摘要:
Aqueous prepolymer dispersions are provided, as are methods for making aqueous prepolymer dispersions. For example, an aqueous polyurethane prepolymer dispersion may be prepared by a process. The process may include contacting a soybean oil polyester polyol and an isocyanate reactive monomer together in a first mixture. The isocyanate reactive monomer may be functionalized with a tertiary amine salt of an isocyanate-unreactive organic acid. The process may include contacting the first mixture with a diisocyanate to form a neutralized polyurethane prepolymer. The process may include contacting the neutralized polyurethane prepolymer with water to form the aqueous polyurethane prepolymer dispersion.
摘要:
A series of resins were synthesized using a range of bio-based materials to control the molecular architecture, and therefore the properties, of the inventive resins. The utility of these resins was demonstrated in the formulation of powder coatings, such as ²-hydroxy amide crosslinked and hybrid types. Generally, the bio-based resins flowed out on heating faster than conventional petrochemically- based resins, allowing the use of lower temperatures in the curing oven than is typically possible and a more active catalyst system, especially in the carboxylic acid-epoxy crosslinked hybrid coatings formulations.
摘要:
Processing of wet biomass feedstock by liquid-phase catalytic hydrothermal gasification must address catalyst fouling and poisoning. One solution can involve heating the wet biomass with a heating unit to a pre-treatment temperature sufficient for organic constituents in the feedstock to decompose, for precipitates of inorganic wastes to form, for preheating the wet feedstock in preparation for subsequent removal of soluble sulfate contaminants, or combinations thereof. Processing further includes reacting the soluble sulfate contaminants with cations present in the feedstock material to yield a sulfate-containing precipitate and separating the inorganic precipitates and/or the sulfate-containing precipitates out of the wet feedstock. Having removed much of the inorganic wastes and the sulfate contaminants that can cause poisoning and fouling, the wet biomass feedstock can be exposed to the heterogeneous catalyst for gasification.
摘要:
A method of treating fibers to improve resistance to high temperatures and relative humidity includes providing poly(p-phenylene~2,6-benzobisoxazole) (PBO) fibers, exposing the PBO fibers to an atmosphere of supercritical CO 2 saturated with an epoxy silane, i.e. 3-glycidoxypropyl methyldimethoxysilane. The PBO fibers are subjected to a first pressurizing and heating stage at a first temperature (50°C) for a first period of time. The PBO fibers are then subjected to a second pressurizing and heating stage including increasing the temperature to a second temperature (110°C) and holding at the second temperature for an additional period of time. The PBO fibers include 2-5 wt% of 3-glycidoxypropyl methyldimethoxysilane after diffusing the CO 2 out of the PBO fibers. The fibers are particularly useful in making lightweight body armor system components.
摘要:
A system and method are disclosed that provide selective detection of gas-phase target analytes at concentrations below 1 part-per-trillion including explosives, explosives compounds, and other threat agents. The invention involves formation of chemical adduct ions between reactant ions and target analytes that permit detection of the target analytes in a sample.
摘要:
Improved lithium-sulfur energy storage systems can utilizes LixSy as a component in an electrode of the system. For example, the energy storage system can include a first electrode current collector, a second electrode current collector, and an ion-permeable separator separating the first and second electrode current collectors. A second electrode is arranged between the second electrode current collector and the separator. A first electrode is arranged between the first electrode current collector and the separator and comprises a first condensed-phase fluid comprising LixSy. The energy storage system can be arranged such that the first electrode functions as a positive or a negative electrode.
摘要:
Core annular flow is used to enable the subcutaneous delivery of a viscous fluid such as a protein therapeutic formulation. The high-viscosity fluid is surrounded by a low-viscosity fluid, and the low-viscosity fluid lubricates the passage of the high- viscosity fluid. This allows the use of protein formulations that have a higher concentration and a higher viscosity at comparatively reduced injection forces and reduced injection times. Several different embodiments of injection devices that provide core annular flow are described herein.