摘要:
A process is provided for making metallated and substituted alkynes from feedstocks which include alkadienes containing allenic unsaturation or such alkadienes in a mixture with alkynes having either internal or terminal unsaturation, such as a mixture of propadiene and propyne. This reaction involves an initial step in which the allenic hydrocarbon and any internal alkyne is isomerized and simultaneously the resultant terminal alkynes are metallated with an alkali metal. The reaction is carried out at relatively low temperatures in a suitable inert solvent such as diethylether. When metallation is complete the reaction mixture can be contacted directly with any suitable electrophile, such as a halo silane, for example, chlorotrimethylsilane, and the alkali metal on the terminal alkyne is replaced with the desired substituent. The products thus formed are useful as monomers for preparing polymers having a variety of properties, for example, as asymmetric membranes for gas separation.
摘要:
A process is provided for making metallated and substituted alkynes from feedstocks which include alkadienes containing allenic unsaturation or such alkadienes in a mixture with alkynes having either internal or terminal unsaturation, such as a mixture of propadiene and propyne. This reaction involves an initial step in which the allenic hydrocarbon and any internal alkyne is isomerized and simultaneously the resultant terminal alkynes are metallated with an alkali metal. The reaction is carried out at relatively low temperatures in a suitable inert solvent such as diethylether. When metallation is complete the reaction mixture can be contacted directly with any suitable electrophile, such as a halo silane, for example, chlorotrimethylsilane, and the alkali metal on the terminal alkyne is replaced with the desired substituent. The products thus formed are useful as monomers for preparing polymers having a variety of properties, for example, as asymmetric membranes for gas separation.
摘要:
Polymerizable monomeric compounds corresponding to the general formula ##STR1## wherein R is H or CH.sub.3, U designates a cyclic or acyclic ureido or thioureido group and L designates a selected linking structure. The linking structure L may contain one or more oxy (ether), amino, amido, or carbonyl groups provided that any carbonyl group (CO) present is not directly attached to U or to an ethylenic carbon atom nor is such ethylenic carbon atom directly attached to a nitrogen atom. Representative examples include compounds corresponding to the formulae: ##STR2##
摘要:
Benzyl dimethyl amine is subject to electrofluorination in anhydrous HF to produce perfluoro-N,N-dimethylcyclohexylmethylamine. The obtained perfluoro compound is emulsified with the aid of a nonionic surfactant to form a stable emulsion showing promising use for administration as a blood substitute.
摘要:
Improved wet adhesion properties of water-based paints and coating compositions are obtained by incorporating into the polymeric resin emulsion systems employed in the formulation of such paints or coating compositions a monomeric compound having a terminal ureido group at one end thereof and a vinyl terminal group at the opposite end. Such incorporated monomeric compounds correspond to the general formula ##STR1## wherein R is H or CH.sub.3, U designates a cyclic or acyclic ureido or thioureido group and L designates a selected linking structure. In the simplest of such monomeric compounds, L is --CH.sub.2 --, as specifically represented by allyl urea. In other representative compounds the linking group L may be a polymethylene group - (CH.sub.2).sub.n --or the chain may contain one or more oxy (ether), amino, amido or carbonyl groups, provided that any carbonyl group (CO) present is not directly attached to U or to an ethylenic carbon atom nor is such ethylenic carbon directly attached to a nitrogen atom. Among preferred monomeric compounds imparting such improved wet adhesion are: N-Beta-allylaminoethyl ethylene urea, allyloxy-N-B-(1-ethylene ureido) ethyl acetamide, and allyl ester of N-ethyl-B-(1-ethylene ureido)-N-methyl carbamate. The polymer resin in the emulsion is one formed from one or more ethylenically unsaturated monomer compounds, such as acrylates and methacrylates, vinyl esters, vinyl chloride, mono- or di-ethylenic hydrocarbons; or copolymers, interpolymers or blends of these.
摘要:
A novel apparatus and method for rapidly generating an electrical map of a chamber of a heart utilizes a catheter including a body having a proximal end and a distal end. The distal end has a distal tip and an array of non-contact electrodes having a proximal end and a distal end and at least one location sensor. Preferably, two location sensors are utilized. The first location sensor is preferably proximate to the catheter distal tip and the second location sensor is preferably proximate to the proximal end of the non-contact electrode array. The catheter distal end further preferably includes a contact electrode at its distal tip. Preferably, at least one and preferably both of the location sensors provide six degrees of location information. The location sensor is preferably an electromagnetic location sensor. The catheter is used for rapidly generating an electrical map of the heart within at least one cardiac cycle and preferably includes cardiac ablation and post-ablation validation.
摘要:
The invention relates to a method of eliminating or substantially reducing the amount of cyanide formed in a polynitroaromatic, e.g. dinitrotoluene process. The invention comprises removing the nitrophenolic material from the mononitroaromatic formed in a first stage nitration of toluene prior to feeding the mononitroaromatic to the subsequent nitration zones.
摘要:
This invention relates to the paint composition having a unique paint vehicle, the paint vehicle comprises a latex comprising copolymer resin particles having at least 25% vinyl acetate polymerized therein, and the polymerized resin particles containing from about 0.1-10% by weight of a diallylic urea compound therein for providing wet adhesion characteristics to the paint composition.
摘要:
Novel compounds of the general formula ##STR1## (m = 0 or 1; n = 2 or 3 and R = H or CH.sub.3) are produced by reacting a 2-aminoalkyl alkylene urea with an allyl ester of a carbonylic acid. Among the particular allyl esters disclosed as reactants are diallyl carbonate, allyl and methallyl chloroformate, diallyl and dimethallyl oxalate. The recovered allyl esters of the alkyleneureido amic acid compounds find particular use as functional comonomers for imparting wet adhesion properties to emulsion systems containing vinyl ester polymers used in paints and coating compositions.