Moulded product for automotive panels
Composite moulded product comprising of at least one polyamide-reinforcement layer consisting of a polyamide matrix and reinforcement fibers, characterised in that the polyamide-reinforcement layer is porous due to the consolidation using a pressurised steam process.
1. A composite moulded product, comprising:
at least one polyamide-reinforcement layer including a polyamide matrix and a plurality of reinforcement fibers, wherein a polyamide matrix material that forms the polyamide matrix before consolidation, includes at least one of fibers, powder, or flakes,
wherein the polyamide matrix and the plurality of reinforcement fibers have been consolidated as a result of pressurized steam such that the at least one polyamide-reinforcement layer is porous.
2. The moulded product according to claim 1 , wherein the plurality of reinforcement fibers are chosen such that a dynamic young modulus of the polyamide-reinforcement layer does not change more than 20% over a temperature range of 150° C. to 210° C.
3. The moulded product according to claim 1 , wherein a density of the moulded product is from 5% to 80% of a bulk density of the polyamide matrix and the plurality of reinforcement fibers.
4. The moulded product according to claim 1 , wherein a tensile loss factor of the moulded product is less than 0.15 over a temperature range of 60° C. to 210° C.
5. The product according to claim 1 , wherein the polyamide matrix includes at least one of polyamide-6, polyamide-6.6, and a mixture of different types of polyamide.
6. The moulded product according to claim 1 , wherein the plurality of reinforcement fibers include at least one of mineral fibers, glass fibers, carbon fibers, and basalt fibers.
7. A method of producing a porous moulded product, comprising:
randomly disposing polyamide-binding material, and a plurality of reinforcement fibers to form a web, the polyamide-binding material including at least one of fibers, flakes, and powder: and
treating the web with pressurized steam to consolidate the web.
8. The method according to claim 7 , wherein saturated steam having a pressure in a range of 9 to 20 bars is used.
9. The method according to claim 7 , wherein the web is treated in a pressure resistant mould having at least one steam permeable surface forming the moulded product.
10. The method according to claim 7 , wherein the web is prebonded before steam treatment.
11. The moulded product according to claim 1 , wherein the plurality of reinforcement fibers include thermoplastic polymer fibers having a melting temperature measured according to a Differential Scanning Calorimetry standard which is higher than a melting temperature of the polyamide matrix under steam pressure.