Birefringence distribution

Figure 7.2. Birefringence distribution along the diameter of an injection-molded polycarbonate disk. Reproduced with permission from reference 10. Copyright 1986 John Wiley and Sons.)...

Jansen, K.M.B. Flaman, A.A.M. Influence of surface heating on the birefringence distribution... 

Sharpless, G., CD and DVD disc manufacturing, on www.disctronics.com, 2003. Wimberger-Friedl, R., Analysis of the Birefringence Distributions in Compact Discs, Polym. Eng. ScL, 30, 813, 1990. 

Figure 8, The birefringence distribution of the injection-molded polymers.

Polymer structure n. (1) A general term referring to the relative positions, arrangements in space, freedom of motion of atoms in a polymer molecule, and orientation of chains. Such structural details have important effects on polymer properties such as the second-order-transition temperature, flexibility, and tensile strength. (2) The microstructure of a polymer, as observed by light- or electro-microscopic techniques, and including crystalline structure, birefringence, distribution of sizes of filler particles and spherulites, and distribution of reinforcement directions. These, too, have important influences on macroscopic properties and behavior. 

Figure 14.15(a) depicts the induced birefringence distribution of a 10 pm thick IPS-5/5 cell and Figure 14.15(b) shows the VT curves of the IPS-5/5 cell with different cell gaps. The material employed here is JC-BPOl. From Figure 14.15(a), the induced birefringence is largest near... 

Figure 4. Birefringence distribution over the thickness of an injection moulded CD substrate at r = 35 mm (8).

Figure 7 (a) A side view, (b) sliced side view, of the birefringence distributions of the convex lens model. 

BIREFRINGENCE DISTRIBUTION IN GAS-ASSISTED TUBULAR INJECTION MOLDINGS SIMULATION AND EXPERIMENT... 

Figure 3. Measured (symbols) and predicted (lines) birefringence distribution of An and nee-n at various distances from the sprue entrance (a) sprue region at 4 cm, (b) sprue region at 6.5 cm, (c) spiral region at 11 cm, (d) spiral region at 16 cm, and (e) in the solid region at 28 cm. Condition 1.

Melt temperature has significant influence on residual birefringence distribution. Figure 3 shows the gapwise averaged birefringence distribution under different melt temperature. As the melt temperature increases, relaxation time of flow stresses beeomes shorter, so reduce the final molecular orientation. When melt temperature decreases. 

There has apparent anisotropy at the hot weldline area as can be seen from the fringe pattern, which is influenced by molecular orientation at fountain flow and complex flow behavior behind the obstacle. Geometry of obstacles and weldline meeting angle also has influence on the gapwise birefringence distribution. 

BIREFRINGENCE DISTRIBUTION IN INJECTION MOLDED PARTS WITH WELD LINES. ... 

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