摘要 |
A shear-fusion bond method is provided to create a direct fusion joinder or bond over an extended interface between like thermoplastic elastomeric elements of a block copolymer having a rubber-like center or mid-block and styrene end blocks. Such material has a high melt viscosity and does not readily flow. The interface surfaces are coupled to a heat source and heated to a fusion bonding temperature, thereby softening the interface material so that it flows under pressure. The elements, with the surfaces in pressurized engagement, are rotated relative to each other about an axis which is normal to the interface. Rotation is through an angle of at least 10 degrees to subject the softened interface material to a high rate shear force movement substantially in the plane of the interface. This decreases the viscosity and causes the interface material to bondably flow. The interface surfaces are firmly held together while in the bondably flowing state to create a shear-fusion bond in which the interface disappears. The surfaces may be separately heated on a hot platen and then located in abutting engagement for rotation. The surfaces may also be provided with appropriate heat generating particles. The surfaces are inductively heated from a suitable field source to soften the interface, and then rotated. |