Depletion forces and macromolecular crowding govern the structure and function of biopolymers in biological cells and the properties of polymer nanocomposite materials. To isolate and analyze the influence of polymer shape fluctuations and penetrability on depletion-induced interactions and crowding by nanoparticles, we model polymers as effective penetrable ellipsoids, whose shapes fluctuate a...

We report on a novel slow dynamics of polymer xerogels, aerogels, and nanocomposite aerogels with iron oxide nanoparticles, as revealed by X-ray photon correlation spectroscopy. The polymer aerogel and its nanocomposite aerogels, which are porous in nature, exhibit hyper-diffusive dynamics at room temperature. In contrast, non-porous polymer xerogels exhibit an absence of this peculiar dynamics...

A general theory is developed for the equilibrium structure of dense polymer melts. This theory is based on an integral equation approach developed by Chandler and co-workers for molecular liquids. We are able to construct a tractable formalism for the polymer problem by employing the fact that a polymer molecule in a melt is ideal. This leads to a set of integral equations for the intermolecul...

Antifreeze (glyco) proteins AF(G)Ps are potent ice recrystallization inhibitors, which is a desirable property to enhance cryopreservation of donor tissue/cells. Here we present the rational synthesis of a new, biomimetic, ice-recrystallization inhibiting polymer derived from a cheap commodity polymer, based on an ampholyte structure. The polymer is used to enhance the cryopreservation of red b...

LLE Review, Volume 74 139 The last 20 years have seen a growth of mixed-media systems in which cholesteric liquid crystals (CLC’s) are one component. These include polymer-dispersed CLC’s1 in which the CLC’s are confined to microdroplets within a continuous isotropic polymer and CLC’s in gels2 in which there is a small amount of polymer to stabilize the CLC structure. In either case, the contin...

Helical polymer bundles are an important fixture in biomolecular systems. The particular structural geometry of helix bundles is dependent on many factors including the length of the polymer chain. In this study, we performed Monte Carlo simulations of a coarse-grained model for helical polymers to determine the influence of polymer length on tertiary structure formation. Helical structures of ...

A PEBAX-nano zeolite X mixed matrix membrane was fabricated and operationally characterized using single gas (CO2) permeation. X-ray diffraction (XRD) analysis was used to study the arrangement of polymer chains of mixed matrix membrane. The membranes were characterized by scanning electron microscopy (SEM) to study cross-sectional morphology. The single gas permeability were carried...

Dyeing properties of compounded polyethylene terephthalate fibers with a polyesteramide hyperbranched polymer were investigated in terms of their thermodynamic parameters, including standard affinity -Δμ⁰, enthalpy change ΔH⁰ and entropy change ΔS⁰. Results were then compared with corresponding properties of the virgin PET. The results showed that the isotherms were similar to that of virgin PE...

Biodegradable polymers have been widely used as scaffolding materials to regenerate new tissues. To mimic natural extracellular matrix architecture, a novel highly porous structure, which is a three-dimensional interconnected fibrous network with a fiber diameter ranging from 50 to 500 nm, has been created from biodegradable aliphatic polyesters in this work. A porosity as high as 98.5% has bee...

The surface-induced structure formation of polymer-dispersed liquid crystals (PDLCs) on a chemically patterned substrate was studied for the first time. The patterns on the substrate were successfully transferred to the PDLC film, resulting in alternating LC-rich and polymer-rich phases. This simple approach offers a new means of organizing micrometer-sized LC domains into well-ordered structur...