GB780122A - Improvements in or relating to the molecular ordering of materials comprising high polymers - Google Patents

Abstract

780,122. Plasticizing rubber: making rings &c. from synthetic resins &c. DUFOUR, P. F. J. May 13, 1953, No. 13358/53. Classes 70 and 87(2). A process of molecular ordering for creating, developing, orienting and balancing at least one three-dimensional system of orderly and regulated molecular alignments in the microstructure of a material which comprises at least one high-polymer in its plastic phase, comprises simultaneously compressing, rolling and bending the material without subjecting it to shearing effects by feeding one or more portions of the material into a space which is partly or wholly annular in cross-section and is defined by two surfaces which are of part-tubular or tubular shape, the two surfaces undergoing relative movement in their length direction, whereby the one or more portions is or are compressed, flattened and bent transversely of the length direction of the part-tubular or tubular surfaces, and is or are caused to assume a homogeneous body in which the high polymer is molecularly ordered. The part-tubular or tubular surfaces may undergo continuous or intermittent relative motion in order to modify the ordering and regulation of the system of molecular alignments. In the case of treating a material having thermosetting characteristics, sufficient heat is supplied to maintain it in its plastic state during processing and then to cause thermosetting after establishment of the three-dimensional system of molecular alignments. Gas producers may be introduced into the mix to produce gas inclusions in the product which may be a toroidal rubber ring, and by controlling the rolling the ring may be formed with a hollow annular space. In a preferred example the polymeric material is fed into a multi-calendering gap 3, Fig. 1, between two surfaces 1 and 2 by means of a guide ramp 7. Surface 2 is supported on a shaft 9 which can revolve freely in ball socket bearings 10 and 10a housed respectively in boxes 11 and 11a. Shaft 9 is converted by a universal joint 12 to the piston of a hydraulic cylinder 13 which can transmit a longitudinal motion of controllable amplitude. Boxes 11 and 11a are connected to the frame 14 by a device 15 which enables the axis of the surface 2 to be set eccentrically. Rotation of the bearings is effected by a motor 16 incorporating speed control 17. The processed helicoidal ring is diverted from the surface 2 by extending (by means of cylinder 13) the longitudinal path of the surface, the ring then drops to the lower part of the machine where shears 20 cuts it radially to facilitate its exit. In another example, a mandrel 26, Fig. 4, undergoes an alternating motion in the direction of the axis XX inside a tubular stationary casing 25. The multicalendering gap 3 increases from the ingress 29 to the egress 30. Transversely to the surface 32 is situated a rough cylindrical blank 34a in a feeder (not shown) the blanks being fed in pairs, one from each side of the mandrel. They are immediately gripped by coiler 35 and fed onto surface 2. The path of surface 2 is so selected that its eccentricity b is such that at the top, ring 5a leaves in the direction of the axis XX sufficient free space for the insertion and multicalendering of a fresh blank, thus allowing the multicalendering of several rings simultaneously.