Continuous production of profiles in a sandwich type of construction with foam cores and rigid-foam-filled profile

Abstract

The present invention relates to a novel process for the production of novel fiber-reinforced profile materials comprising a rigid foam core, in particular a PMI foam core. In particular, the present invention relates to a novel process which can be carried out in two variants, a short Pul-press process and a Pul-shape process. One step here produces a fiber-reinforced profile material and simultaneously inserts the rigid foam core into same. The same step moreover ensures very good binding of the rigid foam core to the fiber-reinforced profile material.

Claims

1. A process for continuous production of fibre-reinforced profiles comprising a foam core, the process comprising: a) introducing foam cores and connecting a newly introduced foam core to an end of the most recently introduced foam core; b) wrapping a fibre material around the foam core; c) impregnating the fibre-material wrap with a resin; d) optionally moulding the wrapped foam core in a first mould; e) heating and thereby optionally hardening the resin in a second mould; f) cooling the wrapped foam core in a third mould; and g) separating individual profiles by cutting or sawing and removing the finished workpiece, wherein the second and third mould are moved in respectively mutually opposite direction on carriages.

2. The process according to claim 1, wherein the foam core takes the form of a plurality of successive individual pieces when it is continuously passed into a pultrusion plant, and the individual pieces are connected to one another by adhesion bonding or insertion or through addition of a coupling piece.

3. The process according to claim 1, wherein the fibre material is carbon fibres, glass fibres, polymer fibres, or textile fibres.

4. The process according to claim 1, wherein the resin is a thermoset.

5. The process according to claim 1, wherein the fibre material is in the form of individual fibres, rovings, non-wovens, woven fabrics and/or laid scrims.

6. The process according to claim 1, wherein the foam core is a core comprising poly(meth)acrylimide.

7. The process according to claim 6, wherein polymethacrylimide in the density range from 30 to 200 kg/m.sup.3 is used as material for the foam core.

8. The process according to claim 1, wherein the fibre material in the wrapping is a prefabricated preform made of the fibre material.

9. The process according to claim 1, wherein the process is conducted as Pul-press process in which a) to g) take place in moulds or, respectively, devices that are separate from one another.

10. The process according to claim 1, wherein the process is carried out as Pul-shape process in which the first and the second mould are the same mould, in which c), d) and e) are carried out simultaneously.

11. The process according to claim 1, wherein the fibre material is aramid fibres.

12. The process according to claim 1, wherein the resin is a thermoset comprising a material comprising a polyester resin, a vinyl ester resin, a phenolic resin, a PU resin, an epoxy resin, or any combination thereof.

13. The process according to claim 1, wherein the resin is a thermoset comprising a material comprising a PU resin or an epoxy resin.

14. The process according to claim 1, wherein the wrapping is carried out with rotating winding equipment.

15. The process according to claim 1, wherein the wrapping is wrapping a plurality of various layers of the fibre material around the foam core in a braid structure.

Description

EXAMPLES

(1) Continuous production of a complex fibre-composite profile with a rigid PMI foam core:

(2) ROHACELL? IG-F 51 foam cores are cut to size to give elongate rectangular shapes and then introduced continuously by a guiding system into the plant. In a step that follows, these are sheathed with dry and presaturated fibres: unidirectionally 90 fibres each 1600 tex (Toho Tenax T1600) and 48 fibres each 800 tex (Toho Tenax T800). In the preform mould all of the materials are consolidated and subjected to final saturation with a vinyl ester resin. The fibre-composite material (pultrudate), not yet hardened, is then continuously drawn into a displaceable and heatable compression device (compression device number 1) by way of a compression device for cooling (compression device number 2). The shaping and hardening then take place here. The hardening time is kept short by using a temperature suitable for these materials: 120? C. As soon as the profile has hardened, compression device number 1 reaches its end position. Here, the cooling compression device takes over the complex profile and in doing so continues the drawing of the pultrudate. While this happens, the opened compression device number 1 can travel back to its starting position, and the cycle begins again.

KEY TO THE DRAWINGS

(3) FIG. 1 shows by way of example a diagram of the construction of a plant suitable for the Pul-press process according to the invention. Key to FIG. 1 below:

(4) (1) Foam core (available stock)

(5) (2) Foam core (introduction into plant and connection to end of previous foam core)

(6) (3) Introduction of fibre, unidirectional

(7) (4) Winding, braiding device

(8) (5) Resin impregnation

(9) (6) Resin reservoir (in this case 2-component system with components A and B)

(10) (7) Preforming mould

(11) (8) Carriage-type heating mould

(12) (9) Carriage-type cooling mould

(13) (10) Displacement system with drive for moulds (8) and (9)

(14) (11) Cutting device

(15) (12) Finished profile

(16) (13) Handling system for profile (12)

(17) (14) Storage system

(18) FIG. 2 shows by way of example a diagram of the construction of a plant suitable for the Pul-shape process according to the invention. Key to FIG. 2 below:

(19) (101) Thermoformed/moulded foam core (available stock)

(20) (102) Coupling piece (this variant can also be used in the embodiment according to FIG. 1)

(21) (103) Foam core guide system (analogous to (2) in FIG. 1))

(22) (104) Introduction of fibre, unidirectional, and also winding, braiding device (analogous to FIG. 1, (3), (4))

(23) (105) Guiding system for dry semifinished product

(24) (106) Mould with resin infiltration, with optional further shaping, heating and attached resin reservoir (in this case 2-component system with components A and B); this mould assumes the functions of the moulds (5), (7) and (8) in the embodiment according to FIG. 1

(25) (107) Carriage-type cooling mould

(26) (108) Cutting device

(27) (109) Finished profile

(28) (110) Handling system for profile (109)

(29) (111) Storage system

(30) In connection with the drawings it should be noted that these are merely diagrams of the respective embodiments. The carriage on which the first and the second mould are moved is naturally markedly longer, in order to realize an adequate transport path and thus an adequately long heating and, respectively, cooling process. The precise length will be calculated by the person skilled in the art in particular from the operating speed, the thickness of the outer layer and to the properties of the resin used.