DE102006024940A1 - Production of article such as tube or disk elements out of foam material, comprises supplying thermally activable pre-foamed plastic granulates mixed with binder and/or coating material into a mold and thermally activating the mixture - Google Patents

Abstract

The production of article such as tube or disk elements out of foam material, comprises supplying thermally activable pre-foamed plastic granulates mixed with binder and/or coating material into a mold for hardening and thermally activating the mixture of plastic granulates and binder and/or the coating material by heat of electromagnetic microwave radiation for foaming. The article is formed with a shaping contour of the mold. Resin and/or varnish are supplied into the mold for foaming thermally activable plastic granulates. The production of article such as tube or disk elements out of foam material, comprises supplying thermally activable pre-foamed plastic granulates mixed with binder and/or coating material into a mold for hardening and thermally activating the mixture of plastic granulates and binder and/or the coating material by heat of electromagnetic microwave radiation for foaming. The article is formed with a shaping contour of the mold. Resin and/or varnish are supplied into the mold for foaming thermally activable plastic granulates. The binder and/or coating material is distributed over shaping contour surface area into the mold through rotation of the mold. The mold in rotation is transferred during pre-foaming of the plastic granulates. Independent claims are included for: (1) an article produced through mold foaming of thermally activable material; and (2) procedure for pre-foaming thermally activable plastic granulates for foaming.

Description

The The invention relates to a method for producing an article from a foam-containing material.

Items out Foam and various processes for their preparation are known in various variants. As foams come z. Polystyrene, Polypropylene, polyurethane or polyethylene used, also in so-called molding processes.

One Known method is the so-called. Styrofoam process, in which expanded Polystyrene (PS-E) is produced by physical foaming. In a conventional process variant is blowing agent-containing Granules of polystyrene by heating with steam initially prefoamed and thereby expanding to a multiple of the original volume. The pre-expanded material is then stored and finally placed in a mold, the shape being almost complete filled becomes. When ready foaming will that be prefoamed PS-E by further heating to z. B. expanded about 130 ° C with steam, so that the material continues to inflate and thus a corresponding high pressure arises in the closed mold. The used Particles merge or stick together at their edges and form a coherent one Body, its outer contour the shaping contour corresponds to the shape. The subject in question made of polystyrene can then be removed from the mold and its Use supplied or optionally further treated, such as coated or cut.

Polystyrene moldings be u. a. as a shock-absorbing Packing elements or as elements for thermal insulation and / or sound insulation ver used. Foam polystyrene is also used as a building material in model making.

adversely to the previous methods for the production of foam bodies or objects Made of a foam-containing material is that they both equipment and time consuming and relatively much energy require.

• a) Bereitstellen eines thermisch zum Aufschäumen aktivierbaren Ausgangsmaterials, insbesondere Kunststoffgranulates,
• b) Einbringen des Ausgangsmaterials in eine Form und
• c) thermisches Aktivieren des Ausgangsmaterials mittels Strahlung, insbesondere mittels elektromagnetischer Mikrowellenstrahlung, um das Ausgangsmaterial in der Form zu verschäumen und dabei einen Gegenstand mit der Formgebungskontur der Form auszubilden.

The invention has for its object to provide a contrast simplified method for producing an article from a foam-containing material. The method according to the invention comprises the steps:

• a) provision of a thermally foamable starting material, in particular plastic granules,
• b) introducing the starting material into a mold and
• c) thermally activating the starting material by means of radiation, in particular by means of electromagnetic microwave radiation, in order to foam the starting material in the mold and thereby to form an object with the shaping contour of the mold.

According to one Process variant, the process can be multi-level in terms of Run off foaming, namely with a pre-foaming stage, in which the material used in a Vorschäumform preferably already is activated by means of microwave radiation for pre-foaming. As starting material In particular, polystyrene in particulate form and with added blowing agent, about pentane, in question. The pre-expanded material can then as Starting material for the finished foam process used in the mold for the preparation of the subject matter become. According to one another variant of the method, the pre-foaming and the finished foaming takes place in one and the same form. It can be provided that the Form means of implementation a gas exchange, in particular means for gas discharge and air supply.

Preferably the activation of the starting material takes place by foaming Heat of the starting material with microwave radiation, which is the starting material interspersed in the mold and heated.

The extensive activation of the starting material by means of superheated steam, as is common in the art was, can be omitted. This should not be excluded be that for moistening the starting material water or water vapor can be introduced into the mold and z. B. during thermal activation is heated by means of microwave radiation. The introduction of water in the form and heating of the water by means of microwave radiation in the presence of the starting material in the mold, foaming can accelerate. It may be advantageous to move the mold, in particular to turn around a horizontal axis.

According to one particularly preferred embodiment The invention uses a starting material comprising polystyrene particles. Unless the starting material essentially exclusively Polystyrene particles and optionally a propellant, such as pentane, exists, creates a foamy shape Foam polystyrene article (styrofoam).

The Process according to the invention is therefore suitable for the production of Styrofoam items with a variety of shapes, including blocks, hollow bodies, plates, model components etc.

A very interesting and the scope of the invention still considerably Enlargement variant of the method is characterized in that in addition to thermally foaming activatable starting material, a fluid, curable binder and / or Coating material, in particular a resin or / and a lacquer, is introduced into the mold.

This can z. B. in such a way that the binder and / or Coating material before the thermally activatable for foaming Starting material introduced into the mold and shaping contour areas is distributed in the form. Distributing the binder and / or coating material can by moving the mold, in particular by turning or tumbling the shape supports be depending on the shape and speed of movement centrifugal forces and / or gravity for support the distribution effect of free-flowing or liquid Binder or / and coating material is used. there It may be provided that the binder or / and coating material subjected to a Vorverfestigungsprozess until the viscosity of the binder or / and coating material is sufficiently large that it is at least approximately in the desired Distribution remains on the shaping contour surface areas of the mold and form a layer there. The pre-consolidation process can ever after the binder or / and coating material chemical or physical nature. For the chemically curable Materials may be z. B. be two-component binder, their components before entry into the mold or only in the form together be to react with each other and thereby to a solidification of the multicomponent mixture lead. Physical curing can z. B. take place under the action of radiation, depending on the used Binder or / and coating material optical irradiation, such as in photopolymers, or microwave irradiation a curing effect triggers. The chemical and / or physical curing process may, if necessary, be further enhanced activities be accelerated, for example, by heat both directly as also indirectly or further irradiation, if necessary also outside the Shape.

Provided the binder or / and coating material already used originally a sufficient viscosity has that it can adhere to the shaping contour areas a Vorverfestigungsprozess of the material also be omitted. In a further step then takes place the filling of the thermally foaming activatable starting material into the mold and its activation by the microwave radiation, so that the mold cavity filled by the material and under the expansion pressure a coherent foam article with outer layer is formed from the binder and / or coating material. It may well be desirable be that the binder or / and coating material during the foaming process dissolved so that it sticks to the foamed material. Provided required, still another irradiation step or the like. for solidifying the outer layer of the manufactured article.

The Binder or / and coating material may be used in the curing process in the form or possibly outside to be subjected to the mold. As a binder or / and coating materials come numerous materials, especially organic materials, in question, such. As well as epoxy resins, paints and the like.

A Another variant of the method provides that the binder and / or Coating material preferably in a premix together with thermally foaming activatable starting material is introduced into the mold. The foaming process by microwave activation of the starting material then results to form a foam article whose structure is soaked with the binder or / and coating material. As thermal for frothing Activatable starting material is particularly preferred Way the already mentioned polystyrene granules, in particular with propellant. It thus arises when carrying out the last-mentioned variant of the method of the binder or / and coating material interspersed styrofoam molding, wherein the binder is preferably at the end of the foaming process towards a curing process undergoing chemical treatment according to the material use Nature and / or physical nature. This can be this Curing Process according to a Process variant triggered by micro wave radiation or be accelerated. This can be microwave radiation with a special on the curing behavior of the binder and / or coating material tuned wavelength or possibly also be the microwave radiation, by means of which the starting material for frothing is activated. There are also alternative Aushärtprozesse in question, such as Irradiating the manufactured article with light, such as UV light, or thermal curing.

Also in the variant of the method with co-introduction of the binder and / or coating material as well as the thermally foaming activatable starting material, the mold is preferably moved during the foaming of the starting material, in particular in rotary motion or tumbling motion. As a result of the movement, due to the effect of gravity or / and possibly centrifugal action, it is possible for the binder or / and coating material to collect on the shaping contour surface areas, ie on the inner mold walls with greater concentration relative to the foam, than in central regions of the mold cavity is. In this way, the article can obtain a surface zone consisting almost exclusively of the binder and / or coating material. Finally, since the cured binder or / and coating material has greater mechanical strength than the foam filler material embedded therein and has a finer surface finish, the article produced will have a mechanically and preferably also chemically stable and, moreover, sizable surface.

ever after process management However, it can also be achieved that a segregation between the binder / coating material and the foam material in the form does not take place, so that the manufactured object finally one homogeneous microstructure Has.

The inventive method is suitable for the production of objects of almost any shape designs, so z. B. also for the production of fluid line elements, in particular Tubes for conducting gaseous and / or liquid Substances. It is also suitable for the production of panel elements with insulating regions of foam, wherein as a binder and / or Coating material also inorganic materials, such as cement based materials come into question, about with wall elements internal insulation made of foam.

Farther the method is suitable for the production of housing parts, Vehicle body parts, vessels etc. Also, the method is suitable for producing block foams, which then further processed can be z. B. by sawing too Plates or moldings.

Under Protection is also provided by a respective object one of the claims 16 to 18 and a Vorschäumverfahren according to claim 19.

The The invention will be explained in more detail below with reference to FIGS.

1 shows sectional views of five wall sections A ... E, which can be produced by the method of the present invention.

2 shows a tube in cross-section, as can be produced by the method of the present invention.

The wall section A in 1 is a section of styrofoam plate that can be made by the process of the present invention without the addition of binders and / or coating materials. Such plates can z. B. for heat insulation, sound insulation, etc. are used.

With B is in 1 a Styrofoam wall portion shown on one side a surface layer 2 which serves as a protective layer and gives the wall on the coating side a handsome design. The layer 2 exists z. B. from a paint which has been used as a coating material in the implementation of the method.

The wall section C off 1 differs from the wall portion B in that it has a respective surface layer on both wall surface sides 2 from a coating material. With 1 is the styrofoam substrate area designated.

For wall sections B and C in 1 is a relatively abrupt transition from the coating 2 to the styrofoam base substrate 1 available.

In the wall portion D, the binder or / and coating material-free styrofoam substrate region is 1 limited to a relatively narrow center zone, starting from which increases on both sides of the wall, the concentration of binder. In the transition areas 3 the wall section D thus consists of a hardened Styrofoam binder or / and coating material mixture.

The wall section E in 1 contains in addition to the foamed polystyrene, a substrate passing through the base binder or / and coating material. By the amount ratio between polystyrene starting material and binder and / or coating material, the mechanical properties of the wall section can be influenced.

Although in 1 As examples of the process products according to the invention, simple plates are shown, so objects produced according to the invention can of course also significantly more complicated geometries and optionally have different concentrations of the binder and / or coating material.

2 shows as an example of a hollow body produced by the method of the present invention, a conduit 4 in cross section. The Pipeline 4 has over its pipe wall thickness, a distribution of the added binder or / and coating material, the distribution of the wall portion D in 1 similar. The pipe 4 is by the accumulation of the binder and / or coating material on the surfaces inside and outside with a coating 2 which can provide protection against certain aggressive conduction media and / or against mechanical abrasion or against mechanical deformation. Of course, pipes with other wall structures, such as the structures A, B, C or E from 1 produced according to the invention.

Claims (19)

Method for producing an article made of a foam-containing material, comprising the Steps: a) providing a thermally activatable for foaming Starting material, in particular plastic granules, b) introduction of the starting material in a mold and c) thermal activation the starting material by means of radiation, in particular by means of electromagnetic Microwave radiation to foam the starting material in the mold and to form an object with the shaping contour of the mold. The method of claim 1, wherein the starting material Contains polystyrene particles. The method of claim 1 or 2, wherein the starting material a propellant, especially pentane. Method according to one of the preceding claims, wherein prefoamed the starting material is. Method according to one of the preceding claims, wherein additionally to the thermally foaming activatable starting material, a fluid, curable binder and / or Coating material, in particular a resin or / and a lacquer, is introduced into the mold. The method of claim 5, wherein the binder or / and Beschich material before the thermally activatable foaming Starting material introduced into the mold and shaping contour areas is distributed in the form. The method of claim 6, wherein distributing the Binder or / and coating material by moving the mold, in particular by rotating the mold takes place or at least supported. A method according to claim 5 or 6, wherein the binder or / and coating material a curing process, preferably in is subjected to the mold. The method of claim 8, wherein the binder or / and coating material the curing process before foaming the thermally foaming is exposed to activatable starting material. The method of claim 5, wherein the binder or / and coating material, preferably in a premix together with the starting material which can be thermally foamed is introduced into the mold. The method of claim 5, wherein the binder and / or coating material according to the thermally activatable for foaming Starting material is introduced into the mold. Method according to one of claims 5 to 11, wherein the mold while foaming the starting material moves, in particular offset in rotational movement becomes. Method according to one of the preceding claims, wherein to carry out the step c) of the thermal activation of the starting material a the starting material in the form passing through and leading to its heating electromagnetic Microwave radiation is generated. Method according to one of the preceding claims, wherein it for producing a fluid conduit element, in particular one Pipe, performed becomes. Method according to one of the preceding claims, wherein it is carried out for the production of a plate element. An article produced by foam-foaming a thermally foam-activatable material, in particular polystyrene, in the presence of a preferably organic binder and / or coating material according to one of claims 5 to 13, wherein it has at least one structure ( 3 ) has a penetrated by the binder and / or coating material foam. The article of claim 16, wherein the concentration the binder or / and coating material at least partially from the outer surface of the Object decreases toward its interior. Article manufactured by Formver foaming a thermally foamable material, in particular polystyrene, in the presence of a preferably organic binder or / and coating material according to one of claims 5 to 13, wherein it has a foam internal structure ( 1 ) with layered accumulation ( 2 ) of the binder and / or coating material on its surface. Process for pre-foaming a thermally activatable for foaming Plastic granulates, in particular polystyrene powder with blowing agent, wherein the plastic granules in a Vorschäumbehälter a microwave radiation is exposed to activate it for pre-foaming.