Abstract: A method for manufacturing a sheet molded part by polymerization of lactams in a sheet mold includes the steps of placing a fiber composite material into a sheet mold having large plane surfaces and fixedly positioning the fiber composite material in the sheet mold. Subsequently, the lactams are introduced into the sheet mold and the lactams are polymerized.

Abstract: A pultrusion processing method for long fiber-reinforced nylon which combines the nylon anionic ring-opening polymerization technology and the pultrusion processing method to manufacture long fiber-reinforced thermoplastic nylon composites. The method comprises the steps of forming an active caprolactam sodium salt catalyst composition by reacting melt nylon 6 monomer raw material, i.e., caprolactum, with sodium hydride, forming co-catalyst composition by melting caprolactam and a polymeric co-catalyst, then mixing the active caprolactum sodium salt catalyst composition and the co-catalyst composition in a continuous mixing device to obtain a reaction mixture with low viscosity. The mixture is then charged into a closed impregnating tank to impregnate preheated and dried reinforced fiber, which is immediately pulled into a hot mold for composite molding processing to form a finished product of long fiber-reinforced nylon composites.

Abstract: A process for producing large-size formed articles consisting of a modified polyamide, by polymerization of a mixture containing, besides the omega-lactam corresponding to the polyamide, the following reagents:a) a polymerization catalyst selected from the sodium salt and the potassium salt of said omega-lactam;b) a polyoxyalkylene polyamine having a molecular weight ranging from 400 to 5,000 and an amine functionality ranging from 1.9 to 2.5;c) an activator consisting of a polyisocyanate having all the isocyanic groups blocked with a lactam;said reagents being fed, at a temperature of from 105.degree. to 125.degree. C., to a mold heated to 130.degree.-170.degree. C.

Abstract: A method for producing a sliding coupling, w hich comprises injecting a casting material comprising the following components (A) and (B) into a clearance between a bearing and a shaft fitted in and rotatably or reciprocatively supported by the bearing, wherein a primer is preliminarily applied to either the shaft or the bearing and a releasing agent is preliminarily applied to the other; followed by polymerization and curing to form a resin lining on the surface of the shaft or the bearing:(A) a .OMEGA.-lactam liquid containing a polymerization catalyst of an alkali metal or alkaline earth metal compound; and(B) a .OMEGA.-lactam liquid containing at least one polymerization initiator.

Abstract: The present invention relates to masterbatches in the form of granules or pellets, as well as the process for obtaining these.These granules or pellets consist of:At least 37.5% of polycondensates serving as a carrier, of which at least a part consists of the same polycondensate as that which is to be shaped, in the form of a powder of particle size at least 50 microns,From 12.5 to 40% of a binder of melting point 70.degree. - 100.degree. C which is compatible with the polycondensate to be shaped, andUp to 50% of at least one compound intended to modify the polycondensate to be shaped.They are used with advantage for modifying polycondensates, particularly polyamides and polyesters, intended for spinning or moulding.