| 摘要 |
<p>1337729 Polyamide foams BAYER AG 23 Dec 1970 [24 Dec 1969] 61026/70 Heading C3C [Also in Division B5] In a process for the continuous production of polyamide foam sections by the ionic polymerization of lactams, a polymerizable, foamable lactam mixture is delivered from a mixing head 2 into the lower half of a stationary mould 4, and, after the formation of a firm foam in the mould, the foam 6 is drawn off vertically upwardly by a take-off mechanism in the form of a continuously revolving belt 8, deflected, and subjected to a final moulding treatment by suitably profiled rollers 9. Optionally the product is passed through an "after treatment'' zone 10 where the monomer adhering to the surface of the foam is reduced by steam treatment or annealing. Reinforcing foils of aluminium or polyester resin may be provided on the outer surfaces of the foam section. The mould, which is of steel, non-ferrous metals, glass, ceramics, wood, or plastics is provided with heating and cooling means, and is coated with a release agent. In an alternative embodiment, the take off mechanism may be incorporated in the profiling rollers. In an example, a mixture of #-caprolactam, hexamethylene-1,6-diisocyanate (activator and expanding agent) silicone stabilizer, finely divided silicate, and sodium borohydride (catalyst) is used as the melt.</p> |
