WO2012062684A1

WO2012062684A1 - Composite component comprising a polymer phase and a foamed phase, and method for producing same

Info

Publication number: WO2012062684A1
Application number: PCT/EP2011/069491
Authority: WO
Inventors: Philippe Desbois; Olaf Kriha; Bangaru Dharmapuri Sriramulu Sampath; Holger RUCKDÄSCHEL; Dietrich Scherzer; Freddy Gruber; Klaus Hahn
Original assignee: Basf Se
Priority date: 2010-11-12
Filing date: 2011-11-07
Publication date: 2012-05-18
Also published as: EP2638104A1; JP2014503377A; KR20130113479A; BR112013011727A2; CN103228717A; CN103228717B

Abstract

The invention relates to a composite component comprising a non-foamed polymer phase and a foamed phase, and to a method for producing same.

Description

A composite member comprising a polymer phase and a foamed phase, and methods for producing the same

description

The present invention relates to composite members comprising a non-foamed polymer phase and a foamed phase, and a method for producing the same.

Composite components of at least two different components are known in the art. In the context of the present disclosure, the term "composite component" refers to a component made of two or more bonded materials Examples of conventional composite materials are carbon fiber reinforced plastic or glass fiber reinforced plastic flexible walls are separated.

Examples of foams include:

• Pumice, a porous glassy volcanic rock whose specific gravity is smaller than that of water

Foams, foam rubber, polystyrene as insulation and packaging material

• foam glass

• Aerogels

Metal foams, e.g. Aluminum foam for high strength but lightweight metal structures

· Foam concrete.

A polyamide combined with a foam results in a sandwich foam

Fiber composites.

JP 59169833 A describes a method for producing a composite product, wherein a high-viscosity plastic composition is poured into a mold.

MT Penny, Cellular Polymers (1988), 7 (2), pp. 119-133 describes the preparation of nylon foams by "Reaction Injection Molding" (RIM) JP 63069614 A describes the preparation of a synthetic resin from several layers, wherein the inner layer consists of polyurethane (PU) and the outer layer is based on caprolactam.

JP 7195602 A and JP 2826059 B2 describe molded parts consisting of a foamed core based on PU and an outer layer comprising nylon and carbon fibers, wherein the core and the outer layer are joined together by heating. However, the composites of the prior art, or the processes for producing the same, have certain disadvantages. For example, the previously known materials usually have a relatively high weight. In addition, the materials are usually glued according to the prior art; As a result, the adhesion between different components is often insufficient. In addition, the processes already described sometimes involve the risk of damaging or destroying the foam component during processing due to the high pressure required.

It was therefore an object to further reduce the weight of a composite component in order to provide real lightweight materials, while still ensuring good adhesion between different components and also to maintain as possible the rigidity of the product. In this case, the foam should not be damaged as part of a composite component during the manufacture of the composite component. Surprisingly, the stated object could be achieved by preparing a non-foamed polymer phase by anionic polymerization in the presence of a foamed phase.

The subject of the present invention is thus a process for producing a composite component comprising at least one non-foamed polymer phase (P) comprising polyamide, and at least one foamed phase (G), wherein the non-foamed phase by anionic polymerization at least a monomer (M) selected from the group of lactams is prepared in situ in the presence of the foamed phase (G). Further objects of the present invention are also a composite component, which can be produced by the process according to the invention, and the use of a composite component, which can be prepared by the process according to the invention, as a structural element in the automotive industry.

In a preferred embodiment of the method according to the invention, the foamed phase (G) is closed-cell.

The term "closed-cell foam" as used in the present disclosure refers to foams in which the cells have no pores or disrupted surfaces. In contrast, the term "open-celled" refers to a foam structure defined by each cell being at least In addition, the majority of cell fins must belong to at least three cells, and closed-cell foams are generally based on polyurethane (PU), polyvinyl chloride (PVC), polymethacrylimide (PMI) and polystyrene (PS). (see Arnim Kraatz, Dissertation 2007, University of Halle).

The non-foamed polymer phase (P) according to the invention is preferably prepared by anionic polymerization of at least one lactam monomer via reaction injection molding (RIM). A description of the RIM process for the production of polyamide molded parts and the necessary equipment is found, for. In P. Wagner, Kunststoffe 73 (1983), 10, 588-590 and in P. Schneider et al., Plastics Engineering, 1984, p. 39-41. The at least one monomer (M) is selected in the process according to the invention from the group of lactams. For example, monomers may be used from the group comprising caprolactam, piperidone, pyrrolidone, laurolactam or mixtures thereof. Preference is given to using a monomer (M) selected from the group comprising caprolactam, laurolactam and mixtures thereof.

In addition, up to 50% of lactones, preferably caprolactone, can also be copolymerized with the monomer (M) from the group of lactams.

In one embodiment of the process according to the invention, the anionic polymerization of the at least one monomer (M) is carried out in the presence of a catalyst (K) and / or an activator (A).

Examples of suitable optional catalysts (K) are sodium caprolactamate, potassium caprolactamate, bromide magnesium caprolactamate, chloride magnesium caprolactamate, magnesium bis-caprolactamate, sodium hydrides, sodium metal, sodium hydroxide, sodium methoxide, sodium ethoxide, sodium propoxide, sodium butoxide, potassium hydride, potassium metal, potassium hydroxide, potassium methoxide, Potassium ethoxide, potassium propoxide, potassium butoxide, preferably sodium hydrides, sodium metal, sodium caprolactamate, more preferably sodium caprolactamate (eg Bruggolene® C 10, a solution of 18% by weight of sodium caprolactamate in caprolactam).

Suitable optional activators (A) include aliphatic diisocyanates such as butylene diisocyanate, hexamethylene diisocyanate, octamethylene diisocyanate, decamethylene diisocyanate, undecodecamethylene diisocyanate, dodecamethylene diisocyanate, or aromatic diisocyanates such as tolylene diisocyanate, isophorone diisocyanate, 4,4'-methylenebis (phenyl isocyanate), 4,4'-methylenebis (cyclohexylisocyanate) or polyisocyanates such as isocyanurates of hexamethylene diisocyanate, Basonat® HI 100 from BASF SE, allophanates such as ethyl allophanate or mixtures thereof, preferably hexamethylene diisocyanate, isophorone diisocyanate, particularly preferably hexamethylene diisocyanate. The diisocyanates can be replaced by monoisocyanates. Alternatively Dodecamethylendisäurechlorid, Dodecamethylendisäurebromid and aromatic diacid halide such as Toluylendisäurechlorid, Toluylenmethylendisäurebromid, isophorone rondisäurechlorid, Isophorondisäurebromid, 4.4 are useful as activator aliphatic diacid halides such as Butylendisäurechlorid, Butylendisäurebromid, Hexamethylendisäurechlorid, Hexamethylendisäurebromid, Octamethy- lendisäurechlorid, Octamethylendisäurebromid, Decamethylendisäurechlorid, Decamethylendi- acid bromide, ' Methylenebis (phenyl) acid chloride, 4,4'-methylenebis (phenyl) acid bromide, 4,4'-methylenebis (cyclohexylic chloride, 4,4'-methylenebis (cyclohexyl) acid bromide or mixtures thereof, preferably hexamethylenedioic acid chloride, hexamethylenedioic acid bromide or mixtures thereof, especially preferably hexa methylendisäurechlorid. The diacid halides can be replaced by monoacid halides.

The molar ratio of lactam to catalyst can be varied within wide limits, is usually 1: 1 to 10,000: 1, preferably 10: 1 to 1000: 1, particularly preferably 50: 1 to 300: 1.

The molar ratio of activator to catalyst can be varied within wide limits, is generally 100: 1 to 1: 10,000, preferably 10: 1 to 1: 100, particularly preferably 1: 1 to 1:10.

The foamed phase (G) can be present according to the invention, for example in the form of a cuboid, a sphere, a cylinder or a pyramid.

The foamed phase (G) is preferably made of polyamide (PA). However, the foamed phase can also consist of another material, for example of another plastic, of metal or wood.

In one embodiment of the process according to the invention, the foamed phase (G) forms a cuboid, wherein at least 90%, preferably at least 95% of the surface of a side surface of the foamed phase (G) is covered with the non-foamed phase (P).

In a further embodiment of the process according to the invention, at least 90%, preferably at least 95% of the total surface of the foamed phase (G) is covered with the non-foamed phase (P).

In one embodiment of the method according to the invention, first the foamed phase (G) is introduced into a mold, and then the non-foamed polymer phase (P) is poured into this mold. The polymerization can also be carried out in the presence of crosslinkers.

In this case, it is possible to react a diisocyanate or a diacid halide with a lactam A at a temperature of (-30) to 150 ° C and then react with a lactam B, a catalyst and an activator at a temperature of 40 to 240 ° C. Alternatively, diisocyanate may be replaced by polyisocyanate and diacid halide by polyacid halide.

The polymerization can be carried out in the presence of additives such as fibers or fillers; The fibers are preferably selected from the group comprising glass fibers and carbon fibers. These fibers can serve as fillers and / or reinforcing agents.

Other fillers or reinforcing agents which can be used are, for example, also minerals in customary grain size for thermoplastic applications, for example kaolin, chalk, wollastonite or talc or glass fibers, e.g. As milled glass fibers and textile structures (fabric and scrim) of unidirectional fibers, preferably glass and carbon fibers.

The foamed phase (G) can also be structured, for. B. holes, grooves or notches.

The composite component which can be produced according to the invention can also comprise more than one foamed phase (G) and one non-foamed polymer phase (P). For example, the composite component produced according to the invention may comprise two layers of a foamed phase (G) and three layers of a non-foamed phase (P).

The end product of the process according to the invention, ie the composite component which can be produced according to the invention, preferably has at least 20% by volume of the foamed phase (G) with respect to the entire end product, more preferably at least 50% by volume.

The composite component which can be produced by the process according to the invention can advantageously be used inter alia as a structural element in the automotive industry.

Examples

The following examples serve to illustrate some aspects of the present invention. They are not intended to limit the scope of the present invention.

Example 1: Production of a Foam Block with Polyamide Cover All components and tools were dry.

A closed polyamide (PA) foam with the dimensions 55 ^* 20 ^* 95 mm ³ was placed in a tray of aluminum foil with the dimensions 65 ^* 30 ^* 105 mm ³ . The foam was placed in the foam by means of screws through the aluminum foils so that the foam - shell distance to the bottom and sides was 5 mm. The upper side of the foam was 5 mm lower than the upper edge of the shell. The dish was placed in an oven at 150 ° C under nitrogen.

The following solutions were prepared separately in two glass flasks under nitrogen:

1: 69.2 g of caprolactam + 8.00 g of Brüggolen® C10 (a catalyst for the production of polyamide from Brüggemann, 17% of Na-caprolactam in caprolactam)

2: 69.2 g of caprolactam + 3.53 g of Brüggolen® C20 (an activator for the production of polyamide from Brüggemann, 80% blocked diisocyanates in caprolactam) and mixed by means of a magnetic stirrer. At 1 10 ° C, solutions 1 and 2 were combined, mixed for 15 seconds and then placed in the aluminum tray in the oven Add N2 until the bowl is full. After 10 minutes, the polymerization was over. The aluminum tray was removed from the oven and cooled. The molding was removed from the aluminum tray. It consisted of a foam core and a polycaprolactam shell. VZ (viscosity number) of the shell = 215; Rest caprolactam in the shell: 1, 2 wt.%

Example 2

Example 1 was repeated, but this time the foam was placed on a glass ball and not held with screws to adjust the distance from the aluminum tray. By means of a weight on the foam, it was ensured that the foam remained on the glass ball and did not float upwards.

Example 3

A piece of polyamide (PA) foam measuring 3 ^* 100 ^* 100 mm ³ was placed in a mold measuring 4 ^* 100 ^* 100 mm ³ (injection molding apparatus). The mold was closed and equal volumes of solution 1 and 2 were added, after mixing in a flow mixer, at 120 ° C. The mold had a temperature of 150 ° C. After 10 minutes, the molded part was removed from the mold. It consisted of the foam enveloped with the polylactam.

PA shell: VZ = 180; Residual proportion of caprolactam in the shell: 1.1% by weight Example 4

A sheet of expanded polypropylene (Neopolen® P, a BASF SE PP foam having a density of 80 g / l) was placed in an oven at 120 ° C under nitrogen, and a mixture of solutions 1 and 2 (mixing time 30 seconds ) was poured onto the PP plate at 100 ° C. After 10 minutes, the plate was removed from the oven. The resulting part was a laminate of foamed polypropylene and polylactam. VZ of the shell = 205; Residual content of caprolactam in the shell: 2.9% by weight

Example 5

A plate of Evonik's Rohacell® IG foam was placed in an oven at 120 ° C under nitrogen, and a mixture of solutions 1 and 2 (mixing time 30 seconds) was poured onto the plate at 140 ° C. After 10 minutes, the plate was removed from the oven. Rohacell® IG foam is a polymethacrylimide based foam with a density of 75 g / i.

The resulting part was a laminate of foamed Rohacell® and polylactam.

VZ of the shell = 195; Residual amount of caprolactam in the shell: 1, 5 wt.%

Example 6 A Lantor Soric® XF6 foam sheet from Lantor was placed in an oven at 100 ° C under nitrogen and a mixture of solutions 1 and 2 (mixing time 30 seconds) was poured onto the plate at 140 ° C. Lantor Soric® XF6 foam is a foam based on nonwoven polyester with a density of 600 g / l.

After 10 minutes, the plate was removed from the oven. The resulting part was a laminate of foamed Lantor Soric® foam and polylactam.

VZ of the shell = 223; Residual content of caprolactam in the casing: 2.2% by weight Example 7

A balsa plate is placed in an oven at 100 ° C under nitrogen, and a mixture of solutions 1 and 2 (mixing time 30 seconds) is poured onto the plate at 110 ° C. After 10 minutes the plate is removed from the oven. The resulting part is a laminate of balsa wood and polylactam.

Example 8

A sheet of aluminum foam (Alulight® sandwich panels from Alulight International GmbH, 0.6 mm cover layers, 20 mm total thickness with a density of about 400 g / l) is placed in an oven at 100 ° C under nitrogen , and a mixture of solutions 1 and 2 (mixing time 30 seconds) is poured at 1 10 ° C on the plate. After 10 minutes the plate is removed from the oven. The resulting part is a laminate of aluminum foam and polylactam.

The examples show, among other things, that the materials produced at a lower density (d <0.8) have a very high stiffness, close to pure PA. The stiffness can be determined manually by bending tests; if the samples are not bendable, the stiffness is high.

Claims

claims

A process for producing a composite component comprising at least one non-foamed polymer phase (P) comprising polyamide, and at least one foamed phase (G), wherein the non-foamed phase is obtained by anionic polymerization of at least one monomer (M) selected from the group of Lactame is prepared in situ in the presence of the foamed phase (G).

The method according to claim 1, wherein the foamed phase (G) forms a parallelepiped, and wherein at least 90%, preferably at least 95% of the surface area of a foamed phase (G) side surface is covered with the non-foamed phase (P).

A process according to claim 1, wherein at least 90%, preferably at least 95% of the total surface area of the foamed phase (G) is covered with the non-foamed phase (P).

4. The method according to any one of claims 1 to 3, wherein the non-foamed phase (P) by reaction injection molding (RIM) is prepared.

5. The method according to any one of claims 1 to 4, wherein the foamed phase (G)

closed cell is.

6. The method according to any one of claims 1 to 5, wherein first the foamed phase (G) is introduced into a mold, and then the non-foamed polymer phase (P) is poured into this mold.

7. The method according to any one of claims 1 to 6, wherein at least one of the monomers (M) is selected from the group comprising caprolactam, lauryl lactam and mixtures thereof.

8. The method according to any one of claims 1 to 7, wherein the anionic polymerization of the at least one monomer (M) in the presence of a catalyst (K) and / or an activator (A) is carried out.

9. Composite component, producible by the method of one of claims 1 to 8.

Use of a composite component, which can be produced by the method of one of claims 1 to 8, as a structural element in the automotive industry.