Abstract:
A process for the production of ethylene copolymers containing hydroxyl groups which contain polymerized units of ethylene, an alkenol and if desired other monomers copolymerizable with ethylene, by copolymerization of a mixture of ethylene, alkenol and the other copolymerizable monomer(s), if any, at superatmospheric pressure and elevated temperature under the action of a free-radical polymerization initiator in the presence or absence of a polymerization regulator. 3-methyl-3-buten-1-ol is used as the alkenol. The process has the advantage that it is more easily carried out than comparable prior art methods and that it gives copolymers containing a relatively high proportion of polymerized units of alkenol.
Abstract:
A process for the continuous production of ethylene homopolymers by polymerization of ethylene by means of a polymerization initiator and a polymerization regulator at elevated temperature and superatmospheric pressure in a tubular reactor having two or three successive reaction zones, a mixture of ethylene, the polymerization initiator and the polymerization regulator being introduced continuously at the beginning of each reaction zone. It is characteristic of the process according to the invention that special conditions as regards temperature, pressure, polymerization initiator and polymerization regulator are maintained in the individual reaction zones.
Abstract:
PRODUCTION OF ETHYLENE HOMOPLYMERS BY POLYMERIZATION OF ETHYLENE UNDER THE ACTION OF ORGANIC HYDROPEROXIDES AND OXYGEN AS FREE-RADICAL-GENERATING POLYMERIZATION INTIATORS AND POLYMERIZATION MODIFIRES AT ELEVATED TEMPERATURE AND SUPERATMOSPHERIC PRESSURE IN A TUBULAR REACTOR HAVING TWO SUCCESSIVE REACTION ZONES, A MIXTURE OF ETHYLENE, POLYMERIZATION INITIATOR AND POLYMERIZATION MODIFIER BEING INTRODUCED CONTINUOUSLY AT THE BEGINNING OF EACH REACTION ZONE. SPECIFIC TEMPERATURE CONDITIONS, A HYDROPEROXIDE HAVING A SPECIFIC RELATIVELY HIGH HALF VALUE TEMPERATURE AND A POLYMERIZATION MODIFIER HAVING A SPECIFIC RELATIVELY HIGH CS-VALUE ARE USED IN THE FIRST REACTION ZONE, AND SPECIFIC TEMPERATURE CONDITIONS, OXYGEN AND A POLYMERIZATION MODIIRE HAVING A SPECIFIC RELATIVELY HIGH CS-VALUE ARE EMPLOYED IN THE SECOND ZONE. THE ETHYLENE HOMOPOLYMERS OBTAINED HAVE A NARROW MOLECULAR WEIGHT DISTRIBUTION AND ARE PRACTICALLY DEVOID OF VERY HIGH MOLECULAR WEIGHT CONSTITUENTS.
Abstract:
A METHOD OF AFTER-TREATING HIGH-PRESSURE POLYETHYLENE IN SHEARING UNIT, WHEREIN THE HIGH-PRESSURE POLYETHYLENE IS INTRODUCED INTO THE SHEARING UNIT AT 200* TO 300*C. AND A VISCOSITY OF 5X10**3 TO 1X10**5 POISES AND SUBJECTED TO A SHEARING GRADIENT, THE SHEARING SURFACES CONTACTING THE POLYETHYLENE MELT BEING HEATED A TEMPERATURE WHICH IS AT LEAST AS HIGH AS THAT OF THE POLYETHYLENE MELT AND THE POLYETHYLENE MELT BEING SHEARED AT SUCH A SHEARING SPEED THAT THE PRODUCT OF SHEARING SPEED AND RESIDENCE TIME IN THE SHEARING ZONE IS EQUAL TO 5X10**2 TO 5X10**4.
Abstract:
A PROCESS FOR POLYMERIZING ETHYLENE AT PRESSURES OF MORE THAN 1000 ATMOSPHERES AND AT TEMPERATURES OF FROM 150* TO 400*C. IN THE PRESENCE OF METHYL ISOBUTYL KETONE PEROXIDE. POLYETHYLENE HAVING A DENSITY OF FROM 0.924 TO 0.935 G/CCM. IS OBTAINED IN HIGHER YIELDS THAN IN CONVENTIONAL METHODS; IT IS USED FOR THE PRODUCTION OF TRANSPARENT FILM AND SHEETING.
Abstract:
A PROCESS FOR THE POLYMERIZATION OF PROPYLENE IN THE GAS PHASE IN A BED OF POWDERED POLYPROPYLENE BY MEANS OF A CATALYST SYSTEM OF: (A) A SOLUTION OF AN ALUMINUM ALKYL IN A HYDROCARBON; AND (B) A SUSPENSION OF A TITANIUM OR VANADIUM HALIDE COMPOUND IN A HYDROCARBON; IN WHICH THE TWO COMPONENTS (A) AND (B) ARE SUPPLIED SEPARATELY TO THE REACTION ZONE.
Abstract:
PRODUCTION OF EXPANDED MATERIAL BY MIXING COPOLYMERS OF ETHYLENE WITH POLYISOCYANATES AND EXPANDING AGENTS UNDER PRESSURE AND DECOMPRESSING THE HOMOGENEOUS MIXTURES.
Abstract:
A CONTINUOUS PROCESS FOR THE CHLORINATION OF RELATIVELY COARSE PARTICLED HIGH PRESSURE POLYETHYLENE AS A SUSPENSION OF 2-6 MM. PARTICLES IN A LIQUID CHLOROHYDROCARBON WITH WITHDRAWAL OF THE CHLORINATED POLYETHYLENE AS A SOLUTION IN THE CHLOROHYDROCARBON.
Abstract:
Film having improved transparency prepared from a mixture of an ethylene polymer and from 0.05 to 1.0 percent by weight (based on the mixture) of a copolymer of styrene, a graft copolymer of styrene, a homopolymer of propylene or a copolymer of propylene and ethylene; the film may be used as packaging material.