| 摘要 |
Lamination of polymethacrylate plastics (I) by thermal bonding of at least 2 surface-heated layers comprises passing the layers (1), which are preheated to surface temps. of 130-200 degrees C on the side (1a) to be bonded, whilst retaining their original shape, between a pair of rollers (2,3), at least one (3) of which exerts pressure (4), at a rate of 5-200 mm/s and pressure of 10-500 N. Pref. the difference between the surface temp. and core temp. of the layer is at least 20, esp. at least 50 K. Flat or elongated inserts may be incorporated, which have thicknesses of up to 50, esp. up to 25% of the thickness of the (I) layers and cover at most 90% of the bonding area. Alternatively, the bonding surface may be engraved or imprinted to a depth of at least 0.2, esp. at least 1 mm so that the laminate has 3D inclusions of definite shape. The layers (1) are sheets or films and are 0.5-100, esp. 1-50 mm thick, 0.1-2 m wide and 0.1-5 m long. The polymer contains at least 50, esp. at least 80 wt.% methyl methacrylate (MMA) units. The flat inserts consist of thermoplastic elastomers; and the elongated inserts are wires, steel coils or filaments, esp. plastics filaments with high elasticity and high modulus. |
