Optically transparent polycarbonates (PCs) and Copoly(Imide-Carbonate)s (Co-PICs) were synthesized by the melt polycondenzation method. Rigid (imide) and flexible (-O- and –C(CH₃)₂−) moieties were incorporated in the structure of bisimide diol comonomer using 4-aminophenol and 4,4′-(4,4′-isopropylidenediphenoxy) bis(phthalic anhydride). The structural properties of synthesized comonomers and polymers were confirmed by ¹H, ¹³C-NMR and FT-IR spectra. Thermal properties of polycarbonates and copolycarbonates were examined using DSC and TG analysis. Thermal properties (glass transition and thermal decomposition (T_d) temperature) of copolymers were enhanced without sacrificing properties of BPA-based PC (high transparency, ductility, and processability) by the incorporation of active functional bisimide diol comonomer (5–10 mole %) in the polycarbonate backbone. Different sets of PCs and Co-PICs thin film substrates were prepared by the solvent casting method and used to design frequency selective surface. The proposed flexible FSS offers shielding of 20 dB at 8.8 GHz. In addition, the FSS offers polarization independent operation with its symmetrical unit cell geometry.

中文翻译：

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用于电磁屏蔽应用的柔性聚碳酸酯和共聚（酰亚胺碳酸酯）基频率选择表面

采用熔融缩聚法合成了光学透明的聚碳酸酯（PC）和共聚（酰亚胺-碳酸酯）（Co-PIC）。使用4-氨基苯酚和4,4'-(4,4'-异亚丙基二苯_氧基)双₍邻苯二甲酸酐）。合成的共聚单体和聚合物的结构性质通过¹ H、¹³ C-NMR 和 FT-IR 光谱得到证实。使用 DSC 和 TG 分析检查聚碳酸酯和共聚碳酸酯的热性能。通过掺入活性功能性双酰亚胺二醇共聚单体（5-10 摩尔%），共聚物的热性能（玻璃化转变温度和热分解 (T _d ) 温度）得到了增强，同时又不牺牲 BPA 基 PC 的性能（高透明度、延展性和可加工性） ）在聚碳酸酯主链中。采用溶剂浇铸法制备了不同组的PCs和Co-PICs薄膜基底，并用于设计频率选择性表面。拟议的灵活 FSS 在 8.8 GHz 下提供 20 dB 的屏蔽。此外，FSS 凭借其对称的晶胞几何形状提供与偏振无关的操作。