CAJ | 학술논문

合成了一种含有长柔性间隔基和氰基三联苯液晶基元的发光性聚噻吩衍生物{-[thiopheneyl-CH_2-COO-(CH_2)_6-O-terphenyl-CN]_n-,PT(6)TPhCN}.利用傅里叶变换红外(FT-IR)光谱、核磁共振(~1H NMR)、差示扫描量热(DSC)仪、偏光显微镜(POM)、紫外-可见(UV-Vis)吸收光谱和荧光(PL)光谱对单体和聚合物的结构及性质进行了表征.单体都呈现出良好的液晶性能,由于长间隔基的存在,聚合物PT(6)TPhCN也呈现出良好SmA_d相.氰基三联苯的存在还赋予了聚合物良好的光致发光性能,同时,长间隔基也有效地降低了分子间的相互作用,进一步增强了聚合物的发光性能.另外,研究发现,在未引入任何手性元素的情况下,聚合物主链在圆二色(CD)光谱中还呈现出明显的Cotton效应,这可能是由于大体积液晶基元的位阻效应和取向作用,液晶基元环绕主链进行取向的同时诱导聚噻吩主链在长程范围内呈螺旋取向.
합성료일충함유장유성간격기화청기삼련분액정기원적발광성취새분연생물{-[thiopheneyl-CH_2-COO-(CH_2)_6-O-terphenyl-CN]_n-,PT(6)TPhCN}.이용부리협변환홍외(FT-IR)광보、핵자공진(~1H NMR)、차시소묘량열(DSC)의、편광현미경(POM)、자외-가견(UV-Vis)흡수광보화형광(PL)광보대단체화취합물적결구급성질진행료표정.단체도정현출량호적액정성능,유우장간격기적존재,취합물PT(6)TPhCN야정현출량호SmA_d상.청기삼련분적존재환부여료취합물량호적광치발광성능,동시,장간격기야유효지강저료분자간적상호작용,진일보증강료취합물적발광성능.령외,연구발현,재미인입임하수성원소적정황하,취합물주련재원이색(CD)광보중환정현출명현적Cotton효응,저가능시유우대체적액정기원적위조효응화취향작용,액정기원배요주련진행취향적동시유도취새분주련재장정범위내정라선취향.
A novel liquid crystalline(LC)polythiophene bearing cyanoterphenyl mesogenic pendants with a long flexible spacer{-[thiophene-CH_2-COO-(CH_2)_6-Oterphenyl-CN]_n-,PT(6)TPhCN} was designed and synthesized.Structures of the monomer and the polymer were characterized by nuclear magnetic resonance(NMR)and Fourier transform infrared(FT-IR)spectroscopy while the liquid crystalline and other properties were evaluated with thermo-gravimetry,differential scanning calorimetry(DSC),polarized optical microscopy(POM),ultraviolet visible(UV-Vis)spectroscopy,and photoluminescence(PL).The monomer shows enantiotropic smectic phases during the heating and cooling processes.Because of the long flexible spacer,the polymer PT(6)TPhCN exhibits a colorful SmA_d mesogenic phase texture.The cyanoterphenyl group results in the polymer having good photoluminescence.The spacer length also greatly influences the UV absorption and photoluminescence behavior of the polymers.A longer spacer may better segregate the backbone,which effectively enhances the stronger photoluminescence emission.More interestingly,without introducing any chiral groups,the polymer exhibits an obvious Cotton effect on the circular dichroism(CD) spectra,which results from the predominant screw sense of the backbone.This is probably due to the heavy bulky mesogenic pendant rotating around the polythiophene backbone and producing a backbone with a helical conformation in the long wavelength region.