RU2766181C1 - Building mixture for manufacturing heat insulation products - Google Patents

Abstract

FIELD: building.

SUBSTANCE: invention relates to the field of building materials, namely, to production of building mixtures for manufacturing heat insulation products based on a gypsum binder and a plant-based filler – Sosnowsky's hogweed. The building mixture for manufacturing heat insulation products comprises, wt.%: high-strength G-10 grade gypsum binder 35 to 40, dried crushed Sosnowsky's hogweed with a density of 95 to 110 kg/m³, pre-treated with a solution of a Sika Sikagard - 700S hydrophobing agent by spraying, followed by drying to a constant weight, 20 to 25, water 38 to 40, wherein said hydrophobing agent is contained in an amount of 10 wt.% of water.

EFFECT: increase in the sorption and heat insulation properties of products made of the above mixture.

1 cl, 2 tbl

Description

The invention relates to the field of building materials, namely to the production of building mixtures for the manufacture of heat-insulating products based on gypsum binders and vegetable filler - Sosnovsky's hogweed.

Known raw material mixture for the manufacture of products based on gypsum binder [1], containing calcium sulfate hemihydrate, calcium-containing wastewater sludge of radio engineering, dried to constant weight, and water, additionally contains a modifying additive with a specific surface area of 500 m ² /g, obtained by joint grinding glauconite sand with a SiO ₂ content of 87% and superplasticizer C-3 in an amount of 1% by weight of sand, with the following ratio of components, wt.%: calcium sulfate hemihydrate 55-57, calcium-containing sewage sludge of radio engineering production 5-6, modifying additive 10 -15, water - the rest (RU No. 2368587 of 03/17/2008).

However, the known mixture is aimed at increasing the compressive strength and reducing water absorption and does not solve the problem of air purification due to low sorption and heat-insulating properties. The composition also includes a superplasticizer additive consisting of sodium polynaphthalene methylsulfonate, which belongs to substances of the 3rd hazard class.

Also known is a raw mix for the manufacture of gypsum concrete [2], including a binder of semi-aqueous gypsum, limestone flour and fluff pulp, and as a lightening agent, hollow polyurethane foam microspheres are used in the following ratio, wt.%: semi-aqueous gypsum - 15.2-53 .0; polyurethane foam crumb - 1.5-4.2; limestone flour - 17.0-37.0; fluff pulp - 1.6-4.2 (RU No. 2188176 of 07/04/2000).

The disadvantages of the known mixture are high density, low heat-shielding properties, as well as the multicomponent nature of the raw mixture.

Known composition of cement-bonded blocks [3], consisting of, wt.%:

wood chip filler 37-43 quartz sand 10-15 Portland cement 33-38 sodium silicate 0.7-2% water 2-19

(RU No. 2578077 dated 03/20/2016).

The disadvantage of this technical solution is the complexity of the technological process, which consists in the obligatory ensiling of raw softwood chips, the duration of hardening in pallets (at least 7 days, the complexity of the composition, including an organic filler containing up to 30% of large chips up to 5 cm long, and so the same tree bark up to 30%).

The closest to the proposed solution is a gypsum mixture [4], consisting of a binder based on semi-aqueous gypsum and hollow microspheres with the following content, wt.%: binder based on semi-aqueous gypsum 40-90, hollow microspheres 10-60, mixing water - until required density (RU No. 2476402 dated February 27, 2013).

The disadvantages of this technical solution include low values of sorption properties and high cost of raw materials (microspheres).

The technical objective of the invention is to create a mixture to obtain heat-insulating products with high sorption and heat-insulating performance.

The technical result is achieved through the use of available organic plant materials as a filler, which has a low density, thermal conductivity and high sorption capacity. To prepare the mixture for products, a gypsum binder was used, products from which are traditionally considered to regulate the microclimate in the room. Gypsum in the filler-binder system enhances the sorption and moisture exchange processes of the product with the environment.

Sorption characteristics are important parameters for materials and products used indoors, since these parameters play a significant role in maintaining comfortable conditions for humans, in particular, providing and maintaining clean air.

The modification of hogweed was carried out in order to give it water-repellent properties. The treatment was carried out with a water repellent Sika Sikagard - 700S. Crushed cow parsnip Sosnowski was evenly distributed over a plane 10 mm thick, sprayed with an aqueous solution of water repellent Sika Sikagard - 700S. Then, the treated hogweed was dried in an oven to constant weight. The resulting modified filler was used to prepare this composition. The mass of dried processed Sosnowski's hogweed differs from the mass of unprocessed hogweed by 29-32%.

For the composition, tap water at room temperature was used with the addition of a water repellent in a ratio of 1:10.

A high-strength gypsum binder grade G-10 was used.

Composite material containing dried crushed Sosnovsky's cow parsnip treated with a water repellent, gypsum binder, water, at the following ratios of components, wt.%:

cow parsnip modified 20-25 gypsum 35-40 water 38-40

The water repellent is contained in an amount of 10% of water.

Gypsum mix is made according to the following technology.

First, the dried hogweed was crushed in a rotary crusher to a maximum fraction of 2.5, sieved through a standard set of sieves to exclude dust particles. Get polyfractional composition. Then the crushed cow parsnip was subjected to hydrophobization by spraying with a solution of a hydrophobiser. The required amount of water was added to the dried hydrophobized hogweed, and then the gypsum binder was gradually introduced and mixed with a high-speed mixer until a homogeneous mass was obtained.

Experimental determinations of sorption and thermal insulation properties were carried out according to standard methods (GOST 24816-2014 and GOST 7076-99).

As can be seen from Table. 2, the proposed composition has low thermal conductivity and density, as well as improved sorption characteristics. The density of the product from this composition is 450-475 kg/m ³ , the coefficient of thermal conductivity is 0.11-0.12 W/(m⋅°C), sorption rates are 31-35% and 21-30% with benzene and acetone sorbents, respectively.

Table 1

Components
plaster
building mix The content of components, wt.% in the composition of the material Famous one 2 3 Sosnowsky's modified hogweed - 23 25 twenty Gypsum binder 40 - 90 39 35 40 Water Before TG 38 40 40

*TG - required sand density

The water repellent is contained in an amount of 10 wt.% of water

When implementing the proposed mixture and method for manufacturing heat-insulating products, the environmental situation improves, federal budget funds are saved for the fight and destruction of this weed, additional jobs are created in sparsely populated residential areas with the possibility of producing affordable budget building materials for low-rise housing construction.

Sources of information

1. RU No. 2368587 C1, publ. 03/17/2008.

2. RU No. 2188176 C2, publ. 08/27/2002.

3. RU No. 2578077 C1, publ. 03/20/2016.

4. RU No. 2476402 C2, publ. 02/27/2013.

Claims (3)

Building mixture for the manufacture of heat-insulating products, containing a gypsum binder, filler, water repellent and water, characterized in that high-strength gypsum binder grade G-10 is used, and as a filler it contains dried crushed Sosnovsky hogweed with a density of 95-110 kg / m ³ , previously treated with a solution of water repellent Sika Sikagard - 700S by spraying followed by drying to constant weight, in the following ratio, wt.%: Specified cow parsnip Sosnowski 20–25 High-strength gypsum binder grade G-10 35–40 Water 38–40, while the specified water repellent is contained in an amount of 10 wt.% of water.