Conformational Entropy as a Means to Control the Behavior of Poly(diketoenamine) Vitrimers In and Out of Equilibrium.

Control of equilibrium and non-equilibrium thermomechanical behavior of poly(diketoenamine) vitrimers is shown by incorporating linear polymer segments varying in molecular weight (MW) and conformational degrees of freedom into the dynamic covalent network. While increasing MW of linear segments yields a lower storage modulus at the rubbery plateau after softening above the glass transition (T ), both T and the characteristic time of stress relaxation are independently governed by the conformational entropy of the embodied linear segments. Activation energies for bond exchange in the solid state are lower for networks incorporating flexible chains; the network topology freezing temperature decreases with increasing MW of flexible linear segments but increases with increasing MW of stiff segments.

Ion Transport and the True Transference Number in Nonaqueous Polyelectrolyte Solutions for Lithium Ion Batteries.

Nonaqueous polyelectrolyte solutions have been recently proposed as high Li transference number electrolytes for lithium ion batteries. However, the atomistic phenomena governing ion diffusion and migration in polyelectrolytes are poorly understood, particularly in nonaqueous solvents. Here, the structural and transport properties of a model polyelectrolyte solution, poly(allyl glycidyl ether-lithium sulfonate) in dimethyl sulfoxide, are studied using all-atom molecular dynamics simulations.

Elucidating Solvation Structures for Rational Design of Multivalent Electrolytes-A Review.

Fundamental molecular-level understanding of functional properties of liquid solutions provides an important basis for designing optimized electrolytes for numerous applications. In particular, exhaustive knowledge of solvation structure, stability, and transport properties is critical for developing stable electrolytes for fast-charging and high-energy-density next-generation energy storage systems. Accordingly, there is growing interest in the rational design of electrolytes for beyond lithium-ion systems by tuning the molecular-level interactions of solvate species present in the electrolytes.

Phosphorus reclamation through hydrothermal carbonization of animal manures.

Projected shortages of global phosphate have prompted investigation of methods that could be employed to capture and recycle phosphate, rather than continue to allow the resource to be essentially irreversibly lost through dilution in surface waters. Hydrothermal carbonization of animal manures from large farms was investigated as a scenario for the reclamation of phosphate for agricultural use and mitigation of the negative environmental impact of phosphate pollution. Hydrothermal reaction conditions were identified for poultry, swine, and cattle manures that resulted in hydrochar yields of 50-60% for all three manures, and >90% of the total phosphorus present in these systems was contained in the hydrochars as precipitated phosphate salts.

Industrial symbiosis: corn ethanol fermentation, hydrothermal carbonization, and anaerobic digestion.

The production of dry-grind corn ethanol results in the generation of intermediate products, thin and whole stillage, which require energy-intensive downstream processing for conversion into commercial animal feed products. Hydrothermal carbonization of thin and whole stillage coupled with anaerobic digestion was investigated as alternative processing methods that could benefit the industry. By substantially eliminating evaporation of water, reductions in downstream energy consumption from 65% to 73% were achieved while generating hydrochar, fatty acids, treated process water, and biogas co-products providing new opportunities for the industry.