Abstract: A method for the removal of halogenated organic contaminants from particulate material by admixing an additive selected from the group consisting of a sodium salt and an ammonium salt with the particulate material, and passing a vapor phase of steam through the material to substantially remove the halogenated organic contaminant.

Abstract: Polychlorinated biphenyls and chlorinated hydrocarbons are separated from soil by oil assisted desorption followed by vacuum stripping in presence of a sweep gas.

Abstract: Polychlorinated biphenyl compounds are sorbed from aqueous solutions and mixtures by a variety of organic polymeric materials. The contaminant can be desorbed for further processing and destruction.

Abstract: Flame retardant blends of poly(aryloxysiloxane) and organic polymers such as polyethers, polyesters, polyetherimides and terpolymers of acrylonitrile-butadiene-styrene are provided. In many instances, the flame retardant blends exhibit improved chemical resistance, impact resistance and have an improved heat deflection temperature as compared to the original polymeric materials.

Abstract: Broad range blends of aromatic polycarbonate and poly(aryloxysiloxane), such as poly(silyloxytetraalkylbiphenyleneoxide), have been found to be transparent. These blends also have been found to be flame retardant and possess excellent mechanical properties, such as high Notched Izod Impact.

Abstract: Poly(silyloxytetraalkylbiphenyleneoxide)s are provided resulting from the reaction between a tetraalkylbiphenol, such as tetramethylbiphenol and an organosilicon material such as dimethyldichlorosilane or octamethylcyclotetrasilazane. The poly(silyloxytetraalkylbiphenyleneoxide)s are flame retardant film-forming materials useful as high performance injection moldable thermoplastic and dielectrics.

Abstract: Silicon-nitrogen compounds are prepared by the reaction of an olefinic amine such as allylamine with a polydiorganosiloxane such as 1,1,3,3-tetramethyldisiloxane, in the presence of a platinum-containing hydrosilation catalyst, preferably a specifically defined platinum complex of 1,3,5,7-tetravinyl-1,3,5,7-tetramethylcyclotetrasiloxane. Depending on the reaction conditions, the product may be any of several compounds including bis(aminoalkyl)polydiorganosiloxanes and alkenylaminodisiloxanes which are spontaneously converted to cyclic disiloxazanes. The cyclic disiloxazanes may in turn be converted by hydrolysis to bis(aminoalkyl)octaorganotetrasiloxanes.

Abstract: Silyl carbamates are prepared by reacting carbon dioxide with a silazane composition such as 2-methyl-2-sila-3-aza-5-hexene. The silyl carbamates may be converted to symmetrical bis(aminoalkyl)disiloxanes by hydrosilation followed by hydrolysis.

Abstract: Aromatic polycarboxylic acids and their anhydrides such as bisphenol A dianhydride are prepared from the corresponding polycarboximides, such as bisphenol A bisimide, by an exchange reaction with phthalic acid or phthalic anhydride and water in the presence of dimethyl-n-butylamine as an exchange catalyst. The use of this amine results in the formation of a product of decreased color, as compared with the use of triethylamine.

Abstract: Bis(aminoalkyl)disiloxanes such as 1,9-diamino-4,4,6,6-tetramethyl-5-oxa-4,6-disilanonane are prepared by contacting an acyclic olefinic silazane such as 2-methyl-2-sila-3-aza-5-hexene with a hydrosilation catalyst to form an intermediate which is then hydrolyzed. When certain olefinic silazanes are hydrosilated with a reaction product of a platinum compound with an olefinic siloxane, the intermediate is a composition comprising novel cyclic silazanes such as 1,1-dimethyl-1-sila-2-azacyclopentane.

Abstract: Phthalimides and the like in which the substituent on the imide nitrogen is a highly electron-deficient group may be prepared by the reaction of the appropriate amine with phthalic anhydride. These imides are useful for the preparation of polyimides by reaction with diamines.

Abstract: Olefinic silazanes are prepared by the reaction of an olefinic amine such as allylamine with a silazane such as dimethylaminodimethylsilane or tetramethyldisilazane, preferably in the presence of a catalytic amount of a hydrogen halide source such as dimethylchlorosilane as catalyst. The highly volatile amino compound generated as a by-product (e.g., ammonia or dimethylamine) is lost by volatilization and this furnishes at least part of the driving force for the reaction.

Abstract: A method is described for dehydrochlorinating 1,1,1-trichloro-2,2-bis(4-hydroxyphenyl)ethane employing a refluxing dipolar aprotic solvent, such as dimethylformamide, containing a lithium halide catalyst to produce a crystalline product consisting essentially of 1,1-dichloro-2,2-bis(4-hydroxyphenyl)ethylene. The crystalline product can be isolated in substantially pure form and converted to a high impact, flame retardant polycarbonate.

Abstract: A method of recovering aromatic bis(N-alkylimide)s from aqueous aromatic polyimide-alkyl amine aminolysis mixtures is provided by heating the aromatic polyimide in the presence of water and alkyl amine. The resulting aromatic bis(N-alkylimide)s can be converted to aromatic dianhydride by aromatic bisimide-organic amine exchange reactions.

Abstract: A method is provided for making aromatic bis(ether phthalic anhydride)s by effecting an imide-anhydride exchange between aromatic bis(ether N-organophthalimide) and phthalic anhydride in the presence of an imide anhydride exchange catalyst and water and extracting the aqueous imide-anhydride exchange reaction mixture with an inert organic solvent. Imide-anhydride exchange product having at least 97 mole percent aromatic bis(ether phthalic anhydride) can be made at substantially reduced temperatures and pressures, by increasing by a factor of at least two, the number of times the imide-anhydride exchange mixture is extracted.

Abstract: A method is provided for converting aromatic bis(ether N-organo substituted phthalimides) to aromatic bis(ether anhydrides) by heating a bisphasic aqueous-organic mixture of aromatic bis(ether N-organo substituted phthalimide), phthalic anhydride and an exchange catalyst to effect an imide-anhydride exchange producing an aqueous phase containing aromatic bis 4ether phthalic acid) and an organic phase containing N-organo substituted phthalimide. The aromatic bis(ether phthalic acid) is then optionally dehydrated to the corresponding anhydride.

Abstract: A method is provided for making aromatic bis(ether phthalic anhydride), for example, 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride by effecting an exchange reaction between molten aromatic bis(ether-imide) and phthalic anhydride in the presence of water and an imide-anhydride exchange catalyst. An enchanced rate of aromatic bis(ether phthalic anhydride) production has been found to occur, if the molten aromatic bis(ether imide) is contacted with the phthalic anhydride in the form of an aqueous feed mixture of phthalic acid and exchange catalyst and the resulting equilibrated mixture extracted with organic solvent.

Abstract: A method is provided for continuously converting aromatic bis(ether N-organo substituted phthalimides) to aromatic bis (ether anhydrides) by heating a biphasic aqueous-organic mixture of aromatic bis(ether N-organo substituted phthalimide), phthalic acid and an exchange catalyst in a heated coiled tube reactor to produce an aqueous phase containing aromatic bis (ether phthalic acid) and an organic phase containing N-organo substituted phthalimide which can then be separated and aromatic bis(ether phthalic anhydride) recovered from the aqueous phase.

Abstract: A method is provided for controlling the build-up in concentration of triorganoamine exchange catalyst in an organic extraction solvent used in the extraction of aromatic bis(ether phthalimide) and N-organo substituted phthalimide from an imide-anhydride exchange reaction mixture. The concentration of the triorganoamine exchange catalyst is controlled in the extracting organic solvent by extracting the organic solvent with an aqueous mixture of phthalic acid and triorganoamine and thereafter recycling the organic solvent to the extractor.

Abstract: Sets of certain halogenated aromatic organic compounds, for example, N-alkyl tetrahalophthalimides, have been found useful as chemical tags when employed in a thermal particulating organic resin. Improved tagging performance has been achieved over extended use periods at temperatures up to 140.degree. C., if the tags are microencapsulated prior to incorporation into the particulating organic resin.