Advancements in electronics and energy storage and conversion technologies brings with it myriads of exciting material design challenges. Charge-containing block polymers (BPs) offer unique features which can overcome some of these challenges and have thus aroused substantial interest within the field of designer soft materials. The properties of BPs are intricately coupled to the dynamic and rich nature of the nanostructured assemblies, which result from the phase separation between blocks. The introduction of strong secondary forces, such as electrostatics and hydrogen bonding (H-bonding), into BPs greatly influences their self-assembly behavior, and therefore affects their physical and electrochemical properties often in nontrivial ways. In this review, some of the prevailing research, which has expanded the understanding of structure-property relationships to include several design strategies for improving ionic conductivity and modulus in charged block polymers, is presented. The profound extent to which electrostatics and hydrogen bonding impact block polymer thermodynamics, an extent which is demonstrated by recent theoretical and experimental work, is also highlight. Insights gained from the research presented here help to lay the groundwork for a long and bright future in the field of advanced soft materials.

Amphiphilic silicone copolymers are an exciting class of biomedically relevant polymers that can be used for magnetic resonance imaging (MRI)-based cell labeling and oximetry studies. However, the solution characteristics and the ability to form stable nanoemulsions must be first demonstrated. Therefore, a series of amphiphilic siloxanes were successfully synthesized by grafting allylic poly(ethylene glycol) (PEG) with three (PEG(3)) or 11 (PEG( 11)) repeat units or allylic triethylammonium bromide (QUAT) substituents onto polyhydromethylsiloxane backbones at three different PEG:ammonium molar ratios by using a one-pot reaction pathway. The PEG length and the PEG:QUAT molar ratio were varied to tune the hydrophilicity and surface tension, and the polymer structures were confirmed by using 1 H NMR and FT-IR spectroscopy. The results show that the water contact angle increased upon attaching the PEG and QUAT groups, while the surface tension was most sensitive to the PEG(3) concentration. Also, the critical micelle concentration of the silicone graft copolymers decreased with an increase in the PEG content. Dynamic light scattering (DLS) and cryogenic transmission electron microscopy probed the solution structures and the ability to form nanoemulsions encapsulating polydimethylsiloxane (PDMS) oils. The graft copolymers containing PEG(3) showed consistent sizes by DLS, but the size distribution changed for the PEG(11) samples as the QUAT concentration increased. Finally, the graft copolymers successfully formed stable nanoemulsions containing PDMS with particle sizes that are appropriate for MRI-based cell labeling and oximetry applications.

Bile acids (BA), with their large hydrophobic steroid nucleus and polar groups are amphipathic molecules. In bile, these exist as micelles above their critical micellar concentration (CMC). In blood at low concentrations, these exist as monomers, initiating cellular signals. This micellar to monomer transition may involve complex thermodynamic interactions between bile salts alone or with phospholipids, i.e. mixed micelles and the aqueous environment. We therefore went on to test if therapeutically relevant changes in temperature could influence micellar behavior of bile salts, and in turn whether this affected the biological responses in cells, and in vivo. Sodium taurocholate (STC) belongs to a major class of bile salts. STC has a CMC in the 5–8 mM range and its infusion into the pancreatic duct is commonly used to study pancreatitis. We thus studied micellar breakdown of STC using isothermal titration calorimetry (ITC), dynamic light scattering and cryogenic transmission electron microscopy. Under conditions relevant to the in vivo environment (pH 7.4, Na 0.15 M), ITC showed STC to have a U shaped reduction in micellar breakdown between 37 °C and 15 °C with a nadir at 25 °C approaching ≈90% inhibition. This temperature dependence paralleled pancreatic acinar injury induced by monomeric STC. Mixed micelles of STC and 1-palmitoyl, 2-oleyl phosphatidylcholine, a phospholipid present in high proportions in bile, behaved similarly, with ≈75% reduction in micellar breakdown at 25 °C compared to 37 °C. In vivo pancreatic cooling to 25 °C reduced the increase in circulating BAs after infusion of 120 mM (5%) STC into the pancreatic duct, and duct ligation. Lower BA levels were associated with improved cardiac function, reduced myocardial damage, shock, lung injury and improved survival independent of pancreatic injury. Thus micellar breakdown of bile salts is essential for their entry into the systemic circulation, and thermodynamic interference with this may reduce their systemic entry and consequent injury during cholestasis, such as from biliary pancreatitis.

Nanocomposites integrate functional nanofillers into viscoelastic matrices for electronics, lightweight structural materials, and tissue engineering. Herein, the effect of methacrylate-functionalized (MA-SiO2) and vinyl-functionalized (V-SiO2) silica nanoparticles on the thermal, mechanical,...