| 摘要 |
The present invention relates to a process and a device for producing sheets, webs, sheet-like mouldings or profiles from plastics, preferably thermoplastics, of high mechanical strength as a result of a molecular orientation due to roll-press stretching within the roll nip of at least one pressure or compression roll pair at roll temperatures and material temperatures below the crystallite melting point or the softening point of the plastic and above 303 K, with compression stretching, the roll-press stretching of the sheets, webs, sheet-like mouldings or profiles being carried out with the same or approximately the same circumferential velocity of the pressure or compression rolls or without friction at pressures of 20 to 250 MPa, preferably 25 to 150 MPa, at a degree of pressure-stretching of above 1.1, preferably 2.1. The device consists of one or more pressure rolls, at least one of which is supported in vertically adjustable, depth-adjustable and/or laterally adjustable bearing elements, devices for regulatable temperature control, preferably heating of the roll surface and devices, in conjunction with the bearing elements of the adjustable roll, to receive a linear load in the roll nip of 950 N/mm to 5,500 N/mm.
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