Institute of Chemistry, Eötvös University, 1117 Budapest, Pázmány s. 1/A, Hungary.
Langmuir. 2011 Jun 21;27(12):7917-25. doi: 10.1021/la2010387. Epub 2011 May 18.
Monodisperse microgel latex with homogeneous cross-link density distribution within the particles was prepared by feeding the monomer and cross-linker into the reaction mixture in a regulated way during the polymerization. To determine the appropriate monomer feeding parameters, the kinetics of the particle formation was investigated by HPLC. The swelling and optical characteristics of the prepared homogenously cross-linked microgel particles were compared to the properties of inhomogenously cross-linked microgels prepared by the normal precipitation polymerization method. The distribution of the cross-link density within the particles inserts a great influence on the characteristics of the system. The degree of swelling of the homogeneous particles is significantly higher than that of the heterogeneous microgel particles. Furthermore, at room temperature the pNIPAm latex containing the homogeneously cross-linked particles is transparent, while the heterogeneously cross-linked particles form a highly turbid system at the same 0.1 wt% concentration.
通过在聚合过程中以受控的方式将单体和交联剂进料到反应混合物中，制备了具有颗粒内均匀交联密度分布的单分散微凝胶乳胶。为了确定合适的单体进料参数，通过 HPLC 研究了颗粒形成的动力学。比较了制备的均匀交联微凝胶颗粒的溶胀和光学特性与通过常规沉淀聚合方法制备的不均匀交联微凝胶的性质。交联密度在颗粒内的分布对体系的特性有很大的影响。均匀颗粒的溶胀度明显高于不均匀微凝胶颗粒。此外，在室温下，含有均匀交联颗粒的 pNIPAm 乳胶是透明的，而相同浓度为 0.1wt%的异质交联颗粒形成高度浑浊的体系。
