Self-assembly in biobased nanocomposites for multifunctionality and improved performance.

Concerns of petroleum dependence and environmental pollution prompt an urgent need for new sustainable approaches in developing polymeric products. Biobased polymers provide a potential solution, and biobased nanocomposites further enhance the performance and functionality of biobased polymers. Here we summarize the unique challenges and review recent progress in this field with an emphasis on self-assembly of inorganic nanoparticles.

Activation and Assembly of Plasmonic-Magnetic Nanosurfactants for Encapsulation and Triggered Release.

Multifunctional surfactants hold great potentials in catalysis, separation, and biomedicine. Highly active plasmonic-magnetic nanosurfactants are developed through a novel acid activation treatment of Au-FeO dumbbell nanocrystals. The activation step significantly boosts nanosurfactant surface energy and enables the strong adsorption at interfaces, which reduces the interfacial energy one order of magnitude.

Unique Orientation of the Solid-Solid Interface at the Janus Particle Boundary Induced by Ionic Liquids.

This study reveals the unique role on Janus particles of the solid-solid interface at the boundary in determining particle interactions and assembly. In an aqueous ionic liquid (IL) solution, Janus spheres adopt intriguing orientations with their boundaries pinned on the glass substrate. It was further discovered that the orientation was affected by the particle amphiphilicity as well as the chemical structure and concentration of the IL.

Thin Biobased Transparent UV-Blocking Coating Enabled by Nanoparticle Self-Assembly.

A waterborne, UV-blocking, and visually transparent nanocomposite coating was formulated with ZnO nanoparticles and 2-hydroxyethyl cellulose (HEC). The coating is highly effective (<5% UV and ∼65% visible transmittance), and the film thickness (0.2-2.

Surfactant-Mediated Assembly of Amphiphilic Janus Spheres.

We investigate how amphiphilic Janus particle assembly structures, including clusters and striped two-dimensional (2D) crystals, are influenced by the addition of surfactant molecules. Janus particles are fabricated using silica particles coated with Au on one side, which is further modified with a hydrophobic self-assembled monolayer. Analysis on the cluster assembly structures suggests that in addition to hydrophobic attraction, van der Waals (VDW) attraction plays a significant role in the assembly process, which is modulated by the Au coating thickness.

Drying mediated orientation and assembly structure of amphiphilic Janus particles.

Amphiphilic Janus particles demonstrate unique assembly structures when dried on a hydrophilic substrate. Particle orientations are influenced by amphiphilicity and Janus balance. A three-stage model is developed to describe the process.