Polyurethane, object fabrication

In contrast to the pieces used in 2D MESA, the pieces used in 3D MESA were made of polyurethane rather than PDMS. Objects made of PDMS aggregate in water, regardless of whether they are coated with liquid or not because it is compliant, contacting surfaces come into intimate contact it is also hydrophobic. The choice of polymer arose from purely practical considerations fabrication... 

Polyurethanes (PUs) are found everywhere the chair we sit on, the comfortable bed we sleep on, every nook and comer of our house, the car we drive, the refrigerator and air conditioner that comfort us, and many other day-to-day objects. PUs can also be used for dmg delivery and may be fabricated as bioinert, biodegradable, stimulus-responsive, shape-memory, conjugated, self-assembled, rigid, flexible, and porous systems. 

This objective is being achieved by the use of many different materials and processes. As ever with plastics, the main theme is consolidation of components. For interior panels, this takes the form of integrating two or more layers in a sandwich construction. Examples include a textile skin formed over wood-filled polypropylene pressing, in a single operation, to produce a door panel, and a unit seat, in which the polyurethane foam is formed with the fabric facing already in position. 

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