Board-shaped polymer

Note 2 A polymer LC consisting of macromolecules of board-lrke shape can be called a board-shaped polymer LC. Such polymers can form sanidic mesophases. 

Polymer chain composed of a rigid backbone to which many lateral side-groups are attached, giving the repeating unit a board-like shape. 

Shrinkage happens when a plastic-based board, extruded and pulled from the die, cool too fast. Too fast means that stretched long polymer molecules, coming from the die, do not get enough time to settle, to come back to their thermodynamically favorable coiled form. They are trapped in the board solidihed matrix in an unsettled, stretched shape. 

Once such frozen boards are installed on a deck, and as soon as the sun is up and boards are heated, polymer molecules start to move, steadily reaching their thermodynamically settled, favorable final bean shape. The board becomes shorter compared to its preceding, frozen state. 

The blowing agent is usually chemically stable, volatile, and so its introduction into the molten polymer reduces the foam product density, by forming a myriad of closed cells. The foam is then trimmed to desired shape. The Foam Boards are packed into shrink-wrapped bundles on the pallets. And then these pallets are stored for curing during a certain period, until shipment. ... 

Conductive Columns. Nitto Denko Corp. developed an ACF for fine pitch flip chip applications (27). The features of this ACF were (1) connectability between bumpless chips and fine pitch PCB (2) high electrical conductivity (3) repairabil-ity (easy to peal off chips from a printed circuit board at elevated temperatures) (4) high reliability and (5) potential storage at room temperature. There are other notable features too (7) ACF is usable at pitches down to 25 fim, (2) the conductive elements are micrometallic columns as opposed to random-shaped particles, and (3) this adhesive matrix consists of a thermoplastic polymer resin, conductive columns coated with an insulator, and a high Tg polymer, which completely separates the columns from the adhesive (Fig. 6). 

Carbon fibers in felted or woven form are the preferred materials for high-temperature insulation forfurnaces operating above 1500°C in vacuum or inert atmosphere. However, these materials have a tendency to sag and compact with time which eventually results in non-uniform insulation characteristics. This problem is partially solved by the use of rigid insulation which consists of a felt impregnated with a polymer, subsequently pyro-lyzed, and fired and outgassed at 2000°C under vacuum. The material is available in the form of cylinders, boards, disks and specieil shapes to suit furnace demands. ... 

Fairly rigid main chain liquid crystalline polymers with disc-shaped units in the chain have been reported to form a sanidic (board-like) nematic phase, with a parallel alignment of the boards [367]. 

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