Abstract:
PROCESS AND APPARTUS FOR PREPARING A CATALYST FOR THE ANIONIC POLYMERIZATION OF LACTAMS, IN WHICH A LACTAM AND A ALKALI METAL HYDROXIDE ARE CONTINOUSLY FED INTO A FIRST REACTION VESSEL THE LIQUID LEVEL IN SAID VESSEL BEING KEPT CONSTANT BY FEEDING A PORTION OF THE REACTION MIXTURE INTO A SECOND VESSEL AND THE LIQUID LEVEL IN SAID SECOND VESSEL BEING KEPT CONSTANT BY DISCHARGINGG A CONTINUOUS STREAM OF THE REACTION MIXTURE FROM SAID VESSEL. THE WATER FORMED IN THE REACTION VESSELS IS EVAPORATED BY HEATING IN VACUO AND THE VAPOUR THUS FORMED IS PASSED THROUGH A CONDENSER IN WHICH THE LACTAM IS CONDENSED AND RETURNED TO THE REACTION VESSELS.
Abstract:
THE USE OF CARBOXYLIC ESTERS OF KETOXIMES, IN WHICH AN ACYL RADICAL HAS BEEN SUBSTITUTED IN THE MOLECULE FOR ONE OF THE HYDROCARBON RADICALS OF THE KETOXIME, AS PROMOTERS, USED IN CONJUNCTION WITH CATALYSTS, IN THE IONIC POLYMERIZATION OF LACTAME, IS DISCLOSED. THE USE OF SUCH PROMOTERS PERMITS RAPID POLYMERIZATION WITH HIGH YIELDS OF AMIDE POLYMERS, WHICH ARE USEFUL IN THE PRODUCTION OF MOLDED PRODUCTS.
Abstract:
1,147,160. Moulded anionic lactam polymers. STAMICARBON N.V. 28 Oct., 1966 [3 Nov., 1965], No. 48530/66. Heading B5A. [Also in Division C3] A lactam is anionically polymerized at 175 to 210‹ C. using a catalyst but no promoter to obtain a liquid polymer which remains liquid when cooled to 140 to 170‹ C. and a promoter is then mixed with the cooled liquid polymer and the mixture is poured into a mould heated at 140‹ to 170‹ C. wherein it is further polymerized to a solid polymer. Various catalysts and promoters are mentioned. It is stated that the moulds may be made of material with which the monomer-catalyst mixture would be too reactive e.g. epoxy resins. Fillers or dyes may be mixed with the liquid polymer before moulding. In the examples caprolactam is polymerized using KOH as catalyst and dicaprolactam ether as promoter (1) in a cylindrical glass mould and (2) a two part disc-shaped brass mould.