摘要:
A method of making a catalyst comprising mixing a metal oxide precursor and a pore former to form a metal oxide precursor mixture and calcining the metal oxide precursor mixture in the presence of a flowing gas having a flow rate to form the catalyst comprising metal oxide. The catalyst comprises a first distribution of pores having a median pore diameter of 10 to 50 angstroms and a second distribution of pores having a median pore diameter of 1 to 500 angstroms. The median pore diameter of the second distribution of pores is inversely related to the flow rate of the gas.
摘要:
A method for preparing a poly(arylene ether) with a reduced level of powder fines is described. In one embodiment, the method comprises oxidatively coupling a monohydric phenol in the presence of a solvent and a complex metal catalyst, to produce a poly(arylene ether) resin; and then removing a portion of the solvent to produce a concentrated solution having a cloud point Tcloud. The concentrated solution is then combined with an anti-solvent to precipitate the poly(arylene ether) in the form of a precipitation mixture. The concentrated solution usually has a temperature of at least about (Tcloud−10° C.) immediately before it is combined with the anti-solvent. The precipitation mixture has a temperature of at least about (Tcloud−40° C.) after its formation. Related poly(arylene ether) copolymers are also described.
摘要:
A process for producing a poly(arylene ether) resins includes oxidatively coupling a monohydric phenol in the presence of a solvent and a catalyst to form a soluble poly(arylene ether) and an insoluble poly(arylene ether), separating the soluble poly(arylene ether) and the insoluble poly(arylene ether), and recycling the soluble poly(arylene ether). The process is particularly useful for synthesizing poly(arylene ether) copolymers in which the monomer compositions of soluble and insoluble copolymers may vary.
摘要:
A method of precipitating a poly(arylene ether) includes combining a poly(arylene ether) solution with an antisolvent at a shear rate of greater than 50,000 sec−1. The high shear mixing conditions produce a poly(arylene ether) dispersion in which the poly(arylene ether) solid contains reduced amounts of undesirably fine particles.
摘要:
A method of preparing a poly(arylene ether) includes oxidatively polymerizing a monohydric phenol in solution, concentrating the solution by removing a portion of the solvent to form a concentrated solution having a cloud point, Tcloud, and combining the concentrated solution with an anti-solvent to precipitate the poly (arylene ether), wherein the concentrated solution has a temperature of at least about (Tcloud−10° C.) immediately before it is combined with the anti-solvent. The method reduces the formation of undesirably fine particles in the product poly(arylene ether).
摘要:
A poly(arylene ether) produced by combining a poly(arylene ether) solution with an antisolvent at a shear rate of greater than 50,000 sec−1. The high shear mixing conditions produce a poly(arylene ether) dispersion in which the poly(arylene ether) solid contains reduced amounts of undesirably fine particles.
摘要:
A curable composition includes an olefinically unsaturated monomer and a poly(arylene ether) having two polymerizable groups and an intrinsic viscosity of about 0.05 to about 0.30 deciliters per gram. The composition exhibits an improved combination of high flow during molding and high post-cure stiffness and impact strength. The composition is particularly useful for fabricating plastic-packaged electronic devices.
摘要:
A method of preparing a poly(arylene ether) includes oxidatively polymerizing a monohydric phenol in solution, concentrating the solution by removing a portion of the solvent to form a concentrated solution having a cloud point, Tcloud, adjusting the temperature of the concentrated solution to at least about (Tcloud−10° C.), and combining the concentrated solution with an anti-solvent to precipitate the poly (arylene ether). The method reduces the formation of undesirably fine particles in the product poly(arylene ether).
摘要:
A method of preparing a poly(arylene ether) includes oxidatively coupling a monohydric phenol in a reaction solution at a reaction temperature that exceeds the cloud point temperature of the reaction solution. The oxidative coupling occurs in the presence of a metal complex catalyst, and when the catalyst includes an amine ligand, the method facilitates incorporation of the amine ligand into the poly(arylene ether) resin. The amine-incorporated poly(arylene ether) resins prepared by the method are useful in the preparation of higher molecular weight poly(arylene ether) resins and compatibilized blends of poly(arylene ether) resins with other thermoplastics.