Sabadini Júlia Bonesso, Oliveira Cristiano Luis Pinto, Loh Watson
Institute of Chemistry, University of Campinas (UNICAMP), P.O Box 6154, Campinas, SP, Brazil.
Institute of Physics, University of São Paulo (USP), São Paulo, SP, Brazil.
J Colloid Interface Sci. 2025 Jan 15;678(Pt A):1012-1021. doi: 10.1016/j.jcis.2024.08.248. Epub 2024 Aug 30.
Ethoxylated complex coacervate core micelles (C3Ms), formed by the electrostatic coacervation of a charge-neutral diblock copolymer and an oppositely charged homopolymer, exhibit morphology governed by molecular packing principles. Additionally, this morphology is temperature-dependent, leading to transitions similar to those observed in classical ethoxylated surfactant aggregates.
To explore the thermal effects on the size and morphology of C3Ms, we employed dynamic light scattering (DLS), small-angle X-ray scattering (SAXS), and cryogenic transmission electron microscopy (cryo-TEM). These techniques were applied to C3Ms formed by copolymers with varying poly(ethylene oxide) (EO) lengths.
Increasing the temperature-induced a transition from spherical to elongated aggregates, contingent on the EO block length. This morphological transition in EO-containing C3Ms parallels the behavior of classical ethoxylated surfactant aggregates. Despite the fundamental differences between hydrophobically driven and electrostatic coacervate micelles, our findings suggest that similar molecular packing principles are universally applicable across both systems. Our results offer valuable insights for predicting the structural properties of these coacervate platforms, which is crucial for envisioning their future applications.
由电荷中性的二嵌段共聚物与带相反电荷的均聚物通过静电凝聚形成的乙氧基化复合凝聚核胶束（C3M），其形态受分子堆积原理支配。此外，这种形态还取决于温度，会导致与在经典乙氧基化表面活性剂聚集体中观察到的类似转变。
为了探究温度对C3M大小和形态的影响，我们采用了动态光散射（DLS）、小角X射线散射（SAXS）和低温透射电子显微镜（cryo-TEM）。这些技术被应用于由具有不同聚环氧乙烷（EO）长度的共聚物形成的C3M。
温度升高会导致从球形聚集体向拉长聚集体的转变，这取决于EO嵌段的长度。含EO的C3M中的这种形态转变与经典乙氧基化表面活性剂聚集体的行为相似。尽管疏水驱动的胶束和静电凝聚胶束之间存在根本差异，但我们的研究结果表明，相似的分子堆积原理在这两种体系中普遍适用。我们的结果为预测这些凝聚平台的结构性质提供了有价值的见解，这对于设想它们未来的应用至关重要。
