摘要:
New compositions, useful as viscosity additives, having dispersing properties in various hydrocarbon oils, are disclosed, which comprise:recurrent units derived from one or more acrylic or methacrylic esters (e.g. 55-99.8% by weight),recurrent units derived from one or more nitrogenous vinyl monomers obtained by reacting triallylcyanurate with aliphatic amines or polyamines (e.g. 0.2-10% by weight), and optionallyrecurrent units derived from one or more vinyl aromatic monomers (e.g. 0-35% by weight).These copolymer compositions generally have a weight average molecular weight from 30,000 to 800,000 and a polydispersity generally lower than 5. They can be prepared by any radical copolymerization process using for example azoic or peroxydic initiators.The copolymer compositions considered are used as additives for improving the rheological properties of hydrocarbon oils. In addition, they exhibit good dispersing properties.
摘要:
New compositions, useful as viscosity additives, having dispersing properties in various hydrocarbon oils, are disclosed, which comprise:recurrent units derived from one or more acrylic or methacrylic esters (e.g. 55-99.8% by weight),recurrent units derived from one or more nitrogenous vinyl monomers obtained by reacting triallylcyanurate with aliphatic amines or polyamines (e.g. 0.2-10% by weight), and optionallyrecurrent units derived from one or more vinyl aromatic monomers (e.g. 0-35% by weight).These copolymer compositions generally have a weight average molecular weight from 30,000 to 800,000 and a polydispersity generally lower than 5. They can be prepared by any radical copolymerization process using for example azoic or peroxydic initiators.The copolymer compositions considered are used as additives for improving the rheological properties of hydrocarbon oils. In addition, they exhibit good dispersing properties.
摘要:
New compositions, useful as viscosity additives, having dispersing properties in various hydrocarbon oils, are disclosed, which comprise:recurrent units derived from one or more acrylic or methacrylic esters (e.g. 55-99.8% by weight),recurrent units derived from one or more nitrogenous vinyl monomers obtained by reacting triallylcyanurate with aliphatic amines or polyamines (e.g. 0.2-10% by weight), and optionallyrecurrent units derived from one or more vinyl aromatic monomers (e.g. 0-35% by weight).These copolymer compositions generally have a weight average molecular weight from 30,000 to 800,000 and a polydispersity generally lower than 5. They can be prepared by any radical copolymerization process using for example azoic or peroxydic initiators.The copolymer compositions considered are used as additives for improving the rheological properties of hydrocarbon oils. in addition, they exhibit good dispersing properties.
摘要:
Process for transporting gas hydrates formed from a natural gas or from a condensate gas, consisting in using a dispersing additive, possibly coupled with a film-forming additive, in solution in a liquid hydrocarbon fraction, this liquid hydrocarbon fraction participating in the formation of an emulsion and/or of a suspension with the condensation water produced and the hydrates. The dispersing additive is recycled after the transportation of the hydrates in the pipe.
摘要:
The invention concerns a process for inhibiting or retarding hydrate formation, growth and/or agglomeration in a fluid comprising water and gases, by addition of a hydrosoluble copolymer which does not contain a heterocycle but contains at least one sulphonate group. The copolymer is generally introduced at a concentration of 0.05% to 5% by weight with respect to the quantity of water in the medium. The copolymer can also be mixed with an alcohol (monoalcohol or polyol). In this case, the proportions are generally 0.5% to 20% by weight of alcohol with respect to the water content, for 0.05% to 3% by weight of copolymer with respect to the quantity of water content of the medium.
摘要:
This invention relates to a process and device for destroying solid waste by pyrolysis, in which a column of such waste is upwardly traversed at least partially by a stream of hot gas blown in at the base of said column, wherein said stream of hot gas is generated by at least one plasma jet. The invention results in the destruction of non-burned residues and in the improved flow of the molten residues.
摘要:
Impregnated silica is manufactured by passing a substantially anhydrous solution of a polar organic compound in a non-polar organic diluent through a bed of substantially anhydrous silica particles, under a pressure of at least 200 bars so as to modify the adsorbent properties of the silica particles with the selective properties of the polar compound without impairing the silica particle adsorbing efficiency.
摘要:
A microwave polymerization system for dentistry utilizes specifically controlled microwave energy to cure polymer materials so as to produce dental prosthetics, such as dentures, bridges and crowns, that are made in an extra-oral setting such as a dental laboratory or dental office, and to create dental composites for fillings and veneers that are used in an intra-oral setting directly in the patient's mouth. Unlike the microwave energy delivered by commercial microwave ovens which is controlled by pulsing a maximum voltage pulse on and off at a given duty cycle, the system utilizes metered and controlled microwave energy that is preferably continuous and voltage controlled, and regulates the application of this microwave energy by use of various feedback and control mechanisms. The metered and controlled microwave energy enables a higher degree of conversion of monomers into polymer chains in the polymerization process, thereby enhancing the physical and biocompatibility characteristics of both dental prosthetics and dental composites made from polymers. In an extra-oral embodiment, gaseous pressure is applied to the resin matrix during the polymerization process to further enhance the polymerization process. In an intra-oral embodiment, the polymerization process can be accomplished with less overall energy and with composite-matrices that maximally absorb the microwave energy so as to reduce heating of adjacent tissue.
摘要:
Hydrosoluble copolymers made of hydrophilic monomers, e.g., acrylamide, and of silane or siloxane derivative-based hydrophobic monomers, e.g., a silane or or siloxane acrylate, is obtained by micellar or heterogeneous radical copolymerization, and such copolymers can be used as rheology control agents in, e.g., a well bore.