Modular Adjustment of Swelling Behaviors of Surface-Modified Solvent-Responsive Polymeric Nanoparticles Based on Cellulose 10-Undecenoyl Ester

Functional polymeric nanoparticles (NPs) have attracted intense interest because of their broad applications. However, most of them focused on characteristics, behaviors, properties, or functionalities of the NPs, while neglecting the interaction between NPs and solvents and thus the influence of solvents on the physical–chemical properties of NPs. In this paper, NPs based on cellulose 10-undecenoyl ester with total substitution of hydroxyl groups by undecenoyl moieties were prepared in various organic dispersants via nanoprecipitation. These NPs were further surface-modified with diverse functionalities via thiol–ene reactions on the terminal vinyl groups of undecenoyl moieties. The swelling behaviors of the resultant surface-modified NPs were systematically investigated via adding corresponding swelling solvents to the dispersions, fitting the swelling modes to different types of functions, and analyzing the factors influencing the swelling processes. It is concluded that different interactions including hydrogen bond interaction between swelling solvents and surface-modified outer layers as well as nonmodified interior parts of NPs are essential for different swelling trends. The swelling extents and tolerant capacities for swelling solvents in dispersant could be affected by the characters of dispersants, the surface functionalities of NPs, and the interaction between them. Thus, our investigation provides a general understanding of the swelling behaviors of surface-modified solvent-responsive NPs derived from polymeric cellulose derivatives.