摘要:
Described herein are a method, an apparatus, and a system for metal processing that improves one or more properties of a sintered metal part by controlling the process conditions of the cooling zone of a continuous furnace using one or more cryogenic fluids. In one aspect, there is provided a method comprising: providing a furnace wherein the metal part is passed therethough on a conveyor belt and comprises a hot zone and a cooling zone wherein the cooling zone has a first temperature; and introducing a cryogenic fluid into the cooling zone where the cryogenic fluid reduces the temperature of the cooling zone to a second temperature, wherein at least a portion of the cryogenic fluid provides a vapor within the cooling zone and cools the metal parts passing therethrough at an accelerated cooling rate.
摘要:
Described herein are a method, an apparatus, and a system for metal processing that improves one or more properties of a sintered metal part by controlling the process conditions of the cooling zone of a continuous furnace using one or more cryogenic fluids. In one aspect, there is provided a method comprising: providing a furnace wherein the metal part is passed therethough on a conveyor belt and comprises a hot zone and a cooling zone wherein the cooling zone has a first temperature; and introducing a cryogenic fluid into the cooling zone where the cryogenic fluid reduces the temperature of the cooling zone to a second temperature, wherein at least a portion of the cryogenic fluid provides a vapor within the cooling zone and cools the metal parts passing therethrough at an accelerated cooling rate.
摘要:
An aqueous polymeric coating composition having a polymer for forming a polymer matrix having carboxylate functionality and nano-scale zinc oxide particles dispersed in the polymer. The particles provide the polymer with at least partial crosslinking and alcohol resistance when incorporated into the polymer matrix upon curing. A polymeric material formed from the aqueous composition and a coated article are also disclosed.
摘要:
A method for preparing a polyurethane foam which comprises reacting an organic polyisocyanate and a polyol in the presence of a blowing agent, a cell stabilizer and a catalyst composition comprising at least one compound of either of the following formulas IA and IB: ##STR1## where R is hydrogen, methyl or hydroxymethyl. The preferred catalysts comprise 3-hydroxymethyl quinuclidine, 3-methyl-3-hydroxymethyl quinuclidine and 4-hydroxymethyl quinuclidine.
摘要:
The disclosure relates to acid-based polymeric dispersants containing 2-[2-(2-methoxyethoxy)ethoxy]acetic acid for dispersing metal oxide nanoparticles in organic solvents such as methyl ethyl ketone (MEK) and butyl acetate.
摘要:
The present invention relates to an improvement in flexible, semi-flexible and rigid foams formed by the catalytic reaction of an aromatic polyisocyanate, a polyol and a blowing agent and a process for preparing such polyisocyanate. The improvement resides in using an effective amount of a bismuth carboxylate or bismuth sulfonate having less than 34% free acid as the catalyst.
摘要:
This invention is directed to methods of incorporating a trigger such as boric acid, boric acid salts, sodium sulfate, or other salts, into a nonwoven web substrate for the preparation of dry nonwoven products which are redispersible when put in contact with large amounts of water or liquid. In one method, the trigger is in a dry powder form and is incorporated into the nonwoven fibers followed by treatment of the fibers with an aqueous redispersible binder, and binding and drying the web. Another method is to saturate a dry bonded nonwoven web with an aqueous solution of the trigger and then dry the saturated web. Yet another method is to apply an aqueous solution of the trigger to the web followed by applying a redispersible aqueous binder to the web and then heating and drying the web.
摘要:
The disclosure relates to acid-based polymeric dispersants containing 2-[2-(2-methoxyethoxy)ethoxy]acetic acid for dispersing metal oxide nanoparticles in organic solvents such as methyl ethyl ketone (MEK) and butyl acetate.
摘要:
A polyurethane catalyst composition comprises N,N'-bis(3-dimethylaminopropyl) urea and 3-dimethylaminopropyl urea in a ratio that can be varied to systematically control flowability, airflow, and force-to-crush physical properties for flexible polyurethane foam to enhance processibility. Increasing the N,N'-bis(3-dimethylaminopropyl) urea to 3-dimethylaminopropyl urea ratio increases the airflow and decreases the force-to-crush values of the foam whereas decreasing the N,N'-bis(3-dimethylaminopropyl) urea to 3-dimethylaminopropyl urea ratio improves the flowability of the foam.
摘要:
Treating metal or metal oxides such as ZnO with PIBSA and analogous molecules yields a hydrophobic powder. The powder can provide improved optical clarity when incorporated into a polymer matrix in comparison to untreated hydrophilic ZnO.