PROCEDURE FOR THE PRODUCTION OF A STRUCTURAL PANEL
MODULAR BASED ON TERMOFIXED RESINS AND PRODUCT OBTAINED
TECHNICAL FIELD OF THE INVENTION The invention relates to the field of the construction industry, particularly related to the manufacture of panels of structural and modular type known in the medium as "sandwich type", by virtue of being formed by a top sheet and another lower one, generally of laminated materials, with different finishes, while in the intermediate part (core), between said laminates there is a generally foamed material that is considered to be an insulating filler, composed of polymeric materials. BACKGROUND OF THE INVENTION In the international market, it is common the use of various plastics in the area of construction, conditioning, insulation and finishing of buildings and buildings. In Mexico, the use of traditional materials such as brick, iron, steel and steel laminates still predominates. There are countless composite materials with which the panels are formed, for example: the panel known as "Multypanel" composed of polyurethane compressed with a layer of metal foil. Another type of panel is the one known as type V, made from resins and a framework made of wire, mortar, cement and sand. There are also derivations of each panel as described, of different brands and thicknesses, whether panels formed by agglomerates and finished with formica layer and / or plastic laminates, or panels with metal frame, finished in porcelain steel, for dividing walls and screens for bathrooms and urinals, among others. Worldwide, the word "panel" is used to refer to a type of sheet or sheet of material, be it metal, plastic or the so-called "composite", with an intermediate filling element of material different from that of the laminated material. For the purposes of clearly describing the present invention, when using the term "structural panel" it should be understood as a type of panei constituted by two sheets, one lower and one upper, made with different thermosetting resins and a base filling material. also of foamed thermoset resin, preferably of polyurethane. Some other types of panel currently in the Mexican market, include those manufactured by companies such as Industrias Monterrey, Galvak, Panel Rey, Convitec, Panel W, among others. At the international level, there are panel versions considered as leaders in these products: Metecno, Italy; Kingspan, Great Britain; Goethe, Germany; Alucobond. The current state of the art is determined in a large number of very precise patent documents, among which they refer to some representative versions of panels. For example, US Pat. No. 095400549, PCT 19891122, refers to laminates, panels and means for joining them, in this case the sheets or sheets involved are metallic, covered with another material and / or filled with other types of materials. In this way, it is very impractical to have metal sheets in their assembly and manufacturing together with the cost of their manufacture. The document FR E 8402514, EURO9880617 refers to a type of lightened "sandwich" panel, intended for the realization of multilayer structures that resist collisions and thermal aggressions. This case also refers to a sandwich based on metal plates, having as center a metal sheet, a honeycomb panel with internal reinforcements of aramid fiberglass. As you can see, it is a complex panei with significant sophistications in the manufacturing process. For its part, the Italian patent IT E 98103577, EUR08103577 refers to a panel of "composite" in particular for partitions, external coatings for walls, doors and windows or similar. It is a panel of quadrangular tiles that is used in partition walls, coated Japanese patent JP E 98101575, EURO9980129 comprises the manufacture of a heat insulating panel, vacuum and process to manufacture it. It is an insulating panel of metal faces with foam in the center based on polyurethane. Again the complex aspect is the type of material used in the faces that is metallic, which makes its coupling and adhesion to the other filling material complex. The document BE E 6830359, EURO9960621 consists of a structure of
"composite" prefabricated for the formation of a sloping roof. Here we have a panel with certain finishes on the surfaces that simulate being tiles for indinated roofs, which are molded and their conformation is different to structural panels. NLE patent 90201298, EURO9900522 refers to a panel based on thermoplastic synthetic resin. Spanish patent document ES P 9800369, 19980223 refers to a type of light panel for construction, made from cement mortar. The invention disclosed in the patent ES U 9900014, 9900105 relates to a complex panel of enclosure for construction. It is a panel consisting of cement mortar and other elements Finally the patent ES U 9500616, 19950308 offers a kind of lightweight prefabricated panel for construction. It is a lightweight panel of natural stone with metal armor. Some North American patents with some relation to our invention, to use materials similar to those specified here, do not really have technical-economic objectivity in the optimization of the raw material, nor in the competitiveness, since our process is continuous and very versatile for The product design based on the expectations of the users. This is the case of the US patents Nos. US 6,429,157; US 5,968,641; US 5,625,999 and US 4,418,108, mainly. It is a world-known fact that within the field of construction, that an insulating panel of these materials in the form of foamed polyurethane sand and its faces of glass fiber and polyester resin, has a high level of mechanical resistance and can be used in a very wide range of structural applications, including those where compliance with codes and / or norms of resistance to fire propagation is required.
The need to produce panels at a high production scale is due to economies of scale, for use in a wide range of shapes, dimensions, applications, finishes and / or finishes, and to increase competitiveness against similar conventional products and to guarantee the high quality of the product, where the degree of integration of thermosetting resins is much higher than that achieved by conventional methods, increasing the competitiveness of the product in its market, due to the high quality obtained and the low cost of it. It is therefore an object of the present invention to provide a sandwich panel for mainly structural applications. Still another object of the present invention is to provide a sandwich structural panel based on laminated faces and foamed polyurethane center with high mechanical strength, thermal and acoustic insulation and with high specification of resistance to fire propagation. Still another object of the present invention is to provide a structural sandwich panel made of "composites", for use in a wide range of shapes, dimensions, applications, finishes and / or finishes. Another of the additional objects of the present invention is to provide a method for the manufacture of a sandwich panel, which can be implemented in a continuous manner where the degree of integration of the thermosetting resins is much higher than that achieved by conventional methods. BRIEF DESCRIPTION OF THE FIGURES. To understand the features of the invention, the following figures are illustrative and not limiting of some of the embodiments of the present invention. Figure 1 (a) comprises a general perspective view of a segment of the structural and modular panels of the present invention in a trapezoidal embodiment. Figure 1 (b) represents a general perspective view of a segment of the structural and modular panels object of the present invention in a wavy mode. Figure 2 shows a simplified flow chart of the procedure for panel production structural sandwich type object of the present invention. Figure 3 represents a perspective diagram of the way in which the step of the method of the present invention can be carried out consisting of the formation of the reinforcements in a shelf. Figure 4 represents a perspective diagram of the way in which the step of the method of the present invention can be carried out consisting of the placement of the screens or surfaces of the panel. Figure 5 represents a perspective diagram of the manner in which the step of the process of the present invention comprising a resin bath of the screen reinforcement assembly can be carried out.
Figure 6 represents a perspective diagram of the manner in which the step of the process of the present invention comprising in the pultrusion of the panel in a die can be carried out. Figure 7 depicts a perspective diagram of the manner in which the step of the process of the present invention comprising emptying or injecting the center of the sandwich into a containment press can be carried out. Figure 8 represents a perspective diagram of the way in which the assembly of the panel object of the method of the present invention can be pulled. Figure 9 represents a perspective diagram of the manner in which the step of the process of the present invention comprising the injection of the foamed material in the center of the sandwich, in a polyurethane injection system, can be carried out. represents a perspective scheme of the manner in which the step of the process of the present invention comprising the post-curing of the produced panel can be carried out. Figure 11 represents a perspective schematic of the cutting area of the method of the present invention. DETAILED DESCRIPTION OF THE INVENTION The object of the present invention comprises a process for the transformation of materials and supplies susceptible to be combined with each other by a process modality known as "modified pultrusion". In accordance with the present invention, the process comprises an injection foaming by means of which products known as "composites" are obtained, with the variant being based on thermoset resins in a continuous process. The procedure allows to obtain panels, particularly designed and focused for the construction area, in a wide range of structural applications, such as: roofs, facades, exterior walls, interior walls, divisible walls and decorative panel, among other applications, used in the construction of shopping centers, cultural and recreational centers, housing complexes, schools, hospitals, hotels, industrial warehouses, restaurants, and all areas where there is a need to roof, divide and decorate. By means of the process of the present invention materials with qualities that advantageously allow to be used for their versatility in their finishing are obtained; color and texture, for different designs and architectural finishes; high thermal and acoustic insulation, high resistance to corrosion and weathering (UV rays), highly hygienic-antibacterial, high resistance to chemical vapors, high load resistance, high quality panel formation, to be continuously produced; fire retardant in various degrees, until it reaches the flame-extinguishing; light; practically free of maintenance; ease of installation as its design allows easy assembly to assemble and disassemble; and in general it is allowed to replace conventional sheets and panels such as steel, cement, asbestos, cardboard, etc. The method for continuously producing a sandwich structural and modular panel, both objects of the present invention, comprises, in accordance with the first step of Figure 2, in one or more shelves, of which one of the modalities is shown in FIG. Figure 3. In this type of shelf is available the raw material (3.1) of the reinforcements, preferably it is fiberglass placed in coils of threads known as "roving" type (3.2) on reels that can be vertical or horizontal , according to the convenience to direct the alignment of the same through different screens. These reinforcements serve as guides of formation, same that are conforming the figure of the upper and lower profile of the panel which also correspond to the external and internal faces of said panel. One more form of this type of reinforcements is some types of fiberglass in the form of: rolls type "mat" (3.3); veils, or the so-called "mat", including the so-called synthetic fabrics. All the above according to the sequence and form of construction of the thicknesses of the upper and lower sheets. Once the formation of the reinforcements has been formed, the material follows a second step, whose preferred modality of how to carry it out is shown in Figure 4. The purpose of this part of the procedure is to incorporate the reinforcement formed in the previous part of said process, a series of screens (4.1) that are preferably manufactured from a polymeric material such as high density polyethylene (nylamid), and are intended to be shaping and guiding the figure of the profile to be manufactured , serving in turn to give correct tension to the threads (4.2) of the reinforcements. These templates, once incorporated into the reinforcement, shape in a very precise way the figure and the profile of the panel to be produced. Next, the template and reinforcement assembly passes through the next part or step of the process (Figure 5), which consists of impregnating, preferably with an unsaturated polyester resin composition, said reinforcements. To give better consistency to this "resin bath" (5.1), while these are passing through rollers (5.2) of advance, excess resin is removed so that it is only impregnated with the right amount and adequate ( 5.3), acting as a form of squeezing. The next part of the process is carried out in the manner shown in Figure 6. It is in this part of the process that the preform of the panel profile is given. This part of the process is a die or mold (6.1), in this case pultrusion, giving shape to the set of materials and compositions from the previous stages or modules. It must be taken into consideration that it is in this mold or die that the polymerization reaction of the polyester resin is initiated and completed until the profile of the panel is fully formed on its upper and lower surfaces or sheets. It is in this part of the process where the upper and lower elements of the so-called "sandwich" have already been obtained. The next part of the process is the one shown schematically in Figure 7, which comprises the injection of the internal foamed material of the panel object of the present invention, which is carried out in a containment press (7.1). In this press is where the available space between the faces or upper and lower surfaces of the panel is filled, coming from the previous steps of the process of the present invention. In accordance with said process, the filling is carried out using a foamed material, preferably polyurethane. This filling of foamed material is conveniently directed through emptying nozzles that control the position, direction and resistance of the injection foaming application of the polyurethane. It can be said that the panel formed by their respective faces and with e! desired profile, and with the internal foamed material is fully formed at this point. As can be seen, the movement of the materials and their passage through all the stages of the process, including their formation by the passage of a mold or desired shape, can not be achieved without inducing the passage of said materials through the application of a driving force. . Unlike other processes, such as those for the production of polymer profiles that are based on the principle of applying a force to induce the passage of the material prior to passing through the die or mold (thrust or extrusion), the process of present invention is based on the principle of application of force to pass materials through the molding point, but after passing through it (pull or pultrusion). This "jale system" can be achieved based on a system of hydraulic, pneumatic or other type of force, which allows the manufactured product to be handled, guided, directed and controlled by removing it from the die at a constant speed and continuously. The way to perform this "pulling", in accordance with one of the embodiments of the present invention, is carried out by means of the action of one or more devices or trolleys (8.1) and (8.2) using clamping elements of the material to be pulled, as they are. clamps. The action of both elements or trolleys can be synchronized alternately so as to have continuity and uniformity in the jale force applied. One modality is that when a first car (8.1) holds the piece or profile through the clamps, moving immediately at a continuous speed. Before finishing the maximum displacement limit distance, the second trolley (8.2) also holds the piece and once the first one arrives at its displacement limit, this second trolley keeps pulling on the piece while the first one returns to the starting point and so on Although the above-described method can be carried out successfully in batches, the preferred embodiment and which is precisely the fundamental objective of this invention is the characteristic of carrying it out at a constant speed and continuously. For this it is convenient to use the devices and means of mechanical and electronic synchronization suitable, which allow to vary speeds and forces applied so as to have the necessary versatility for different types of panels, profiles and qualities that are required. Said means and mechanical and electronic devices and of automation can be conveniently selected from those conventionally available in the market. Injection system As already noted, one of the most important aspects for the fulfillment of the purposes of the present invention, is the particular characteristics of the injection system or module of the intermediate foamed element between the two upper and lower surfaces of the panel object of the present invention. In accordance with what is shown in Figure 9, a schematic of one of the preferred embodiments of the foaming injection system is provided. The design of the nozzles allows orienting the convenient dosage of polyurethane (9.1) to fill the gaps that are formed between the wrapping of the upper and lower sheet, this dosage is preferably done using a simple injection head (9.2), making the modifications required in the length of nozzles placed at exact strategic points for the supply of the foaming mentioned. In the general case of foaming by injection, the constituent elements of polyurethane will be used; a poiiol mixture (9.3) and an isocyanate (9.4), which by high pressure in a mixing chamber (9.5) and by the effect thereof, said mixture circulates through a calibrated conduit (9.6) to an outlet, which it coincides eventually with the hole of a casing or hollow that has to be filled and that has been calculated in advance, in order to obtain the complete homogeneous and necessary sealing that determines the properties of the product. Once the polyurethane injection is started, the transfer system follows its constant speed course and continues to carry the panel, which is almost already manufactured, to the eighth module, Fig 10, called the "post-curing" module, where a booth is located (10.1), kiln-type, which optimizes the polymerization quality of both polyurethane and unsaturated polyester with its reinforcements, based on radiation produced by spotlights (10.2) of UV light and / or electrical resistances. Leaving the product of the post-curing module, the product transfer system enters it to the last part of the process, which is the ninth module, called cutting, Fig. 11. In this stage the automatic cutting is performed at the desired length of the panel or the corresponding panels, the cutting is also done by means of a specialized cutting system, since the operation is carried out with the product at constant speed and continuously.