DEVICE FOR PRODUCTION OF EXTRA PURE POLYMER FOR POLYMERIC OPTICAL FIBRE Russian patent published in 2001 - IPC

FIELD: processing of extra pure polymeric materials, in particular, device for moulding of nucleus and reflecting shell of polymeric optical fibre. SUBSTANCE: extra pure polymer for polymeric optical fibre is produced with the aid of a screw extruder with a vacuum zone. The extruder has a body, screw and a chamber positioned between the charging opening and the gland. The chamber accommodates two hollow cylinders aligned one in the other. The external cylinder has a screw thread on the inner and outer surfaces, and with one side it is hermetically attached to the screw. The internal cylinder, in which the gland is coaxially positioned, is hermetically connected to the extruder body. Besides, the external cylinder has the configuration of the screw thread on the outer surface facilitating the movement of mechanical particles and traces of lubricant from the gland in the direction opposite the direction of movement of the main mass of the polymer melt. The internal hollow cylinder on the inner surface has a number of concentric bosses, several millimeters high. EFFECT: prevented getting of mechanical impurities from the extruder gland to the polymeric melt in production of polymeric optical fibre. 3 cl, 2 dwg