飞秒激光脉冲照射诱导含芴结构树脂共聚物结构变化及机理的研究

Structure Change and Mechanism Analysis of Copolymer Containing Polyfluorene Induced by Femtosecond Laser Pulse

在室温下用聚焦的飞秒激光照射高折射率、低双折射的透明含芴结构树脂-对苯二甲酸乙二醇酯(PET)共聚物,探索飞秒激光制备高分子光学功能微结构的可能性。通过紫外-可见吸收光谱、红外光谱、电子自旋共振谱、光学显微镜、扫描电镜及透射电镜等分析手段,对该材料在飞秒激光照射后的结构变化及机理进行研究。结果发现:含芴结构树脂共聚物在飞秒激光照射后产生化学键断裂,生成未成对电子,并形成无定形碳;照射区在可见光区域的吸收增强;随激光能量密度的减少在激光会聚点附近诱导结构由慧尾状向单一细丝转变。演示了三维着色内雕。

In order to explore the possibility of for mi ng optical functional microstructures in pure and bulk polymer materials by irra diation of femtosecond laser pulses, a kind of copolymer contained polyfluorene, which has high refractive index and low birefringence, was irradiated by focuse d near-infrared femtosecond laser pulses at room temperature. The changes of mic rostructure in copolymer were investigated by ultraviolet and visible absorption spectrometer, infrared spectrometer, electron spin resonance spectrometer, opti cal microscope, scanning electron microscope and transmission electron microscop e, and the mechanism of the formation of induced structures was analyzed. The re sults indicated that after irradiation of the femtosecond laser pulses, the chem ical bonds of copolymer were broken, and a lot of unpaired electrons and amorpho us carbons were produced, consequently, the absorbance intensity in visible ligh t region enhanced. In addition, the formation of 3-dimensional colored image ins ide the copolymer was demonstrated.