Thermoplastic compositions for producing metallic moldings

Claim 2

A thermoplastic composition for producing a metallic molding, containing A) 40-65% by volume of a sinterable pulverulent metal or of a pulverulent metal alloy or of a mixture thereof, B) 35-60% by volume of a mixture of B1) 85-95% by weight of a polyoxymethylene homopolymer or copolymer and B2) 4-15% by weight of a polymer homogeneously dissolved in B1) or dispersed therein with an average particle size of less than1 μm, as binder, and C) 0-5% by volume of a dispersant, wherein component B2) is an aliphatic uncrosslinked polyepoxide, an aliphatic polyamide or polyacrylate or a mixture thereof.

Claim 3

A metallic molding produced from a thermoplastic composition as claimed in claim 1.

Claim 4

A thermoplastic composition according to claim 1, wherein component B2) is an aliphatic uncrosslinked polyepoxide.

Claim 5

A thermoplastic composition according to claim 1, wherein component B2) is an aliphatic polyamide.

Claim 6

A thermoplastic composition according to claim 1, wherein component B2) is a polyacrylate.

Claim 7

A metallic molding produced from a thermoplastic composition as claimed in claim 3.

Claim 8

A metallic molding produced from a thermoplastic composition as claimed in claim 4.

Claim 9

A metallic molding produced from a thermoplastic composition as claimed in claim 5.

Claim 10

A process for preparing a thermoplastic composition containing as essential components A) 40-65% by volume of a sinterable pulverulent metal or of a pulverulent metal alloy or of a mixture thereof, B) 35-60% by volume of a mixture of B1) 85-95% by weight of a polyoxymethylene homopolymer or copolymer and B2) 5-15% by weight of a polymer homogeneously dissolved in B1) or dispersed therein with an average particle size of less than 1 μm, as binder, and C) 0-5% by volume of a dispersant, wherein component B2) is an aliphatic uncrosslinked polyepoxide, an aliphatic polyamide or polyacrylate or a mixture thereof which comprises a) melting component B) at 150°-220° C. and then b) metering component A) into the melt stream of component B) with or without C) at a temperature within the same range as in step a).

Claim 11

A process for preparing a thermoplastic composition containing as essential components A) 40-65% by volume of a sinterable pulverulent metal or of a pulverulent metal alloy or of a mixture thereof, B) 35-60% by volume of a mixture of B1) 85-95% by weight of a polyoxymethylene homopolymer or copolymer and B2) 5-15% by weight of a polymer homogeneously dissolved in B1) or dispersed therein with an average particle size of less than 1 μm, as binder, and C) 0-5% by volume of a dispersant, wherein component B2) is an aliphatic uncrosslinked polyepoxide, an aliphatic polyamide or polyacrylate or a mixture thereof which comprises a) melting component B) at 150°-220° C. and then b) metering component A) into the melt stream of component B) with or without C) at a temperature within the same range as in step a).

Claim 12

A process for removing the binder from a preform produced from a thermoplastic composition as claimed in claim 1, which comprises a) producing a preform from the thermoplastic composition by injection or extrusion molding, b) treating the resulting preform at from 20° to 180° C. with a gaseous acid-containing atmosphere for 0.1-24 h, and c) then heating it at 250°-500° C. for 0.1-12 h.

Claim 13

A process for preparing a thermoplastic composition according to claim 9, wherein component B2) is an aliphatic uncrosslinked polyepoxide.

Claim 14

A process for preparing a thermoplastic composition according to claim 9, wherein component B2) is an aliphatic polyamide.

Claim 15

A process for preparing a thermoplastic composition according to claim 9, component B2) is a polyacrylate.

Claim 16

A process for removing the binder from a preform produced from a thermoplastic composition as claimed in claim 3, which comprises a) producing a preform from the thermoplastic composition by injection or extrusion molding, b) treating the resulting preform at from 20° to 180° C. with a gaseous acid-containing atmosphere for 0.1-24 h, and c) then heating it at 250°-500° C. for 0.1-12 h.

Claim 17

A process for removing the binder from a preform produced from a thermoplastic composition as claimed in claim 4, which comprises a) producing a preform from the thermoplastic composition by injection or extrusion molding, b) treating the resulting preform at from 20° to 180° C. with a gaseous acid-containing atmosphere for 0.1-24 h, and c) then heating it at 250°-500° C. for 0.1-12 h.

Claim 18

A process for removing the binder from a preform produced from a thermoplastic composition as claimed in claim 5, which comprises a) producing a preform from the thermoplastic composition by injection or extrusion molding, b) treating the resulting preform at from 20° to 180° C. with a gaseous acid-containing atmosphere for 0.1-24 h, and c) then heating it at 250°-500° C. for 0.1-12 h.