2种新型Cardo型氟化聚吡啶酰胺的合成与表征

通过Yamazaki聚合方法,将4-（4-三氟甲基苯基）-2,6-二（4-胺基苯基）吡啶（TMPBAPP）分别和9,9-二[4-（4-羧基苯氧基）苯基]呫吨（BCPX）和1,1-二[4-（4-羧基苯氧基）苯基]环己烷（BCPC）进行缩聚反应,合成了2种高相对分子质量的Cardo型氟化聚吡啶酰胺,并以FTIR、DSC、WAXD等方法对其结构和性能进行了表征.结果表明：2种聚合物的玻璃化转变温度分别为252℃和290℃,对数比浓黏度分别为0.78 d L·g^-1和0.98 d L·g^-1.在氮气气氛中,5%的热失重温度分别为435℃和500℃,800℃时的残炭率分别为55%和58%,均为无定形结构;2种聚合物均易溶于N-甲基吡咯烷酮、N,N-二甲基乙酰胺、间甲酚等有机溶剂中,并可浇注得到韧性好而透明的薄膜,其拉伸强度分别为78 MPa和86 MPa,拉伸膜量分别为2.2 GPa和2.6 GPa,断裂伸长率分别为9%和13%.同时,合成的聚合物具有良好的透光率（截断波长分别为340 nm和376 nm）,体积电阻、表面电阻和介电常数分别为8.45-8.78×10^15Ω·cm、9.52-9.82×10^14Ω和3.46-3.60（100 Hz）,呈现了良好的电绝缘性能.

Design of Polarization-independent Wavelength-interleave Coupler in Fluorinated Polyimide Waveguide

Based on the measurement of dispersion characteristic and birefractive index of the fluorinated polyimide film,a statistical optimum design method is proposed and used to realize the design of 32- and 36-wavelengths optical waveguide wavelength-interleave coupler(i,e.,interleaver) with the optimization of polarization fluctuation and wavelength interval of 0.8 nm at 1 550 nm.The largest cross coupling ratios of the two interleavers are respectively less than 1.8% and 3.5%,while the least through coupling ratios are respectively greater than 98.2% and 96.5%.The output differences due to polarization fluctuation are less than ±1.7% and ±3.2%.