RU2402663C2 - Multilayer structural material and method of its production - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: method for production of multilayer structural material includes mould filling, subsequent supply of layer materials, moulding, soaking, withdrawal from mould. At the same time serial filling of layer materials is carried out through placement of basalt cloth layers impregnated with epoxide resin onto mould bottom, placement of foam polyurethane layer onto layers of basalt-plastic with further laying of basalt cloth layers impregnated with epoxide resin onto foam polyurethane layer, with intermediate arrangement of carbon threads in between. Ends of carbon threads are taken outside. Moulding and soaking of all layers is carried out simultaneously in process of heating up to temperature of 60°C and pressure of 0.5-1.0 MPa until resin hardens. At the same time ratio of foam polyurethane layer thickness to basalt-plastic layer thickness makes 20-80:0.5-1.5.

EFFECT: improved mechanical properties and reduced process cycle.

2 cl, 2 dwg, 1 tbl

Description

The invention can be used in wall and roof sandwich panels, for sheathing aircraft and deep-sea vehicles, river and sea vessels as structural heat and sound insulating material.

A multilayer building element is known consisting of a central layer (mineral wool strips) and surface layers located on two opposite main surfaces of the central layer, obtained by gluing surface layers to opposite main surfaces of the central layer. The surface of the middle layer is made profiled with grooves, and the surface layers repeat the contour of the surface of the middle layer [1].

The profiling of cladding sheets and mineral wool boards in compliance with the accuracy of coincidence of the protrusion with the hollow of the sheet and plate, applying glue to the outer layers and gluing complicate the process.

Known multilayer structural material used in sandwich panels, including two surface layers of metal and a central part drawn from pieces of mineral wool strip, between which longitudinal strips of filling foam (polyurethane, etc.) are located, where the central layer is made of mineral wool stripes alternates with polystyrene, obtained by pouring mineral wool pieces into a foamed mass of polyurethane foam and metal sheets are glued to the resulting structure [2].

The disadvantages of this design is the difficulty of manufacturing, the use of an expensive metal sheet as the outer layer.

Known multilayer structural material used in the manufacture of wall panels, characterized in that it consists of an average polyurethane foam insulation layer, the surface of which is profiled with grooves, and outer layers made of galvanized steel with a thickness of 0.5-0.7 mm with a protective and decorative paintwork or without it.

A multilayer structural material was obtained by pouring a foamed polyurethane foam mass into a mold, profiling the outer surface of the polyurethane foam layer with grooves and gluing the polyurethane foam preform with a pre-shaped sheet of rolled metal [3].

The disadvantages of this design are poor compatibility of the materials of the layers, low adhesive and bending strength, rigidity, multi-stage process.

A well-known multilayer structural material used in the manufacture of wall panels, taken as a prototype, characterized in that it consists of two side planed bars and a polyurethane foam plate located between them with a density of 25-70 kg / m ³ , while the front and back sides of the plate polyurethane foams are covered with a layer of protective material made of paper, foil or plastic film, fixed due to the adhesive properties of polyurethane foam. The material was obtained by pouring foam into the mold, on the bottom of which protective material is laid, wooden blocks on the sides. A protective material is laid on top of the foam mass, after which the resulting structure is kept under pressure [4].

The structural strength is ensured by the properties of polyurethane foam, surface protective layers do not improve the mechanical characteristics of the material.

A known method of manufacturing a multilayer building blocks containing a facing, heat-insulating and structural layers, including the installation of technological partitions into the form, filling the form with a sequential supply of solutions of the facing, heat-insulating and structural layers, molding, holding and removing from the mold. At the bottom of the mold, plates of elastic elastic material are placed, the sizes and configuration of which correspond to the sizes and configuration of the blocks being manufactured, and plates with a film of elastic flexible material located along their lower ends and side surfaces, which are installed after filling the mold, are used as technological partitions. lower ends in the gap between the said plates of elastic material, exposure is carried out before the setting of the solutions, then the plates are removed of technological partitions, leaving the aforementioned film fixed between the ends of the plates of elastic material until the solutions solidify completely.

The disadvantages of this method is the multi-stage process.

The objective of the invention is to improve the mechanical characteristics, reducing the process.

In contrast to the prototype, the created multilayer structural material, the inner layer of which consists of polyurethane foam, and the surface layers are made of basalt plastic, consisting of several layers of basalt fabric, impregnated with resin or basalt plastic, consisting of several layers of basalt fabric, impregnated with resin and laid between them carbon filaments, a combination of well-compatible components is used - polyurethane foam and basalt plastic and placement of the carbon fiber in basalt plastic, providing that feels the possibility of electric heating.

To achieve the named technical result in a method for producing a multilayer structural material, including filling a mold with a sequential supply of layer materials, molding, holding, extracting from a mold, sequential feeding of layer materials, perform the following sequence: layers of basalt fabric impregnated with epoxy resin are placed on the bottom of the mold, or layers of basalt fabric impregnated with epoxy resin, and carbon filaments are placed between them, the ends of which are brought out. Then a layer of polyurethane foam, preformed in an identical form, is placed, layers of basalt fabric impregnated with epoxy resin are laid on it, or layers of basalt fabric impregnated with epoxy resin, and carbon filaments are placed between them, the ends of which are brought out. The formation and aging of all layers is carried out simultaneously when heated to 60 ° C and a pressure of 0.5-1.0 MPa until the resin is cured.

To achieve this technical result in a multilayer structural material containing a central polyurethane foam layer and surface layers, the surface layers are made of basalt plastic or a layer of basalt plastic with carbon fibers laid inside it, the ends of which are pulled out, with the ratio of the thickness of the polyurethane foam layer to the thickness of the basalt plastic layer 20-80 : 0.5-1.5.

To create a multilayer structural material are used:

polyurethane foam brand PPU T-205PN TU2254-011-43862634-07;

basalt fabric BT-12 TU 5952-031-00204949-95;

epoxy resin brand ED 20 GOST 10587-76;

carbon thread - Balakovo fibers.

Figure 1 presents a diagram of the formation of a multilayer structural material without carbon filaments inside basalt plastic.

Figure 2 presents a diagram of the formation of a multilayer structural material containing carbon filaments inside basalt plastic.

Table 1 presents the physico-mechanical characteristics of the prototype and the inventive multilayer structural material, depending on the ratio of the thickness of the inner layer to the outer.

Example 1. The multilayer structural material (Fig. 1) consists of a lower layer of basalt plastic 1 in the form of resin-impregnated layers of basalt fabric, a middle layer of polyurethane foam 2, an upper layer of basalt plastic 3 in the form of resin-impregnated layers of basalt fabric. The number of layers of basalt fabric in layer 1 is equal to two and in layer 3 is equal to two.

The production method is as follows. At the bottom of the mold we lay basaltoplastik 1 - layers of basalt fabric impregnated with resin, onto which we lay out a layer of identical polyurethane foam 2 previously obtained by molding, and we lay basaltoplast 3 - resin-impregnated layers of basalt fabric on top. The resulting structure is crimped by the outer part of the press tooling, which can be smooth or with protrusions. In order to reduce the curing time of the resin, we increase the temperature of the outer layer of the multilayer structural material to t = 60 ° C due to an external heat source and hold until the resin cures. The thicknesses of the layers are (20: 0.5) mm.

Example 2. The same as in example 1 with a ratio of layer thicknesses (50: 1,0) mm.

Example 3. The same as in example 1 with a ratio of layer thicknesses (80: 1,5) mm.

Example 4. The multilayer structural material (Fig. 2) consists of a layer of basalt fabric 1 impregnated with resin, on which a carbon thread 2 with outgoing ends 3 is laid, a layer of basalt fabric 4 impregnated with resin, a layer of polyurethane foam 5, a layer of basalt fabric 6, impregnated with resin, on which a carbon thread 7 with outgoing ends 8 is laid, a layer of basalt fabric 9 impregnated with resin.

We obtain a multilayer structural material by sequential filling of the mold components: on the bottom of the press tooling we lay a basalt fabric 1 impregnated with resin, onto which we lay a carbon thread 2 with the ends 3 facing out, and cover with a basalt fabric 4 impregnated with resin. Next, a layer of polyurethane foam 5, preformed in an identical form, is placed on which a basalt fabric 6 impregnated with resin is laid, a carbon thread 7 is laid on it with ends 8 facing out and covered with a basalt fabric 9 impregnated with resin. The resulting structure is crimped by the outer part of the press tooling, which can be smooth or with protrusions. In order to reduce the curing time of the resin, we increase the temperature to t = 60 ° C, for which we pass an electric current through carbon filaments, the strength and voltage of which is determined by the size and configuration of the element. The curing process of resin in basalt plastic is accelerated several times. Subsequently, carbon fiber heating elements can be used as heat sources for heating the interior. The thicknesses of the layers are (20: 0.5) mm.

Example 5. The same as in example 4 with a ratio of layer thicknesses (50: 1,0) mm.

Example 6. The same as in example 4 with a ratio of layer thicknesses (80: 1,5) mm.

The data determining the physico-mechanical characteristics of the claimed material in comparison with the prototype are shown in table 1.

The advantage of the developed technology is.

The high strength of the adhesive bond between the layers of basalt plastic and polyurethane foam, which is ensured by the penetration of epoxy resin into the surface of the polyurethane foam layer and filling it with voids, creates a strong adhesive layer. The presence of basalt plastic as the outer layers significantly increases the strength characteristics of the entire structure, giving it the strength properties of both materials. The low coefficient of thermal conductivity of the structure is ensured by a combination of materials. The presence of electrically conductive carbon filaments in the basaltoplastics layer, through which electric current is passed, makes it possible to regulate the heating in the basaltoplastics layer, which helps speed up the resin curing process several times. Increases the efficiency of thermal insulation. Subsequently, carbon fiber heating elements can be used as heat sources for heating the interior.

In addition, by profiling the lower and upper surface of the element with press tooling, it is possible to obtain a multilayer structural element with stiffeners, while reducing the profiling operation as a separate one, which allows you to create a waste-free technology, further increases the strength of the structure.

Information Sources Used

1. Pat. 2270902, RF IPC E04C 2/26, 2/292. Sandwich panel / Khabelashvili Sh.G., Kisielius M.P., Bobryashov V.V. // Bull. - 2006. No. 6.

2. Pat. on PM 65920, RF IPC E04C 2/292. Sandwich panel / Hafizov M.R. // Bull. - 2007. No. 24.

3. TU 5768-116-02495282-01.

4. Utility model 65919, Russia IPC E04C 2/10. Wall polyurethane foam panel / Vasilets S.V. // Bull. - 2007, No. 24.

Claims (2)

1. A method of obtaining a multilayer structural material, comprising filling a mold with a sequential supply of layer materials, molding, holding, extracting from a mold, characterized in that the sequential supply of layer materials is performed by placing basalt fabric layers impregnated with epoxy on the bottom of the mold, placing a polyurethane foam layer on layers basalt plastic followed by laying on a foam-polyurethane interlayer of basalt fabric layers impregnated with epoxy resin with an intermediate I am waiting for them to carbon filaments, the ends of which lead out, molding and aging of all layers are carried out simultaneously when heated to a temperature of 60 ° C and a pressure of 0.5-1.0 MPa until the resin is cured at a ratio of the thickness of the polyurethane foam layer to the thickness of the basalt plastic layer 20-80: 0.5-1.5. 2. A multilayer structural material obtained according to claim 1, comprising a central polyurethane foam layer and surface layers, characterized in that the surface layers are made of basalt plastic or a basalt plastic layer with carbon fibers laid inside it, the ends of which are pulled out, with the ratio of the thickness of the polyurethane foam layer to the thickness of the layer of basalt plastic 20-80: 0.5-1.5.

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