核壳型荧光微球的制备及性能分析

Preparation and performance analysis of core-shell fluorescent microspheres

关键词:  荧光微球  碳量子点  水化膨胀性  荧光强度  调驱能力 

Key words:  fluorescent microspheres  carbon quantum dots  hydration expansion  fluorescence intensity  displacement ability

摘要:

目的 赋予聚合物微球一种荧光特性使其具有示踪性能,根据对采出液的检测,可清晰了解聚合物微球在地层中的吸附滞留、运移等实际情况。但是,如何最大程度保留原微球调驱能力的同时,将荧光材料与聚合物微球有效融合是目前亟待解决的一项难题。方法 以阳离子功能单体、丙烯酰胺等作为主要成分的普通核壳微球为载体,以碳量子点为荧光材料,通过共聚反应完成荧光微球材料的制备。测定了其荧光强度并进行了Zeta电位、水化膨胀性及封堵性能的对比实验。结果 碳量子点的荧光产率较高,最低检测限可达0.05%；Zeta电位数据证明了荧光单体成功固定至微球的核心层,确保了荧光材料与原型微球的有效融合；荧光微球与普通核壳微球的封堵率相差在3%之内,两者水化膨胀性和封堵性能基本相同。结论 碳量子点荧光材料引入至核心层并未改变聚合物微球的自身特性且检测极限值低,有望进行后续的现场应用。 

Abstract:

Objective By endowing polymer microspheres with a fluorescent characteristic that enables them to have tracer performance, the actual situation of adsorption, retention, and migration of polymer microspheres in the formation can be clearly understood based on the detection of the produced liquid. However, a difficult problem that needs to be solved urgently is how to maximize the displacement ability of keeping the original microspheres with the effective integration of fluorescent materials and polymer microspheres. Methods The preparation of fluorescent microspheres was achieved through copolymerization reaction using ordinary core-shell microspheres with cationic functional monomers, acrylamide, and other main components as carriers and carbon quantum dots as fluorescent materials. The fluorescence intensity was measured and a comparative experiment of Zeta potential, hydration expansion, and sealing performance was carried out. Results The fluorescence yield rate of carbon quantum dots was high, with a minimum detection limit of 0.05%; The Zeta potential data demonstrated that the fluorescent monomer was successfully fixed to the core layer of the microspheres, ensuring effective fusion of the fluorescent material with the prototype microspheres; The difference in sealing efficiency between fluorescent microspheres and ordinary core-shell microspheres was within 3%, and the hydration expansion and sealing performance of them were basically same. Conclusion sThe introduction of the carbon quantum dot fluorescent material into the core layer has not changed the characteristics of the polymer microspheres, and the detection limit value is low, which is expected to be used in subsequent field applications.