Patent classifications
C08G64/40
METHOD OF PRODUCING CRYSTALLINE POLYCARBONATE POWDERS
A method of preparing a partially crystalline polycarbonate powder, including: dissolving an amorphous polycarbonate in a halogenated alkane solvent to form a solution; combining the solution with a crystallizing non-solvent that is miscible with the halogenated alkane solvent, under high shear mixing conditions effective to form a partially crystalline polycarbonate precipitate having a D90 particle size of less than 150 micrometers; an average particle diameter of less than or equal to 100 micrometers, or an average particle diameter of 0 to 100 micrometers; and at least 20% crystallinity, or at least 25% crystallinity, or 25 to 35% crystallinity.
METHOD OF PRODUCING CRYSTALLINE POLYCARBONATE POWDERS
A method of preparing a partially crystalline polycarbonate powder, including: dissolving an amorphous polycarbonate in a halogenated alkane solvent to form a solution; combining the solution with a crystallizing non-solvent that is miscible with the halogenated alkane solvent, under high shear mixing conditions effective to form a partially crystalline polycarbonate precipitate having a D90 particle size of less than 150 micrometers; an average particle diameter of less than or equal to 100 micrometers, or an average particle diameter of 0 to 100 micrometers; and at least 20% crystallinity, or at least 25% crystallinity, or 25 to 35% crystallinity.
POLYESTER POLYOLS FROM RECYCLED POLYMERS AND WASTE STREAMS
The present invention relates to polyester polyols made from aromatic polyacid sources such as thermoplastic polyesters. The polyols can be made by heating a thermoplastic polyester such as virgin polyethylene terephthalate, recycled polyethylene terephthalate, or mixtures thereof, with a glycol to give a digested intermediate which is then reacted with a digestible polymer, which can be obtained from various recycle waste streams. The polyester polyols comprise a glycol-digested polyacid source and a further digestible polymer. The polyester polyols provide a sustainable alternative to petrochemical or biochemical based polyester polyols.
Producing semi-crystalline pulverulent polycarbonate and use thereof in additive manufacturing
Ways of preparing a partially crystalline polycarbonate powder are provided that include dissolving an amorphous polycarbonate in a polar aprotic solvent to form a first solution of solubilized polycarbonate at a first temperature. The first solution is then cooled to a second temperature, the second temperature being lower than the first temperature, where a portion of the solubilized polycarbonate precipitates from the first solution to form a second solution including the partially crystalline polycarbonate powder. Certain partially crystalline polycarbonate powders resulting from such methods are particularly useful in additive manufacturing processes, including powder bed fusion processes.
Producing semi-crystalline pulverulent polycarbonate and use thereof in additive manufacturing
Ways of preparing a partially crystalline polycarbonate powder are provided that include dissolving an amorphous polycarbonate in a polar aprotic solvent to form a first solution of solubilized polycarbonate at a first temperature. The first solution is then cooled to a second temperature, the second temperature being lower than the first temperature, where a portion of the solubilized polycarbonate precipitates from the first solution to form a second solution including the partially crystalline polycarbonate powder. Certain partially crystalline polycarbonate powders resulting from such methods are particularly useful in additive manufacturing processes, including powder bed fusion processes.
MANUFACTURABILITY OF AMORPHOUS POLYMERS IN POWDER BED FUSION PROCESSES
A method of making an article, the method comprising converting a first amorphous polymer to an at least partially crystalline polymeric powder composition and powder bed fusing the at least partially crystalline polymer powder composition to form a three-dimensional article comprising a second amorphous polymer.
MANUFACTURABILITY OF AMORPHOUS POLYMERS IN POWDER BED FUSION PROCESSES
A method of making an article, the method comprising converting a first amorphous polymer to an at least partially crystalline polymeric powder composition and powder bed fusing the at least partially crystalline polymer powder composition to form a three-dimensional article comprising a second amorphous polymer.
Method for producing polycarbonate
Provided is a method of producing a polycarbonate that enables efficient drying of a polycarbonate powder and has no risk of deteriorating the quality of a polycarbonate molded article to be obtained. The method of producing a polycarbonate includes: a step of causing an alkali aqueous solution of a dihydric phenol and phosgene to react with each other in the presence of an organic solvent to produce an organic solvent solution containing a polycarbonate; a powdering step of powdering the organic solvent solution containing the polycarbonate to provide a polycarbonate powder; and a pre-drying step of drying the polycarbonate powder to remove the remaining organic solvent, in which a drying temperature in the pre-drying step is set to a temperature lower than the glass transition temperature of the polycarbonate containing 1.5 mass % of the organic solvent by from 5 C. to 15 C.
POLYCARBONATE RESIN COMPOSITION, METHOD FOR PRODUCING SAME, AND MOLDED OBJECT
The present invention aims at providing a polycarbonate resin composition having excellent transparency and possessing high levels of biogenic substance content rate, heat resistance, wet heat resistance and impact resistance in a balanced manner, a production method thereof, and a molded body of the polycarbonate resin composition. The present invention is a polycarbonate resin composition including a polycarbonate resin (A) containing a constitutional unit derived from a compound represented by the following formula (1), and an aromatic polycarbonate resin (B), a production method thereof, and a molded body of the resin composition:
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METHOD FOR DEWATERING A POLYMER AND THE POLYMER MADE THEREFROM
In an embodiment, a method of dewatering a wet polymer composition comprises introducing the wet polymer composition via a polymer feed location to a powder conveying section of an extruder; wherein the wet polymer composition comprises greater than or equal to 1 wt % of water based on the total weight of the wet polymer composition; venting the water through a conveying section vent to form a dry polymer composition; melt kneading the dry polymer composition in a melt kneading section of the extruder to form a polymer melt; conveying the polymer melt in a melt conveying section of the extruder; and adding an additive in one or both of the powder conveying section and the melt conveying section.