ADHESION OF BLOWING AGENT-CONTAINING PARTICLES BASED ON POLYIMIDES OR POLYACRYLATES

Abstract

A process for the production of functionalized particle foam mouldings based on a thermoplastic base material with a glass transition temperature of at least 100 C. involves functionalization of base particles.

Claims

1: A process for production of a functionalized particle foam moulding based on thermoplastic base material with a glass transition temperature of at least 100 C. measured by DSC according to DIN EN ISO 11357-2, published: 2014-07, the process comprising in the sequence specified: a) providing base particles comprising at least one blowing agent and at least one nucleating agent; b) feeding the base particles into a device suitable for moving and heating the base particles; c) simultaneously pre-foaming and functionalizing the base particles, by bringing the base particles into contact with a solution or dispersion comprising at least one functionalizing agent, wherein the at least one functionalizing agent is an adhesive and, optionally, one or more further functionalizing agents are used together with the adhesive to functionalize the base particles, and wherein the base particles are treated with a solution or emulsion of water and/or solvent and the at least one functionalizing agent, so that functionalized particles are obtained which have at least partially an adhesive layer and, optionally, one or more functionalizations on their surface; d) optionally, drying the functionalized particles; e) optionally, interim storing of the functionalized particles; and f) mould foaming of the functionalized particles by heating in a shaping container so that a functionalized particle foam moulding is formed.

2: The process according to claim 1, wherein the base material is selected from the group consisting of polyimide, polyacrylate, and mixtures thereof.

3: The process according to claim 1, wherein the at least one blowing agent is selected from the group consisting of volatile organic compounds having a boiling point at standard pressure below a glass transition temperature of the base material, inorganic blowing agents, thermally decomposable blowing agents, and mixtures thereof.

4: The process according to claim 1, wherein the at least one functionalizing agent is selected from the group consisting of biocides, fungicides, adhesives, fibers, dyes, pigments, electrically conductive base particles, and mixtures thereof.

5: A method for production of a part for the aerospace industry, for shipbuilding, for wind power, sport and leisure equipment, or for vehicle construction, the method comprising: forming the part with the functionalized particle foam moulding produced by the process according to claim 1.

6: The process according to claim 2, wherein the base material is selected from the group consisting of polymethacrylimide (PMI), polyetherimide (PET), polymethyl (meth)acrylate (PM(M)A), and mixtures thereof.

7: The method according to claim 5, wherein the part is an electrical mobility vehicle part.

Description

EXAMPLES

Example 1

[0124] base polymer: polyetherimide (type: ULTEM 1000, manufacturer: SABIC) [0125] nucleating agent: talc (type Luzenac, manufacturer: IMERYS) [0126] blowing agent: acetone [0127] functionalization: biocides (e. g. silver) [0128] pre-foaming furnace: rotary furnace with IR-radiation field (type: IRD90/100, manufacturer: Kreyenborg GmbH) [0129] reaction speed: 30 min.sup.1 [0130] pre-heating: 90 C. for 15 minutes [0131] pre-foaming: 155 C. for 5 minutes [0132] additive metering reactive solution: 0.1 l/min for 2 minutes [0133] bulk density base particles: 740 kg/m.sup.3 [0134] bulk density functionalized particles: 90 kg/m.sup.3

[0135] After melting polyetherimide (type: ULTEM 1000, manufacturer: SABIC) in an extruder, the nucleating agent talc (type Luzenac, manufacturer: IMERYS) is added and on cooling the base material, the blowing agent acetone. The base particles can then be formed mechanically, by using a perforated plate.

[0136] The base particles are fed to a heatable, rotatable oven (rotary furnace with IR-radiation field (type: IRD90/100, manufacturer: Kreyenborg GmbH)) and in process step c) are sprayed with a dispersion comprising the functionalizing agent silver (biocides) while the drum is heated and rotated, whereby the base particles are moved against each other during the pre-foaming and functionalization. This preferred embodiment a particularly homogeneous functionalization of the base particles.

Example 2

[0137] base polymer: polymethacrylimide (type ROHACELL Triple F, manufacturer: Evonik) [0138] glass transition temperature: 217 C. (measured by DSC according to DIN EN ISO 11357-2 [0139] (publication date: 2014-07), [0140] nucleating agent: SiO.sub.2 [0141] blowing agent: urea [0142] functionalization: adhesive (type Dynacoll, manufacturer: Evonik) [0143] pre-foaming furnace: continuous furnace with IR-radiation field (manufacturer: Fill GmbH) [0144] conveyor speed: 0.5 m/min [0145] pre-heating: - [0146] pre-foaming: 210 C. continuous [0147] additive metering reactive solution: 0.1 l/min continuous [0148] bulk density base particles: 600 kg/m.sup.3 [0149] bulk density functionalized particles: 140 kg/m.sup.3

[0150] After melting polymethacrylimide (type ROHACELL Triple F, manufacturer: Evonik) in an extruder, the nucleating agent SiO.sub.2 is added and on cooling the base material, the blowing agent urea. The base particles can then be formed mechanically, by using a perforated plate.

[0151] The base particles are fed to a heatable, rotatable oven (continuous furnace with IR-radiation field (manufacturer: Fill GmbH)) and in process step c) are sprayed with a dispersion comprising the functionalizing agent adhesive (type Dynacoll, manufacturer: Evonik) while the drum is heated and rotated, whereby the base particles are moved against each other during the pre-foaming and functionalization. This preferred embodiment a particularly homogeneous functionalization of the base particles.