Compression-molding charging

Figure 8.8 Schematic diagram of the compression molding of a rectangular charge. Table 8.5 Example 8.4 Data...

Solution of the two-dimensional Poisson s equation compression molding. To illustrate the use of the four-noded isoparametric element, we can solve for the pressure distribution and velocity field during compression molding of an L-shaped polymer charge, shown in Fig. 9.18, with the physical and numerical data presented in Table 9.3. 

Write a boundary element program that will predict the pressure and velocity fields for the 1 cm thick L-shaped charge depicted in Fig. 10.42. Assume a Newtonian viscosity of 500 Pa-s. Note that for this compression molding problem the volume integral must be included in the analysis. 

Besides PMMA, compression molding was also used to fabricate microstructures on PC chips (1 mm thick). High temperature (188°C) and pressure (11 metric ton pressure applied by a hydraulic press) were used. Before bonding, the hydrophobic channel surface was treated with UV irradiation (220 nm) to increase surface charge, which would assist aqueous solution transport. The molded chip was thermally bonded to another PC wafer. During use, the bonded chip did not yield to a liquid pressure up to 150 psi (134°C, 4 metric ton, 10 min) [938],... 

BMC can be molded by compression-, transfer-, or injection molding processes. Compression molding is the oldest and most commonly used process. It consists of forming the material between the heated metal punch and die. This process is the most economic one however there are a few components that cannot be compression molded owing to their intricate shapes. Another drawback of compression molding process involves weighing of the charge before it is laid out... 

Fig. 37 Chemical structure of PEI (identical for Ultem 1000 and 7a) and isothermal surface potential decay (ITPD) curves of compression molded and corona charged films of Ultem 1000 and 7a [68], Published by permission of Wiley Periodicals Inc...

Fig. 38 Chemical structure of Irgafos P-EPQ top) and isothermal surface potential decay (ITPD, bottom) curves of melt compounded, compression molded, and corona charged films of PEIpur additivated with 5,000 (filled diamonds), 3,200 (filledpentagons), 2,200 (filled triangles), 1,200 (filled circles), 700 (filled inverted triangles), and Oppm (filled hexagons) Irgafos P-EPQ. For comparison, the curve for commercial Ultem 1000 films (open squares) is also included [68]. Published by permission of Wiley Periodicals Inc...

Figure 44 presents the TSC spectra of non-aged and aged compression molded and charged films of Ultem 1000. As mentioned before, amplitude and location of... 

Fig. 44 Thermally stimulated discharge (TSC) curves recorded at a heating rate of200 K/h of nonaged and aged compression-molded Ultem 1000 films. Films of 100 pm thickness were corona charged to +400 V for 20 s...

Fig. 45 Isothermal potential decay (ITPD) as a function of the time at Titpd of compression-molded and corona charged Ultem 1000 films, aged at rage = 200°C for tage = 4 days prior to corona charging...

Compression molded F-PEI films of 100 [tm thickness were utilized to investigate their charge storage characteristics. After corona charging to +400 V for 20 s, ITPD measurements at 90 °C were conducted. Figure 46 compares the remaining normalized surface potentials of all F-PEIs after 24 h at 90 °C. 

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