Plasticator deep-channel

Moreover, a Zeonor plastic plate, normally used to manufacture CDs and DVDs, was hot-embossed (130°C, 250 psi) using a Si master. The embossed chip (with microchannels 60 im wide and 20 pm deep) was thermally bonded to another Zeonor plate (85°C, 200 psi, 10-15 min) [808], In another report, a 2-mm-thick cyclo-olefin (Zeonor 1020 R) substrate was embossed using a Si master to create 20-pm-wide and 10-pm-deep channels [788],... 

The screw has three zones—the feed, compression (or transition), and metering. The feed zone picks up the material from the hopper and feeds it at a pressure sufficient to assure proper functioning of the compression zone. Feed zone conveying is optimized by a deep screw channel and a helix angle appropriate for the coefficient of friction between the polymer and screw. A helix angle of 17.7 deg has been used for many plastics. The channel depth of the feed zone may be approximately three times that of the metering zone. ... 

FIGURE 8.33 Degassing in a single-screw extruder. Zone 1 consists of a typical plasticating screw section zone 2 is a deep channel section with a vacuum port zone 3 is a metering section. The channels in zone 2 are partially full to facilitate degassing. 

Figure 15.21 Photograph of a TS cooling screw model segment showing the multiple, deep flights and the circulation channels positioned in the flights (courtesy of James D. Fogarty of Plastic Engineering Associates Licensing, Inc.)...

Figure 7 is a photograph of the 2300-sq.-foot air-supported plastic still. This still consists of rows of separate channels, each provided with a waterproof plastic basin and an air-supported transparent plastic cover. The design incorporates a relatively shallow basin, containing only a few inches of water, so that there is much less thermal inertia than in the deep-basin still. 

Ablation using radiations of various wavelengths (IR, visible, UV, or x-ray) has been employed to fabricate plastic chips. For instance, photoablation using pulsed UV lasers (193 nm) has been used to fabricate plastic chips out of polyethylene terephthalate (PET, 100 pm thick) [189,190, 258,758] and polycarbonate (PC, 125 pm thick) [189,258]. Channels as narrow as 30 pm and as deep as 100 pm can be made [258,758]. The cross section of a photoablated PET channel plate laminated with another PET using a thin PE adhesive layer was shown in Figure 2.20 [191]. 

The technique of isoelectric focusing has proven to be a useful tool in protein chemistry, and this too has been adapted to the microchip. Using 7-cm-long channels in glass microchips (200 [Xm wide and 10p,m deep) mixtures of Cy5-labeled peptides can be focused in less than 30 seconds. This same procedure has also been applied to plastic microchips made from EMMA by laser ablation and shown to focus mixtures of peptides labeled with rhodaraine green. Results for this type of microchannel isoelectric focusing are available in less than 5 minutes compared with traditional techniques that take over 1 hour. 

Design of the individual separation disk for four separate spiral channels is shown in Fig. 2b. A plastic disk (17.5 cm diameter and 4 mm thick, high-density polyethylene) has four spiral channels (grooves), each 2.6 mm wide, 2 mm deep, and 1 m long, with a capacity of about 6 ml. The ridge between each groove is 1 mm and, therefore, the pitch of each spiral becomes as large as 16 mm (four times that of... 

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