undergoes expansion in the usual thermal way, the resulting Expanded product has a grain size in the range from 0.1 to 15 mm and density between 60 and 300 kg / m3. These are for Eloch performance and continuous performance demands values that differ too greatly. Therefore, the above-mentioned granules are fractionated sifted; the coarse fractions are separated out. Selected and ready to expand medium and fine fractions are used, provided that they are obtained after the expansion treatment the grain sizes result in the range according to the invention.

The specially selected expanded mica thus obtained is for the mixtures according to the invention are of particular importance.

The typical platelet structure is retained. The density then varies between 100 and 300 kg / m3. The product is light, inactive and incombustible. It has thermal conductivity under normal conditions of The practical application in the insulation mixtures according to the invention ensures that the cured masses ensure excellent resistance to long-term temperature and thermal shock loads at values of up to above 15000C.

Special proportions in the mixtures according to the invention can be varied within the specified ranges depending on the application.

The invention is explained in more detail below, for example.

Example The following five mixtures (recipes) were prepared and after setting, e.g. in the application at Chimney insulation, examined: Component I II III IV V hydraulic binder a) 400 kg 425 kg 450 kg 450 kg 450 kg hydraulic 40 kg 76 kg 68 kg 9o kg 112 kg binder b) Silicate additive 4 kg 8 ky 7 kg 9 kg 11 kg mica 145 kg 125 kg 160 kg 160 kg 160 kg water 475 kg 504 kg 531 kg 531 kg 531 kg The compressive strengths for these mixtures in the set form are between 8 kg / cm² and 21 kg / cm².

these mixes are new ready-to-use mortar mixes on the basis of the mixing ratios according to the invention with the particular grain size of the expanded mica, with water being added for processing. Of the The advantage is, among other things, that only a small amount of water is necessary and consequently a faster drying out can take place. This means a lot of time on construction saved because the work (e.g. applying mortar to surfaces or filling Wall slitting etc.) can be done in one passage.

With the specified special binder mixture, it is still possible to to maintain rapid green stability and completely eliminate corrosion.

The mixtures according to the invention can be used in certain constituent ratios (varying with the special purpose) prefabricated and delivered to the construction site to be delivered. Only there is the admixture of water, whereupon the setting takes place takes place. The advantages of these new mixtures are mainly based on the following Features: 1) Variable mixing ratios for a wide variety of uses.

2) Possible uses for high-performance insulation over 15000C.

3) Easy to use when mixing with the machine or by hand Water and subsequent processing.

4) High compressive strengths (8-21 kg / cm²).

5) Fast green strength.

6) Good bonding bridge for all types of plaster to be applied subsequently.

7) Shrinkage, cracking, loosening or swelling after setting omitted.

8) Good water retention capacity and therefore better surface adhesion.

9) No corrosive components in the mixture.

The insulation material according to the invention is great in its application versatile; Here are some other uses: 1) Wall slit thinning 2) Floor insulation 3) Incorrect floor leveling 4) Plaster to protect against heat, cold and noise and fire 5) ramming material in industrial furnace construction or the like.

6) backfill 7) cold store insulation 8) sheathing of steel structures, e.g. as fire protection 9) Ready-to-use mortar for building construction.

The specially selected grain size of the expanded mica greatly reduces the heat transmission at higher temperatures. The coefficient of thermal conductivity under normal conditions is The set material has a very low thermal conductivity and therefore very good thermal insulation properties, low specific heat, very good thermal shock resistance and a low density.

Those prepared using the mixtures according to the invention finished products are made of inorganic material and are therefore incombustible and thermally stable. They are dimensionally stable, pressure-resistant, sound-absorbing, light and physiologically harmless and also resistant to organic substances, to Weather influences and largely against acids and alkalis. Furthermore, they behave neither promoting nor causing corrosion.

Claims (1)

Claim Insulation mixture containing expanded mica and hydraulic Binder, as an addition to patent application P 22 57 551.5-45, characterized in that that they are made of expanded mica with a particle size distribution according to the sieve analysis Grain size> 1000 µ: 15.1 to 2.2%> 750 P to looo µ: 27.9 to 12.4%> 500 yes to 750 P: 32.9 to 33.4%> 3oo µ to 500 P: 12.5 to 23.3%> 200 P to 300 p: 6.9 to 15.6% 100 µ to 200 p; 3.4 to 10.2% <100 P: 1.3 to 2.4%, a silicate additive based on sodium disilicate with good absorption capacity and from hydraulic binders, namely a) on the basis of one for production of plastering and masonry mortar suitable mixture of sintered finely ground components containing stone dust and surface-active agents and b) conventional alumina cement on the basis of limestone and bauxite (produced by melting together, cooling in the air, crushing and grinding).