摘要:
A lubricant comprising a mixture of a perfluoropolyalkyl ether and a phosphazene is described. The lubricant is useful in thin-film magnetic recording disk applications, where very low static and dynamical coefficients of friction are desired and balling effects are minimized.
摘要:
Polymer foam bodies are made from phosphorus-containing thermoplastic random copolymers of a dialkyl (meth)acryloyloxyalkyl phosph(on)ate. Foam bodies made from these copolymers exhibit increased limiting oxygen indices and surprisingly have good properties. In certain embodiments, the phosphorus-containing thermoplastic copolymer is blended with one or more other polymers and formed into nanofoams.
摘要:
A concrete article comprised of concrete having therein a reinforcing polymer that has a surface comprised of a thermoplastic hydroxy-functionalized polyether or polyester. The concrete article is made by mixing concrete, water and a reinforcing polymer that has a surface comprised of a thermoplastic hydroxy-functionalized polyether or polyester and curing said concrete mixture forming the concrete article.
摘要:
A method for preparing a concrete article comprised of concrete having therein a reinforcing fiber, where at least about 50 percent of the reinforcing fibers are frayed only at an end or ends of the reinforcing fibers, may be made by mixing concrete, water and a reinforcing fiber for a sufficient time to fray the ends of at least 50 percent of the fibers and curing the mixture to form the concrete article. The fiber may be a reinforcing fiber comprised of at least two filaments bonded together and the filaments being comprised of a polymeric core and a polymeric sheath comprised of a fusing-fraying polymer, such that the reinforcing fiber, when mixed with inorganic particulates, frays predominately only at an end or ends of the fiber
摘要:
The present invention is a method of preparing a 4,6-bisarylazoresorcinol comprising reacting an aryldiazonium salt and resorcinol in the presence of a base and a reaction medium containing water and a water-miscible solvent at a temperature in the range of about -5.degree. C to about -60.degree. C. The present invention is also a method of preparing a 2-substituted 4,6-bisarylazoresorcinol comprising reacting an aryldiazonium salt with a 2-substituted resorcinol. The 4,6-bisarylazoresorcinol or 2-substituted 4,6-bisarylazoresorcinol can then be hydrogenated to a 4,6-diaminoresorcinol, which is a precursor to polybisbenzoxazoles (PBOs), polymers which are useful as insulators, solar arrays, and tear-resistant gloves.
摘要:
In one embodiment, a composition (10) to be mixed with a molten metal to make a metal matrix composite, the composition characterized by: a ceramic reinforcing filler (12), the ceramic reinforcing filler not being wettable by molten aluminum and/or not being chemically stable in molten aluminum, the ceramic reinforcing filler being coated with a ceramic material, the ceramic material being wettable by and chemically stable in molten aluminum. In a related embodiment, a composition (20) to make a porous preform to be infiltrated by molten metal to make a metal matrix composite, the composition characterized by: a ceramic reinforcing filler (23), the ceramic reinforcing filler not being wettable by molten aluminum, the ceramic reinforcing filler being coated with a ceramic material (22) and optionally with a metal (21) such as nickel, the ceramic material being wettable by molten aluminum. The ceramic material can be coated on the ceramic reinforcing filler by a vacuum deposition technique such as vacuum sputtering.
摘要:
Butadiene copolymers are brominated in solution using bromine as the brominating agent. The bromination is conducted in the presence of an excess of an aliphatic alcohol, relative to the amount of bromine that is used. The bromination proceeds rapidly at mild conditions, and is selective in that only aliphatic carbon-carbon double bonds are brominated, and unwanted bromination at tertiary carbon atoms is largely or completely avoided. The resulting brominated polymers are characterized in having very good thermal stability.
摘要:
A method for cyanoisoalkylating phenols or other hydroxy-substituted aryl compounds, which may have up to two substitutents ortho or para to the hydroxy moiety, comprising reacting a molar excess of phenol or aryl compound with a ketone in the presence of cyanide ion and hydroxide ion at an elevated temperature.Compounds, such as 4-(1-cyano-1-methylethyl)phenol, produced via this method are useful as chemical intermediates in the preparation of polyurethanes, epoxy resins and pharmaceutical and agricultural products.
摘要:
Polyhydroxy ethers containing spirobiinadanols are tough, soluble thermoplastics with high heat distortion temperatures relative to bisphenol A based materials. These materials could function as surface coating resins.
摘要:
Brominated styrene-butadiene copolymers are useful gas transport films. The gas transport films are made by brominating a starting styrene-butadiene copolymer, and then forming the brominated styrene-butadiene copolymer into a film. The film may contain a blend of the brominated styrene-butadiene copolymer with one or more other polymers. The films have excellent selectivities between certain pairs of gasses, and exhibit high gas transport rates for various gasses such as carbon dioxide and water vapor.