Process for the production of polyamide castings
Abstract
Abstract A PROCESS FOR THE PRODUCTION OF POLYAMIDE CASTINGS, CONTAINING CAVITIES OR FITTED WITH A METAL SHAFT, BY AN ACIVATED ANIONIC POLYMERIZATION OF LACTAMS IN A MOULD, THE MOULD BEING FITTED WITH A COMPOSITE CORE OR METAL SHAFT, THE CORE OR METAL SHAFT HAVING AN OUTER INFLATABLE JACKET PREPARED BY WINDING AN ELASTIC TUBE AROUND THE INNER CORE OR METAL SHAFT WITH NEIGHBORING TURNS IN ENGAGEMENT, INSERTING THE COMPOSITE CORE OR METAL SHAFT INTO A PREHEATED STATIONARY MOULD, INFLATING THE TUBE WITH COMPRESSED GAS, FILLING THE MOULD WITH A LACTAM MELT CONTAINING AN ALKALINE CATALYST, PROMOTER, AND/OR PIGMENTS, AND/OR FILLERS, AND/OR OTHER ADDITIVES, THE LACTAM MELT THEN BEING POLYMERIZED AT A TEMPERATURE LOWER THAN THE MELTING POINT OF THE POLYLACTAM FORMED, AND AFTER COOLING, THE COMPOSITE CORE INCLUDING SAID OUTER INFLATABLE JACKET IS REMOVED FROM THE FINISHED CASTING TO GIVE A CASTING WITH A CAVITY OR IN WHICH THE METAL SHAFT TOGETHER WITH THE OUTE INFLATABLE JACKET REMAINS TIGHTLY GRIPPED IN THE CASTING.
Inventors
- 👤 Jan Drabek
- 👤 Oto Horak
- 👤 Zdenek Ditrych
- 👤 Syatoslav Zahorovsky
Bibliographic Details
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