Federal Scientific Research Center «Crystallography and Photonics» Russian Academy of Sciences, Leninskiy Prospekt 59, Moscow 119333, Russia.
Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry Russian Academy of Sciences, Miklukho-Maklaya str. 16/10, Moscow 117997, Russia.
Molecules. 2019 Jul 5;24(13):2476. doi: 10.3390/molecules24132476.
Photopolymerization of nanocomposite materials using near infrared light is one of the unique technologies based on the luminescent properties of lanthanide-doped upconversion nanoparticles (UCNPs). We explored the UCNP-triggered radical polymerization both in oligomer bulk and on the nanoparticle surface in aqueous dispersion. Core/shell UCNPs NaYF:Yb and Tm/NaYF with emitting lines in the ultraviolet and blue regions were used to activate a photoinitiator. The study of the bulk photopolymerization in an initially homogeneous reaction mixture showed the UCNP redistribution due to gradient density occurring in the volume, which led to formation of UCNP superlattices and spheres "frozen" in a polymer matrix. We also developed a strategy of "grafting from" the surface, providing polymer shell growth directly on the nanoparticles. The photosensitization of the endogenous water-soluble photoinitiator riboflavin by the resonance energy transfer from UCNPs was demonstrated in the course of monomer glycidyl methacrylate polymerization followed by photocrosslinking with poly(ethylene glycol) diacrylate on the nanoparticle surface.
利用近红外光对纳米复合材料进行光聚合是基于镧系掺杂上转换纳米粒子（UCNP）发光特性的独特技术之一。我们探索了在低聚物本体和纳米粒子表面的 UCNP 引发的自由基聚合，在水性分散体中进行。具有在紫外和蓝光区域发射线的核/壳 UCNP NaYF:Yb 和 Tm/NaYF 被用来激活光引发剂。在初始均匀反应混合物中的本体光聚合研究表明，由于在体积中发生的密度梯度，UCNP 会重新分布，这导致了 UCNP 超晶格和“冻结”在聚合物基质中的球体的形成。我们还开发了一种从表面“接枝”的策略，直接在纳米粒子上提供聚合物壳的生长。在单体甲基丙烯酸缩水甘油酯聚合过程中，UCNP 从共振能量转移对内源性水溶性光引发剂核黄素进行敏化，随后在纳米粒子表面与聚乙二醇二丙烯酸酯进行光交联。
