Abstract: Porous infusible polymer (IP) parts are made by incorporating 0.2 to 10 volume percent organic fibers, preferably with short lengths, into the particulate IP, consolidating the mixture under pressure and optionally heating, and then “burning off” the fibers. After the fibers are burned off the resulting part has porosity in which the pores are elongated, usually retaining the shape of the organic fibers. When these parts are exposed to moisture (which they usually absorb) and then suddenly heated they tend not to blister from vaporization of the water. This makes them useful as parts for aircraft (jet) and other engines and other applications where sudden temperature increase may occur.

Abstract: Perfluoropolymer parts containing (reinforcing) fibers oriented parallel to the surface of the parts may be joined by frictional welding processes such as vibration welding and ultrasonic welding without disturbing the orientation of the fibers. The parts may be used directly or cut into other shapes. Such parts are useful where high temperature resistance and/or chemical resistance is desired along with good physical properties such as strength and/or toughness. These types of parts include gaskets and seal rings.

Abstract: Porous infusible polymer (IP) parts are made by incorporating 0.2 to 10 volume percent organic fibers, preferably with short lengths, into the particulate IP, consolidating the mixture under pressure and optionally heating, and then “burning off” the fibers. After the fibers are burned off the resulting part has porosity in which the pores are elongated, usually retaining the shape of the organic fibers. When these parts are exposed to moisture (which they usually absorb) and then suddenly heated they tend not to blister from vaporization of the water. This makes them useful as parts for aircraft (jet) and other engines and other applications where sudden temperature increase may occur.

Abstract: Porous infusible polymer (IP) parts are made by incorporating 0.2 to 10 volume percent organic fibers, preferably with short lengths, into the particulate IP, consolidating the mixture under pressure and optionally heating, and then “burning off” the fibers. After the fibers are burned off the resulting part has porosity in which the pores are elongated, usually retaining the shape of the organic fibers. When these parts are exposed to moisture (which they usually absorb) and then suddenly heated they tend not to blister from vaporization of the water. This makes them useful as parts for aircraft (jet) and other engines and other applications where sudden temperature increase may occur.

Abstract: A bushing-like part made from a fluoropolymer and circumferentially oriented continuous high tensile modulus fibers is useful as a part for pumps and compressors and other similar types of apparatus. These parts may be useful at high temperatures and/or very corrosive environments, often lengthen the time between required maintenance checks, and usually perform better than metal bushings under nonstandard operating conditions.

Abstract: A bushing made from a thermoplastic polymer and circumferentially-oriented continuous high tensile modulus fibers is useful as a part for pumps and compressors and other similar types of apparatus. These parts may be useful at high temperatures and/or in very corrosive environments, often lengthen the time between required maintenance checks, and usually perform better than metal bushings under nonstandard operating conditions.

Abstract: Perfluoropolymer parts containing (reinforcing) fibers oriented parallel to the surface of the parts may be joined by frictional welding processes such as vibration welding and ultrasonic welding without disturbing the orientation of the fibers. The parts may be used directly or cut into other shapes. Such parts are useful where high temperature resistance and/or chemical resistance is desired along with good physical properties such as strength and/or toughness. These types of parts include gaskets and seal rings.

Abstract: Porous infusible polymer (IP) parts are made by incorporating 0.2 to 10 volume percent organic fibers, preferably with short lengths, into the particulate IP, consolidating the mixture under pressure and optionally heating, and then “burning off” the fibers. After the fibers are burned off the resulting part has porosity in which the pores are elongated, usually retaining the shape of the organic fibers. When these parts are exposed to moisture (which they usually absorb) and then suddenly heated they tend not to blister from vaporization of the water. This makes them useful as parts for aircraft (jet) and other engines and other applications where sudden temperature increase may occur.

Abstract: Copolyimides from 1,4-bis(4-aminophenoxy)-2-phenylbenzene and m- or p-phenylene diamine with biphenyl dianhydride exhibit a high Tg and reduced melt viscosity.

Abstract: Low void composites with high Tg polyimide matrices are prepared from stoichiometrically unbalanced precursors.

Abstract: Melt-fusible copolyimides based on pyromellitic anhydride and two defined classes of aromatic diamines, at least one diamine of each class being incorporated into the polyimide, each diamine class being present in an amount of 10-90 mole percent of the total diamine content (100 mole percent), melt below about 400.degree. C. and can be fabricated into articles, or can be applied to either fibrous or nonfibrous substrates to make prepregs, tapes, etc., which then are shaped into final articles, such as printed circuit boards or aircraft panels.

Abstract: Melt-fusible polyimides based on pyromellitic dianhydride and at least one defined aromatic diamine are useful in making low-void composites and thermoplastic tapes, which can be fabricated into articles such as, for example, aircraft and autobody panels, printed circuit boards, etc. Some of these polyimides are melt-processible and can be fabricated by conventional procedures such as extrusion and injection molding.

Abstract: A process for preparing a symmetrical dinitrodiphenyl ether from o- or p-nitrochlorobenzene or o- or p-nitrofluorobenzene comprising using a polar organic solvent, a potassium salt of a fatty carboxylic acid containing 2 to 20 carbon atoms or a potassium salt of an aromatic carboxylic acid containing 7 to 12 carbon atoms as catalyst, and either sodium or potassium carbonate to react with the p-nitrochlorobenzene. The reaction is carried out at from 150.degree. to 210.degree. C. until the o- or p-nitrochlorobenzene or o- or p-nitrofluorobenzene reacts.

Abstract: Melt-fusible polyimides based on pyromellitic dianhydride and 2,2-bis[3,5-dichloro-4-(4-aminophenoxy)phenyl]propane, alone or in combination with other defined diamines, are useful in making low-void composites and thermoplastic tapes, which can be fabricated into articles such as, for example, aircraft and autobody panels, printed circuit boards, etc.