A process for the production of hollow articles from anionic polymerisable lactams

1,133,840. Hollow articles from polymerized lactams. FARBENFABRIKEN BAYER A.G. 30 May, 1967 [7 June, 1966], No. 24847/67. Heading B5A. Hollow articles are produced from anionic polymerizable lactams by introducing into a hollow mould an anhydrous melt containing (a) a lactam with 4 to 12 ring atoms or a mixture of such lactams, (b) a catalyst which is an alkali metal, an alkali metal salt of a lactam or an alkali metal or alkaline earth metal alcoholate, hydroxide or carbonate and (c) an activator which is an organic isocyanate, a masked isocyanate, a carbodiimide or a cyanamide, rotating the mould about two mutually perpendicular axes and heating the mould to 80-210‹ C. The mould is preferably rotated at 2 to 50 r.p.m. about each axis. The lactam may be #-caprolactam, pyrrolidone, caprylic lactam, oenanthic lactam or lauric lactam, the catalyst sodium or potassium carbonate or sodium methoxide and the activator hexamethylene diisocyanate, toluylene-2,4-diisocyanate, napthalene-1,5-diisocyanate, the addition products of hexamethylene diisocyanate and #-caprolactam or of toluylene diisocyanate and #-caprolactam, diethylcarbodiimide or polycarbodiimide. Glass fibres, pigments, dyes, stabilizers and fillers may also be added to the melt.