毛细管阵列微反应器制备聚合物荧光纳米粒子

设计并制作了新型同轴毛细管阵列微反应器，结合纳米沉淀法制备了聚合物荧光纳米粒子。实验所用的聚合物为聚（9,9-二辛基芴-共-苯并噻二唑）（PFBT），溶剂为四氢呋喃（THF），反溶剂为去离子水，稳定剂为聚苯乙烯-马来酸酐共聚物（PSMA）。产物纳米粒子使用动态光散射技术（DLS）进行表征。结果表明，同轴毛细管阵列微反应器中间层溶剂的存在，改变了聚合物溶液与反溶剂的混合方式，克服了微流体注射纳米沉淀法中注射管口的产物沉淀堵塞问题。在聚合物浓度高达500 mg/L时，反应器仍可长时间持续运行。同时，纳米颗粒的粒径可以通过改变聚合物溶液、溶剂和反溶剂的流量及聚合物溶液浓度等操作条件来精确调控。当 PFBT 溶液的浓度为50 mg/L，去离子水与聚合物溶液的流量比为750：1时，制备的纳米颗粒的尺寸可小至13 nm。该微反应器实现了聚合物纳米粒子的长时间连续可控制备。

Preparation of fluorescent polymer dots based on a capillary array microreactor

A coaxial capillary array microreactor was designed and constructed to prepare fluorescent polymer dots (Pdots) by a nanoprecipitation method. Poly(9,9-dioctylfluorene-co-benzothiadiazole) (PFBT) was used as polymer, tetrahydrofuran (THF) as solvent, deionized water as anti-solvent and polystyrene-maleic anhydride copolymer (PSMA) as stabilizer in the experiments. The prepared Pdots were characterized by dynamic light scattering (DLS). The results showed that the accumulation and blockage of products were avoided at the tip of the injection nozzle in the microreactor due to the middle solvent stream which changed the mixing process between polymer solution and antisolvent. The microreactor kept on running well for a long time even at the high concentration of polymer solution of 500 mg/L. The size of the nanoparticles can be adjusted by varying the concentration of the polymer solution and the flow rates of the solution, solvent, and antisolvent. The diameters of the prepared nanoparticles were decreased down to 13 nm at the concentration of the PFBT solution of 50 mg/L and the flow ratio of deionized water to polymer solution of 750:1. The microreactor can be used to prepare continually polymer nanoparticles with controllable size.