Core-shell separation die design

Polymer fibers prepared by the extrusion process without a core-shell separation die design. 

Gradient-index polymer fibers with a quadratic distribution of the refractive index were successfully prepared by a closed extrusion process. The die geometry and the length of the diffusion zone showed significant effects on the refractive index distributions of the polymer fibers. The non-quadratic refractive index portion of polymer fiber I was removed by a core-shell separation die design. The refractive... 

Figure 3. Relationships between An with (r/Rp) and (r/Rp) for the polymer fiber III prepared from the extrusion process with a core-shell separation die design. The temperature of the diffusion zone was 90 C.

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