| 摘要 |
Polyamide membranes of desired thickness are prepared by dissolving polyamide in HCl, admixing paraformaldehyde and then zinc chloride to produce a viscous paste, forming expanded gelatinous material by treatment with formaldehyde, curing this material and applying tensile stress thereto. Rigid, water insoluble, polyamide foam material is prepared by treating polyamide with concentrated solution of zinc chloride in HCl to make a gum-like solid and supernatant liquid, admixing 1,3,5-trioxane and the gum-like solid to make a homogeneous, light, and flowable paste which is then cured in a suitable mold at atmospheric conditions, preferably in the presence of weakly acidic water. The membranes are useful, e.g., for bandages and the nylon foam is useful, e.g., as a construction material, for trays, containers, etc.
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