General Electric Company

Sabic Innovative Plastics IP B.v.

Peter Kennedy Davis

Slawomir Rubinsztajn

Ryan Christopher Mills

Hans Looij

Matthew Hal Littlejohn

Michael Joseph O'Brien

Eric James Pressman

Wendy Wen-Ling Lin

Ignacio Vic Fernandez

Hans-Peter Brack

Anthony Yu-Chung Ku

Dennis James Patrick Maria Willemse

Michael Dominic Schulte

Jorge A Garcia Agudo

Laurus Van Der Wekke

Gerardo Hidalgo Llinas

Brian Dominic Stephens

David Domingo Fuster

Eric Joseph Aho

Miguel Angel Salomon Cheliz

Gary C Buczkowski

Disclosed herein are methods of forming substantially crystalline, dense silicon carbide fibers from infusible polysilazane fibers by utilizing a single stage pyrolysis. The pyrolysis is performed using a continuous process in a single furnace with a constant atmospheric condition. Also disclosed are substantially crystalline, dense silicon carbide fibers formed by these methods.

Method to form silicon carbide fibers by single stage pyrolysis of polysilazane precursors

Methods of producing low-halogen-containing polysilazane resins, which are used to make silicon carbide fibers and ceramic coatings, provide processes for removing halogens, including chlorine, from precursor polysilazane resins.

Methods of preparing polysilazane resin with low halogen content

Disclosed herein are methods of curing silicon carbide precursor polymer fibers, such as polysilazanes, using moisture and free radical generators, such as peroxides. Also disclosed are methods of forming, curing, and using silicon carbide precursor polymers that contain alkenyl groups and free radical generators, such as peroxides.

Method for curing of green polysilazane-based silicon carbide precursor fibers

Polymer-based materials and processes suitable for producing panels, for example, panels for use in a fan shroud abradable seal of a turbofan engine. Such a process includes introducing constituents of an expandable foam material into a continuous forming apparatus that continuously compounds the constituents into a partially-cured compounded polymeric material, which is then continuously formed with the continuous forming apparatus to produce a continuous form having a constant cross-sectional shape transverse to a continuous forming direction of the continuous forming apparatus. A portion of the continuous form is then deformed to produce a preform, and the preform is cured within a restricted volume to cause the preform to expand and produce the panel.

Panels and processes therefor

The present disclosure generally provides methods and apparatus for efficiently crosslinking silicon carbide fiber precursor polymers with electron beam radiation. The methods and apparatus utilize a platform containing silicon carbide fiber precursor polymer. The temperature of the platform is regulated while the silicon carbide fiber precursor polymer is irradiated to thereby regulate the temperature of the irradiated silicon carbide fiber precursor polymer thereon. In this way, the temperature of the irradiated silicon carbide fiber precursor polymer is regulated via the platform both during and after it is subjected to radiation. At least one of the platform and the e-beam radiation mechanism may be translated with respect to the other to irradiate different portions of the silicon carbide fiber precursor polymer and, ultimately, the entirety of the silicon carbide fiber precursor polymer contained on the platform.

Methods and apparatus for crosslinking a silicon carbide fiber precursor polymer

The present disclosure generally relates to methods of using boron-containing additives for crosslinking polysilazane green fibers, which are precursors to silicon carbide fibers. These methods provide a controllable process for crosslinking silicon carbide fibers while providing a simple way for the introduction of boron as a sintering aid into the polymer structure.

Methods of using boron-containing additives as silicon carbide crosslinking agents

A method of forming polycarbonate includes the steps of introducing a plurality of reaction components to a reactor operating under melt polymerization conditions and removing ester-substituted phenol from the reactor. The plurality of reaction components include a dihydroxy compound, an ester-substituted diaryl carbonate, and a melt transesterification catalyst. The reaction components are introduced in a plurality of reaction component streams. A first reaction component streams includes a melt transesterification catalyst dissolved or suspended in a liquid carrier containing an ester-substituted phenol. The composition of the first reaction component stream is selected such that ester-substituted phenol is not generated as a reaction product in the first reaction component stream.

Method of forming polycarbonate

Polycarbonate is prepared by reactive extrusion on a reactive extruder. A method incorporates the steps of introducing a polycarbonate oligomer, an activated carbonate residue, and a transesterification catalyst to the extruder through a feed section. The extruder has the feed section, a polycarbonate exit section, and a reaction section between the feed section and the polycarbonate exit section. The reaction section is made up of at least one conveying section, kneading sections, and venting sections. The configuration of the reaction section requires that at least one venting section be disposed between each pair of kneading sections, and that the kneading sections and venting sections are selected such that the number of venting sections minus the number of kneading sections is greater than or equal to one. The method further contains the step of extruding the reaction components at a temperature in a range between 100&#xb0; C. and 500&#xb0; C., wherein during the extrusion of the reaction components, activated carbonate residue is removed through the venting sections.

Polycarbonates containing low levels of methyl salicylate prepared by a melt polymerization in a reactive extruder

Polycarbonate is prepared by reactive extrusion on a reactive extruder. A method incorporates the steps of introducing a polycarbonate oligomer, an activated carbonate, and a transesterification catalyst to the extruder through a feed section. The extruder has a feed section, a polycarbonate exit section, and a reaction section between the feed section and the polycarbonate exit section. The reaction section has one or more devolatilization units, wherein each devolatilization unit incorporates an array of vent-conveying sections and conveying sections arranged in a configuration of: (C V C)(V), and/or (V C V)(C). (V) is a vent-conveying section, (C) is a conveying section, x is 1 or more, and n is 1 or 0. The extruder screw in the vent-conveying sections and the conveying sections in each devolatilization unit have conveying elements or conveying elements and mixing elements and no elements that create a melt seal in the devolatilization unit. The method further includes the step of extruding the reaction components at a temperature in a range between 100&#xb0; C. and 500&#xb0; C., wherein during the extrusion of the reaction components, activated carbonate residue is removed through the vent-conveying sections.

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Niskayuna, NY, United States of America

Peter Kennedy Davis