Abstract: Wettable, oxygen and carbon dioxide permeable, optically clear contact lenses are made of a composition comprising styrene or a substituted styrene compound, an ethylenically polyunsaturated crosslinking compound and an ethylenically unsaturated silicone containing compound and an .alpha.,.beta.-unsaturated dicarboxylic acid anhydride compound.
Abstract: Semi-crystalline polymer having a narrow molecular weight distribution and having incorporated therein a non-crystalline mobilizing additive which increases the free volume of the polymer, with such a combination preventing embrittlement of the polymer during and subsequent to irradiation sterilization.
January 8, 1981
Date of Patent:
August 21, 1984
Becton Dickinson and Company
Joel Williams, Terry Dunn, Vivian Stannett
Abstract: A composition for lining the walls of reactors and other connected apparatus in contact with reactant mixtures and reaction products during the polymerization of vinyl compounds, which reduces or prevents polymer deposits or incrustations on the said walls, constituted by the product of the prolonged reaction at 75.degree. C. between a polyvinyl alcohol of medium degree of hydrolysis prepared by the controlled alkaline alcoholysis of an ester of a wide molecular weight distribution polyvinyl alcohol and a polycarboxylic oxyacid, in a weight ratio of beween 35:10 and 40:10, which is applicable by known means, preferably by spraying.
Abstract: Production of vinyl chloride polymer of high porosity by polymerizing vinyl chloride in aqueous suspension and injecting an effective surfactant at a monomer to polymer conversion within the range 15 to 65%. An effective surfactant is found to be one which lowers the interfacial tension between 1,2-dichloroethylene and water to .ltoreq.8 dynes cm.sup.-1.
Abstract: A process for producing additional useful products from the cotrimer reaction product formed by the reaction of a diolefin and a furfural which comprises pyrolyzing the polymeric residue of the reaction product to form additional quantities of diolefin, furfural and cotrimer product.
Abstract: In accordance with one embodiment of this invention, a chromium catalyst supported on an aluminum phosphate-containing base is used in conjunction with a boron component either as a part of the base or as a cocatalyst. The resulting catalyst is unique both in its favorable sensitivity to molecular weight control agents such as hydrogen and in its ability to produce a fundamentally different olefin polymer. In accordance with another embodiment of this invention, the chromium is supported on a phosphate base produced using a melt of the aluminum salt.
Abstract: In one embodiment of this invention, a chromium component is supported on a silica/aluminum orthophosphate combination and used with an organometal cocatalyst. In accordance with other embodiments of the invention, the silica/phosphate combination for a chromium catalyst support is produced by either impregnating a silica xerogel with aluminum phosphate or boron phosphate, precipitating aluminum phosphate in the presence of a silica hydrogel, or physically mixing silica and aluminum phosphate xerogels. The resulting catalysts are capable of producing high melt flow olefin polymers and exhibit high activity. The resulting polymers have many unusual and desirable characteristics, such as high density and good environmental stress crack resistance.
Abstract: A bath composition for cataphoretic electrocoating of conductive surfaces contains coating agents which have been rendered soluble or dispersible with acid, contain basic nitrogen groups and carry groups of the general formulae (1) and (11) ##STR1## and, optionally, also groups of the general formulae (III) and/or (IV) ##STR2## where R.sup.1 and R.sup.2 are each alkyl, hydroxyalkyl or alkoxyalkyl, R.sup.3 and R.sup.4 are each hydrogen or methyl, R.sup.5 and R.sup.6 are each hydrogen, alkyl or a divalent radical of a polymer molecule which is bonded to a phenol or phenol ether, n.sup.1 is 1, 2 or 3 and n.sup.2 is 1 or 2, and where the oxygen bonded to the phenyl radical is either in the form of the OH group or etherified.
June 15, 1982
Date of Patent:
April 24, 1984
Fritz E. Kempter, Eberhard Schupp, Gunther Sabelus
Abstract: A catalyst system suitable for olefin polymerization comprising a catalyst component made up of chromium on a phosphated alumina or low phosphorus aluminum phosphate base and optionally an organometal cocatalyst. The resulting catalyst is particularly sensitive to the effects of hydrogen as a molecular weight control agent, thus allowing the production of polymers of having a melt flow varying over a wide spectrum utilizing the same catalyst.
Abstract: In accordance with one embodiment of this invention, a zerovalent chromium compound is introduced onto an activated phosphate-containing support and utilized in conjunction with an organometal cocatalyst, such as a trialkylborane. In accordance with another embodiment of this invention, a phosphate-containing xerogel is formed by removing water from an aluminum phosphate-containing hydrogen by means of azeotropic distillation or washing with a volatile, water miscible organic compound, activated and thereafter zerovalent chromium is incorporated therewith. In other embodiments of this invention, a phosphate-containing support is formed by forming aluminum phosphate from an aluminum alkoxide or from a melt, or by phosphating silica or alumina, or by forming an aluminum phosphate/silica combination. A support thus formed is activated and a zerovalent chromium compound added.
Abstract: Aluminum orthophosphate is prepared by combining a source of phosphate ions with an aluminum salt to form a concentrated mass, combining with sufficient neutralizing agent to partially neutralize, and aging until gellation occurs. The resulting aluminum phosphate is particularly suited for use as a base for a chromium olefin polymerization catalyst.
Abstract: Aluminum orthophosphate is prepared by combining a source of orthophosphate ions with an aluminum salt to form a concentrated mass, gelling, and thereafter converting the resulting hydrogel to a xerogel by removing water. The resulting aluminum phosphate is particularly suited for use as a base for a chromium olefin polymerization catalyst.
Abstract: A supported vanadium catalyst comprising a vanadium compound on a phosphate-containing base. This catalyst in conjunction with an organoaluminum cocatalyst is capable of giving good activity and producing a polymer having broad molecular weight distribution. The catalyst system is sufficiently sensitive to hydrogen to allow broad leeway in controlling the molecular weight of the resulting polymers.
Abstract: A titanium hydrocarbyloxide is solubilized by reacting with a water soluble polyhydroxy organic compound and the resulting product then combined with a strong acid to form a water soluble titanium composition which is combined with an inorganic catalyst support such as silica. The resulting composition is ideally suited as a support for a chromium olefin polymerization catalyst. The procedure results in an inexpensive way of producing a catalyst capable of giving high melt flow polymer under slurry conditions.
Abstract: A substantially external surfactant-free vinyl polymer emulsion product is disclosed. The process includes a first stage of dispersing in water an amine or inorganic base neutralized saturated polymer. The saturated polymer is formed from a monomeric mixture of carboxylic acid or anhydride containing ethylenic unsaturation with optionally additional copolymerizable ethylenically unsaturated monomers. In a second stage, a monomeric mixture of vinyl monomers is added to the water dispersion and the resultant mixture polymerized so as to form the substantially external surfactant-free vinyl polymer emulsion product.
Abstract: Disclosed are polymer blends of bis(allyl carbonate) polymers with polymers of olefinically unsaturated monomers, and the precursor blends of bis(allyl carbonate) monomers with polymers of olefinically unsaturated monomers, and fabricable resins prepared therefrom. Also disclosed is a method of fabricating, e.g., molding, injection molding, extruding, and the like, the fabricable resins. The bis(allyl carbonate) polymer blend is taken to a fabricable state, i.e., a fusible pseudoplastic that does not lose liquid on fabrication, either by admixture or admixture and reaction. The fabricable resin is then fabricated, e.g., extruded, molded, or the like, and then polymerized to a hard polymer. Also disclosed are blends of bis(allyl carbonates), monomeric and polymeric, with polymers having olefinic unsaturation.
Abstract: Disclosed is a multiple-stage flash devolatilization process, and apparatus for use therein, for recovering volatiles from mass processable polymers, which enables optimally low pressures to be employed without the necessity for refrigeration to condense the volatiles recovered thereby, comprising separating the volatiles from the polymeric material by flashing in a first flash devolatilization zone to remove the majority of the volatiles and then flashing in at least one additional flash devolatilization zone maintained at a lower pressure, preferably as low as practically possible, to remove residual volatiles, and then recovering the volatiles for further use by feeding the volatiles recovered from the additional flash zones back into the stream of volatiles leaving the first flash zone, the higher pressure of which allows the combined free volatiles present therein to then be condensed in a conventional non-refrigeration cooling process.
Abstract: An ethylene-.alpha.-olefin copolymer composition comprising two ethylene-.alpha.-olefin copolymers which are different in density, intrinsic viscosity and the number of short chain branching per 1000 carbon atoms. Extrusion processed materials, injection molded materials and films obtained from said composition are excellent in strength.
Abstract: A silica hydrogel containing chromium is aged under conditions such that at least a portion of the aging is carried out at a pH within the range of 7 to 9. The resulting hydrogel is converted to a xerogel by treating with a volatile organic liquid. The desired pH can be obtained either by adding a basic material such as ammonia to the hydrogel prior to or during the aging process or by using a chromium component which inherently gives a higher pH and/or resists the natural tendency for the pH to decrease during aging. An example of such a chromium compound is chloropentammine chromium(III) chloride. The resulting catalyst on activation is particularly suitable for olefin polymerization under conditions where higher melt flow polymer is desired.
Abstract: A silica hydrogel is contacted with a hydroxy-containing organic compound which is not completely miscible with water but which is sufficiently miscible with water so as to remove water, and thereafter the organic compound is removed by heating in an inert atmosphere prior to activation by heating in air. The heating in the inert atmosphere allows utilizing preferred organic compounds such as C.sub.5 and C.sub.6 alcohols which are desirable from a commercial standpoint because of the easy separation for recycle. In a preferred embodiment, the hydrogel is aged at a pH of 7 to 9 by means of either adding a base or by utilizing a chromium component containing bound nitrogen.