Contruction of "Crystalline" Heat Resistant Plastic Optical Fiber and Their Transparent Film with Excellent Light Conductivity

我们开发了一种具有优异耐热性和尺寸稳定性的“结晶”塑料光纤。为了在不久的将来实际使用这种晶体光纤，固态结构的精确控制是必不可少的，因为必须减少晶体/非晶界面处的光折射。采用广角X射线衍射（WAXD）和小角X射线散射（SAXS）方法研究了聚全氟乙基乙烯基醚（EFA）透明结晶纤维在拉伸过程中的精细结构和片层排列的变化。EFA在纤维中结晶为片晶，并形成较厚的片晶（厚度：至少27 nm）。这种聚合物可以形成“开关板型”薄片。在EFA纤维的拉伸过程中，照片中出现了四点SAXS图，这意味着形成了一种特殊类型的层结构，一种称为人字形的交替倾斜的薄片排列。此外，先前提出的一般氟化聚合物的堆积模式需要从准六方晶格修改为正交晶格，以分配所有的反射率。

We developed a "crystalline" plastic optical fiber with excellent heat resistance and dimensional stability. For the practical use of this crystalline optical fiber in the near future, an accurate control of the solid-state structure is indispensable because of the necessity of reducing light refraction at the crystalline/amorphous interface. In the present study, changes in the fine structure and lamella arrangement upon drawing poly[tetrafluoroethylene-co-(perfluoroethylvinylether)] (abbrev. EFA) transparent crystalline fibers were investigated by using wide-angle X-ray diffraction (WAXD) and small-angle X-ray scattering (SAXS) methods. The EFA was crystallized as a lamella crystal in the fibers and formed a thicker lamella (thickness : at least 27nm). This polymer might form a "switchboard-type" lamella. Upon the drawing of the EFA fibers, four-point SAXS diagrams developed in the photograph, which implied that a particular type of layer structure, an alternately tilted lamella arrangement known as the herringbone, was formed. Moreover, the previously proposed packing mode of general fluorinated polymers was required to be modified from quasi-hexagonal to orthorhombic in a reciprocal lattice in order to assign all reflective indexes.