摘要:
Methods and compositions relate to a Fischer-Tropsch catalyst utilized to convert syngas into paraffins. The catalyst includes a given amount of sulfur content from contact of a catalytic supported metal with sulfur. Subsequent activation of the catalyst prepares the catalyst to be used for conversion of the syngas. The sulfur content maintained in the catalyst after being activated influences selectivity to paraffins over olefins and oxygenates.
摘要:
Methods and compositions relate to a Fischer-Tropsch catalyst utilized to convert syngas into paraffins. The catalyst includes a given amount of sulfur content from contact of a catalytic supported metal with sulfur. Subsequent activation of the catalyst prepares the catalyst to be used for conversion of the syngas. The sulfur content maintained in the catalyst after being activated influences selectivity to paraffins over olefins and oxygenates.
摘要:
A wet-etch composition for polyamic acids and partially cured polyamic acids comprising an aqueous solution having a major portion of water, a substituted hydrocarbon solvent and a non-ionic base that is strong enough to deprotonate the polyamic acid or a partially cured polyamic acid in a weight ratio of 0.1-49:49-0.1, with the proviso that the composition contains less than 1.0 percent ionic base. The present invention further provides a process for wet-etching polyamic acids or partially cured polyamic acids.
摘要:
Resinous condensation polymers of polycarboxylic acid compounds and aromatic diprimary amines comprising diamino-t-butyltoluene are described. In particular, film-forming polyamides, polyimides and polyamide-imides and their copolymers made using diamino-t-butyltoluene which have amino groups meta or para to each other on a benzene ring are described. These polymers have some solubility in organic solvents such as N-methylpyrrolidone, a high glass transition temperature, excellent thermal stability, and are useful in films, fibers and composites, and in the electronics industry as electrical component substrates, protective coatings, interlevel dielectrics and the like.
摘要:
Partially soluble, film-forming polyimides and their copolymers made using 3,5-diaminobenzotrifluoride are described. Thin films and coatings of these materials are relatively colorless and the polymers have a high Tg, excellent thermal stability, lower moisture uptake, and lower dielectric constant. They are useful as films, fibers, molded articles and as protective coatings, interlevel dielectrics, electric circuit substrates and the like for the electronics industry.
摘要:
Oxybisaniline is prepared in high yield by reacting a hydroxylamine with a polycarboxylic diphenyl ether in the presence of an inorganic acid. The acid groups are directly converted to amine groups. By-products of the reaction are negligible.
摘要:
A chemical resistant copolymer useful in electronic applications, said copolymer is a polyimide containing a 3,3',4,4'-tetracarboxybiphenyl dianhydride (BPDA) moiety, at least one other dianhydride moiety, and at least one diamine.
摘要:
Resinous condensation polymers of polycarboxylic acid compounds and aromatic diprimary amines comprising diamino-t-butylbenzens are described. In particular, film-forming polyamides, polyimides and polyamide-imides and their copolymers made using diamino-t-butylbenzenes which have amino groups meta or para to each other on a benzene ring are described. These polymers have some solubility in organic solvents such as N-methylpyrrolidone, a high glass transition temperature, excellent thermal stability, and are useful in films, fibers and composites, and in the electronics industry as electrical component substrates, protective coatings, interlevel dielectrics and the like.
摘要:
Compositions for forming polymeric layers useful in the manufacture printed wiring boards and other electrical interconnecting devices are disclosed. The compositions typically are processable in aqueous base and can be made photosensitive with the addition of a positive acting photosensitive compound. The compositions are particularly useful in the manufacture of laminable films used to make printed wiring boards. Multilayer printed wiring boards made using such films, and methods for making and using the films and boards, also are disclosed.