摘要:
Compounds having acidic protons and a molecular structure which can delocalize the electron density of the conjugate base (target compounds) are chlorinated by contacting such compounds with a perchloroalkane and aqueous base in the presence of a phase transfer catalyst which is an tetraalkylammonium hydroxide. Chlorinated products, preferably gem-dichloro compounds, are produced. The gem-dichloro compounds are useful for alkylation of aromatic compounds. For instance fluorene is chlorinated to form 9,9-dichlorofluorene which is reacted with such compounds as phenol or aniline to form such compounds as 9,9-bis(hydroxyphenyl)fluorene, 9,9-bis(aminophenyl)fluorene, or 9-aminophenyl-9-chlorofluorene.
摘要:
The invention is a process for producing a modified polytetrafluoroethylene which comprises polymerizing tetrafluoroethylene in an aqueous medium containing a dispersing agent with a polymerization initiator source and then, copolymerizing tetrafluoroethylene one or more fluorinated modifiers having an acid functional group or a functional group which is convertible to the acid group as a copolymerizable modifier in the presence of the resulting polytetrafluoroethylene to a polymerization point past the Kraft point to produce highly porous, fibrous, stratified fluoropolymers having cores made of homopolymer of poly-tetrafluoroethylene coated with sheath layers which are made of a copolymer of polytetrafluoroethylene and one or more modifiers.The invention also includes a highly porous, fibrous, stratified fluoropolymer having a plurality of interconnected, fibrous-like projections wherein the stratified fluoropolymer has a core layer of polytetrafluoroethylene substantially completely covered by a copolymer of polytetrafluoroethylene and a fluorocarbon modifier.
摘要:
A method of regenerating a deactivated fluorocarbonsulfonic acid polymer catalyst by contacting the deactivated catalyst with a solvent combination wherein a first solvent swells the structure of the polymer and the other acts as a diluent to modify the swelling action of the first. The combination dissolves the deactivating components.
摘要:
Preparation of dihydroxy-.alpha.-alkylstilbenes with reduced undesirable by-products can be achieved by carrying out dehydrohalogenation of a substantially uniform dispersion of a halogenated intermediate of the desired product in the presence of water and a polar protic solvent.
摘要:
Polyurethane articles of manufacture are treated so as to make their surfaces more adherent to paint by contacting the surfaces of the articles with a solution of phosphoric acid in a low molecular weight organic solvent, e.g. a carboxylic acid ester such as ethyl acetate. The treated article is then dried at an elevated temperature.
摘要:
This invention discloses improved heterogeneous acid catalysts and a method for preparing these catalysts. A heterogeneous acid catalyst has been prepared by coating a carrier with an aqueous emulsion containing a fluorocarbonsulfonic acid polymer in the sulfonyl fluoride form, removing the excess water, heating to a temperature above the softening point of the polymer for a time, and then converting the polymer to the active sulfonic acid form. The substrate has pores of about 0.1 micrometers or greater and a surface area of about 20 m.sup.2 /g or less.
摘要:
Superior solder flux, e.g., rosin flux, removal compositions are disclosed which have no flash point and are substantially non-corrosive toward aluminum. These compositions consist of about 0.5 to less than 2% methanol with about 3 to 10% of one or more alcohols containing 2-5 carbon atoms the balance being an inhibited 1,1,1-trichloroethane, wherein percentages are based on volume of the total composition.
摘要:
The invention is a process for the preparation of triaromatic bisphenols reacting a phenolic compound, e.g. phenol, with a suitable halo-compound, for instance 1,1-dichloroethylbenzene, 1-chlorostyrene, or mixtures thereof. The reaction may be conducted in the presence or absence of a solvent; an excess of the phenolic compound can serve as the solvent. The product is conveniently recovered by removing the by-product HCl, excess phenolic compound, excess solvent and cooling. Yields of bis-1,1-(4-hydroxyphenyl)-1-phenylethane which are greater than 90% of theoretical have been obtained by the reaction of phenol and 1,1-dichloroethylbenzene and a large portion of the yield is para isomer. Suitable halo-compounds include aromatic dihalo-compounds having at least one aliphatic substituent having two alpha-halogen atoms and at least one beta halogen atom, halo-styrenes having structures corresponding to such aromatic dihalo-compounds except that an alpha-halogen atom and a beta hydrogen atom are removed and there is a double bond between the alpha and beta carbon atoms, trihalotoluenes, and dihalocyanotoluenes.
摘要:
A method of purifying 3-chloro-2-hydroxypropyl trialkylammonium chloride. An aqueous slurry is prepared containing about 70-98 wt. % total solids including the chloride and impurities associated with the preparation thereof. To this slurry is then added a miscible alcohol having about 3-4 carbon atoms. A solid filtrate is collected and optionally washed with additional alcohol and dried. The solid filtrate is substantially more pure in the chloride than the starting material.
摘要:
An improved process of making an oxidation catalyst containing vanadium, tin, potassium and a silicate binder which comprises employing a porosity control agent and calcination conditions to produce a catalyst having a mean pore diameter in the range of 5-15.mu. and at least 90% of the pores having diameters