SU1071615A1 - Heat insulation composition - Google Patents

Abstract

HEAT-INSULATING MASS, including kaolin fiber, refractory clay, prliacrylamide, a binder and fine filler, different from. By the fact that, in order to increase the mechanical strength and heat resistance, it contains as a binder an aqueous solution of aluminum-chromophosphate, and as a finely dispersed napol. nitel - talc, in the following ratio of components, wt.%: Kaolin fiber 23.8-56.5 Refractory clay 2.0-15.0 Iolyacrylamide 6.2-1.0 Aqueous solution of al i mochromophosphate 17.5-35, 0 Talc10.0-40.0 W

Description

SP

The invention relates to the field of refractory heat insulating materials intended for insulating thermal units, as well as for insulating profitable extensions when casting steel.

Thermal insulation products manufactured on the basis of kaolin fiber and polyvinyl acetate dispersion, which are currently produced by industry, as a binder, have good heat of heat and oxygen, but they have drawbacks. First, these products are used one-time, since the organic bond, polyvinyl acetate dispersion, is destroyed at 260 ° C, which leads to a loss of strength and destruction of the products themselves. Secondly, the cost of such products is very high (kaolin fiber and polyvinyl acetate binder are expensive materials). It is necessary to obtain heat-insulating reusable products for service at high temperatures and significantly reduce the cost of such products by replacing the binder with more fire-resistant and cheaper, as well as partial replacement of expensive kaolin fiber with cheaper materials that at the same time have good refractory and thermal insulation properties.

The composition of heat insulating materials is known, including aluminous silicate fibers and inorganic finely dispersed binder JV.

The disadvantage of this mass is the complexity and complexity of the technology. In addition, heat-insulating products of this mass are characterized by a high apparent density, increased heat-conducting properties, and relatively low heat-resistant properties.

Also known is the mass of C2 for heat insulating materials, containing the following components, wt.%:

FireclayBase.

Refractory clay 8-9, Kaolin fiber 10-12 surfactant 0.5-1.0 The disadvantage of this mass is increased apparent density, insufficiently high mechanical strength in the unfired form, relatively low heat resistance, and at & khz increased thermal conductivity. In addition, the kaolin fiber introduced into the dry mass is distributed unevenly over the volume of the mass, which causes the fiber properties to be unequal, and has low adhesive properties, as if the initial components are separated, which leads to a decrease in the mechanical strength of the products in the unbaked form. .

Closest to the invention in its technical essence and the achieved result is the heat insulating mass C31, including wt.% Kaolin fiber 76-90 Refractory clay 4-9 Polyacrylamide 1-3

Organic Binder 4-9 Fine refractory filler 1-3 The disadvantage of this mass is that the organic binder contained in it (: field of INN l adatat, vynyl acetate copolymer with dibutyl maleinate) when heated to 260 ° C is destroyed, and articles of this mass lose their ability to elastically deform. A further increase in temperature leads to the fading of organic matter and to. further shrinkage, loss of mechanical strength, increased porosity and gas permeability of the mass. Products of this mass can not be used repeatedly, as well as directly in contact with the fire, since very low compressive strength (0.76-2.0 kg / cm is a potential cause of an emergency situation).

The purpose of the invention is to increase the mechanical strength and heat resistance.

The goal is achieved by the fact that the heat insulating mass, including kaolin fiber, refractory clay, polyacrylamide, binder and fine-dispersible filler, contains an aqueous solution of aluminum-chromophosphate as a binder, and talc as a fine-dispersed filler, in the following ratio of components, wt.% :

Kaolin fiber 23,8-56,5 Refractory clay 2,0-15,0 Polyacrylamide 0,2-1,0 Water. A solution of aluminum, mochromophosphate l7,5-35,0 Talc 10.0-40.0 Preparation of thermal insulation This mass is carried out as follows.

A clayey slip is successively mixed with poly acryl amber up to 5 “1, and then with fiber pre-ground to 5–10 mm. Aolin fiber for 5–7 min. After coagulation and sedimentation of clay particles on the fibers, excess water is removed. The clay film created in this way contributes to the adhesive bonding of the fibers, both among themselves and with other solid particles of the mass. An aqueous solution of an aluminum-chromophosphate binder (LHOSC is mixed with talc and then with previously prepared fiber covered with a clay film. The resulting mass is molded into specimens, kept in air for 1 day, and then subjected to heat treatment in a drying cabinet at 250-350 ° C. Samples are held until moisture is completely removed.

When aluminum chromophosphates, talc and clay are introduced into the mass of the aqueous solution, the lubricant molecules interact with the D-oxide (1A fillers, as well as the polymerization and polycondensation of the phosphate molecules, which contributes to an increase in the mechanical strength of the unbaked products.

When the mass is heated during the drying process, the concentration of aluminum chromophosphates increases as a result of the removal of physical and partially chemically bound water. This contributes to the formation of new chemical compounds in conjunction with it and to the strengthening of adhesive surfaces. As a result, the strength of the mass increases.

Example 1. A slip from 0.2% polyacrylamide is prepared from 2% of clay and mixed with 23.8% pre-ground kaolin fiber for 5-7 minutes. After the coating on the fibers of the clay film, excess water is removed. 35% aqueous solution of aluminochromophosphates are mixed with 40% talka, and then with previously prepared fiber for 5-7 minutes. From the mass thus obtained, samples are formed with a size of 110x110x20 mm, are first kept in air for 1 day, and then heat treated. work in an oven at 350 ° C until moisture is completely removed

In examples 2 and 3, samples were prepared according to the method of example 1, compositions. masses according to examples 2 and 3, respectively, wt.%: Kaolin

23.8 56.5 76-90 fiber Clay refractory8 4-9 by 2

15 Polyacryl0

1-3

0.5 25 26

one

0.2

amide

. : 40.

10 Talc AHFS 17.5 35

Organic binding. - - - 4-9 5 Fine refractory filler. - - - 1-3. After drying, the samples are subjected to 0. test See, the results of which are shown in the table. ; .

With a decrease in the content of kaolin fiber, the mass is characterized by high values of apparent density and thermal conductivity, while. increasing the content of fiber and clay - a significant decrease in the mechanical strength pt by an increase in thermal conductivity, which reduces the efficiency

masses as heat insulations;

thirty

Thus, this heat insulating mass based on kaolin fiber is characterized by high performance properties that allow multiple use of products, use them in contact with high temperature and significantly reduce their cost.

Claims (1)

THERMAL INSULATION MASS, including · kaolin fiber, refractory clay, polyacrylamide, a binder and a finely dispersed filler, characterized in that, in order to increase mechanical strength and heat resistance, it contains an aqueous solution of alumina phosphate as a binder, and talc as a finely divided filler ratio of components, wt.%: Kaolin fiber Refractory clay Polyacrylamide Aqueous solution of alumochromophosphate Talc