WO2010124804A1

WO2010124804A1 - Continuous method for producing a hollow chamber profile; use of the hollow chamber profile as a frame for windows, doors, and wall coverings

Info

Publication number: WO2010124804A1
Application number: PCT/EP2010/002441
Authority: WO
Inventors: Michael Merkel; Norbert Eisen; Peter Orywol
Original assignee: Bayer Materialscience Ag
Priority date: 2009-04-30
Filing date: 2010-04-21
Publication date: 2010-11-04
Also published as: DE102009019331A1

Abstract

The invention relates to a continuous method for producing hollow chamber profiles in which the hollow chambers are foamed in pack online with plastics, preferably polyurethane. The invention further relates to using the hollow chamber profile as a frame for windows and doors.

Description

CONTINUOUS METHOD FOR PRODUCING A HOLLOW CHAMBER PROFILE;

USE OF THE HOLLOW CHAMBER PROFILE AS FRAME FOR WINDOW,

DOORS AND WALL CLADDING

The invention relates to a continuous process for the production of hollow chamber profiles, in which the hollow chamber is foamed with plastics.

Hollow-chamber profiles can be found today in many areas, such as in housing construction, in windows or in the automotive sector. In order to reduce or avoid the air convection occurring in the hollow chambers and the resulting heat flow, the space in which the air can circulate is kept as small as possible. This can and is currently achieved by the following measures:

a) incorporation of inserts for reducing the hollow chamber;

b) changing the extruded die by dividing the hollow chamber into several small ones

chambers;

c) foaming the hollow chamber after the production of the hollow chamber profile:

d) foaming the hollow chamber during the production of the hollow chamber profile.

Disadvantage of the measures a) to c) is that they are technically very complex and therefore expensive. In addition, they are time consuming and require additional work steps. The measures according to d) are described in DE-A 28 44 006 and EP-A 1 019 607. The disadvantage here is that the liquid foam mixture meets directly on the still very hot surface of the newly formed, extruded profile. This has the effect that the foam structure very bad and the large pores do not bring the desired, optimal insulating effect / stiffening. This is taken into account in DE-A 199 61 306 and DE-A 1 959 464 in that the foam mixture is introduced by means of a lance which protrudes so far into the profile that the foam is first introduced at a cooler point of the profile. The disadvantage here is that the fixed lance heats up, which in turn leads to uncontrolled foaming conditions and on the other hand, the lance clogged by the reactive mixture, so that frequent cleaning or frequent replacement of the lance is required. The cost of cleaning and the loss of raw material is not sustainable and when using solvents for cleaning, there is also an environmental burden.

It was therefore an object to provide a technically simple, continuous method for producing hollow-chamber profiles, which makes it possible to produce a profile with reduced air convection and additional stiffening. Due to the reduced air convection better thermal insulation of the profile is achieved. This object could be achieved by the method according to the invention, in which a carrier material is used, so that the foam first pre-reacts on the carrier material and comes into contact with the ever further cooled surface of the extruded profile at a later time of the foaming process.

The invention thus relates to a continuous process for the production of hollow chamber profiles, which is characterized in that

a) plastic granules are continuously passed through a heated screw (preferably 180 to 250 ⁰ C) in the extruder head of an extruder and melted there, wherein in the extruder head by a corresponding die of an outer wall and a core, the hollow chamber profile is formed,

b) the plastic melt is pressed through this die and at the end the hollow chamber profile made of plastic leaves the extruder head,

c) the profile is cooled,

d) simultaneously with a) in a mixing head the reaction components for a liquid reaction mixture, preferably polyurethane reaction mixture, are mixed continuously,

e) the liquid reaction mixture from d) is poured continuously onto a support material and this support material together with the reaction mixture

f) at the same speed in which the Holhlkammerprofil is extruded, is passed through a channel in the core of the die in the extruder head in the hollow chamber of the hollow chamber profuse,

g) after the extruder head, the reaction mixture within the hollow chamber profile on the carrier material from e) foams and fills the hollow chamber.

The carrier material remains in the hollow chamber profile.

The carrier material used should preferably be designed such that the applied liquid does not run down the edges before the beginning of the foaming process. This means that it should preferably have a certain inherent rigidity. Different shapes are also conceivable (eg U-V or O-shape). In a preferred embodiment, the carrier material is in the form of a band that is formed into a profile by folding prior to application of the foaming material. The carrier material is conveyed at a speed adapted to the withdrawal speed of the extruded profile below the mixing head at which the liquid polyurethane Reaction mixture is applied, led and then transported through an opening in the extruder die into the newly formed Hohlkammerprofϊl.

The used carrier material may e.g. made of plastic, paper, fabric, fibers or preferably cardboard.

The temperature of the extruder head is preferably from 140 to 220 ⁰ C, more preferably at

150 to 200 ^° C. In one embodiment of the method, the core of the extruder head can be cooled so that on the one hand the hollow chamber profile produced in the extruder head already achieves a certain strength and, on the other hand, the reaction of the PU reaction mixture passed through the core of the extruder head on the support material not too heavily influenced. In a further embodiment, excess foam material can be stripped by a device before entering the hollow chamber.

The continuously drawn from the extruder head hollow section is drawn through a water bath and thereby cooled. After a predetermined withdrawal length (determined by the reaction time of the foam and the resulting compaction pressure), the profile is cut to length. The preferred withdrawal speed for the profiles is 0.5 to 3 meters per

Minute.

The die in the extruder head contains a core which, for carrying out the method according to the invention, has a channel for passage of the support material with the reaction mixture. This channel also serves as pressure equalization.

The reaction mixture is preferably adjusted so that it foams only at a distance from the extruder head, in which the hollow chamber profile is already slightly cooled and thus has a certain stiffness / strength. In addition, the distance must be large enough to avoid back-foaming of the reaction mixture to the extruder head.

The selection of the reaction components of the liquid reaction mixture has a direct influence on the properties of the PU foam in the hollow chamber profile. The components used are preferably polyether polyols which are reacted with organic isocyanates. The use of foam stabilizers has proved to be advantageous. As blowing agents physical blowing agents and / or chemical blowing agents, such as water are used. In addition, the reaction mixture may preferably be loaded with air in order to optimize the foam quality / cell structure. - -

In the following, a preferred composition of the reaction mixture is described by way of example:

a) organic and / or modified organic polyisocyanates and / or polyisocyanate prepolymers. Preference is given to di- or polyisocyanates of the diphenylmethane series which have an NCO content of from 20 to 35% by weight. Urethane resp.

Modification products of these isocyanates having carbodiimide groups and / or allophanate or biuret groups are suitable

b) at least one polyol component having an OH number of 20 to 1050, preferably 200 to 900, and a functionality of 2 to 6, or a mixture of polyol components having a calculated average OH number of 250 to 650, preferably 350 to 580, and a computational average functionality of 2.5 to 5, preferably 3 to 4.5,

c) at least one foam stabilizer,

d) water and / or physical blowing agents,

e) optionally fillers,

f) optionally amine catalysts and / or metal catalysts,

g) optionally adjuvants and / or additives, e.g. Flame retardants, adhesion promoters or viscosity-reducing additives.

With the method according to the invention continuously hollow chamber profiles are produced in a simple way, the hollow chambers are foamed online with a polyurethane foam.

The hollow chamber profile produced in this way has a very good thermal insulation and rigidity.

In Fig. 1, the cross section through the extruder head is shown. The core (3) and the outer wall (1) define the gap (2) through which the plastic melt is pressed. Through the channel (4), the carrier material with the polyurethane reaction mixture is introduced into the hollow chamber of the profile.

In Fig. 2 is a side view is shown. The plastic granulate is filled in the extruder head (3) and pressed with melting forward through the die (5). At the same time, a carrier material (1) with the reaction mixture (2) in a speed adapted to the withdrawal speed of the extruded profile through the extruder (4) and through the die (5) in the newly formed hollow chamber profile (6). This is where the cooling of the - -

Profiles e.g. through a water bath (not shown). The newly created profile is supported from the outside (7). The foam now rises above the edge of the carrier material (8, 9) and foams the hollow chamber. After a predetermined length, at which the filling foam no longer nachdrückrückt, the profile is cut to length (10).

These hollow chamber profiles are preferably used as frames for windows and doors and as wall cladding.

Claims

- Patent claims

1. A process for the preparation of Hohlkammerprofϊlen, characterized in that

a) plastic granules are continuously fed via a heated screw into the extruder head of an extruder and melted there, wherein the hollow chamber profile is formed in the extruder head by a corresponding matrix of outer wall and core,

b) the plastic melt is pressed through the die and at the end the hollow chamber profile of plastic leaves the extruder head,

c) the profile is cooled,

d) simultaneously with a) in a mixing head, the reaction components for a liquid

Reaction mixture are mixed continuously,

f) at the same speed at which the Holhlkammerprofil is extruded, through a channel in the core of the die in the extruder head in the hollow chamber of

Is directed hollow chamber profiles,

2. Use of the hollow chamber profile produced according to claim 1 with improved thermal insulation properties and / or reinforcement as a frame for windows and doors and wall cladding.