羧基功能化聚苯乙烯荧光微球的制备及表征

以苯乙烯、丙烯酸为单体,引入疏水性荧光染料罗丹明6G(Rh6G),采用微乳聚合法制备羧基聚苯乙烯荧光微球,并分析了表面活性剂、引发剂、丙烯酸用量对产物粒径分布的影响,考察了羧基聚苯乙烯荧光微球的浓度对荧光强度的影响。通过粒度分析仪、扫描电子显微镜、红外光谱仪、紫外吸收光谱以及荧光光谱仪对样品的纳米特性、形貌、结构和荧光性能进行了表征。结果表明,用微乳聚合法制备出50~250nm的羧基聚苯乙烯荧光微球,粒径均一且呈单分散性。紫外光谱图测试表明,在533nm左右有吸收峰。荧光光谱测试表明,羧基功能化的荧光聚苯乙烯微球浓度≤0.01%,其荧光最大激发峰为527nm,最大发射峰在555nm处;浓度高于0.01%时,荧光光谱出现红移,且荧光强度减弱。

Preparation and characterization of carboxylate-modified PS fluorescent microsphere

Carboxylate-modified polystyrene(PS)fluorescent microspheres were synthesised by microemulsion polymerization using rhodamine 6G(Rh6G)as hydrophobic fluorescent dye,acrylic acid and styrene as monomer.The effects of surfactant,initiator and acrylic acid monomer on the particle size distribution were analyzed.The structure,morphology and performance of carboxylate-modified PS fluorescent microspheres were characterized by DLS,SEM,FT-IR,UV and fluorescence spectrum.The microspheres with the size from 50 nm to 250 nm were obtained.The absorption peak was around 533 nm by UV spectrogram.Fluorescence spectra results showed that the concentration of the microspheres had an important effect on the fluorescence intensity.When the concentration was no more than 0.01%,the maximum fluorescence excitation peak was 527 nm,and the maximum emission peak was 555 nm.When the concentration was above 0.01%,the fluorescence spectrum was redshift,and the fluorescence intensity was decreased.