Multi-layer films of block copolymer micelles adsorbed to colloidal templates

Polyelectrolyte multilayer-like films from layer-by-layer processing of protected polyampholytic block copolymers

Polyelectrolyte multilayer films (PEMs) are conventionally prepared by a layer-by-layer (LbL) deposition of alternating polycation and polyanion solutions. We introduce herein a block copolymer (BCP) approach employing a BCP with an H-bond acceptor block and a protected H-donor block as a masked polyampholyte to form new types of PEMs.

Random sequential adsorption of starlike particles

Random packing of surfaceless starlike particles built of 3 to 50 line segments was studied using random sequential adsorption algorithm. Numerical simulations allow us to determine saturated packing densities as well as the first two virial expansion coefficients for such objects. Measured kinetics of the packing growth supports the power law known to be valid for particles with a finite surface; however, the dependence of the exponent in this law on the number of star arms is unexpected. The density autocorrelation function shows fast superexponential decay as for disks, but the typical distance between closest stars is much smaller than between disks of the similar size, especially for a small number of arms.

Lipid crystallization: from self-assembly to hierarchical and biological ordering

Lipid crystallization is ubiquitous in nature, observed in biological structures as well as in commercial products and applications. In a dehydrated state most of the lipids form well ordered crystals, whereas in an aqueous environment they self-assemble into various crystalline, liquid crystalline or sometimes macroscopically disordered phases. Lipid self-organization extends further to hierarchical levels including structured emulsions and nanostructured particles. Many consumer products including cosmetics, foods and medicines account for such lipid architectures. Cell membranes primarily consist of planar lipid bilayers; however sub-cellular biomembranes are more of a convoluted type. Some of the biological entities have lipids in truly crystalline form; yet liquid crystalline lipid phases are prevalent, in general. Crystallization of fats - triglyceride lipids - has been relatively well documented and reviewed more often, but this review features other areas where lipid organization is crucial and diverse. Some recent advances along with a few explicit examples of model lipid phases and biological evidences are also reported.