摘要:
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.
摘要:
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.
摘要:
PROCESS FOR THE POLYMERIZAITON OF PROPYLENE IN THE GAS PHASE IN WHICH PROPYLENE IN LIQUID FORM IS INTRODUCED INTO A REACTION ZONE, VAPORIZED THEREIN AND POLYMERIZED WITH A CATALYST HAVING HIGH ACTIVITY.
摘要:
PRODUCTION OF GRANULAR PROPYLENE POLYMERS IN WHICH (1) PROPYLENE IS POLYMERIZED BY MEANS OF A ZIEGLER-NATTA CATALYST IN THE ABSENCE OF SOLVENTS OR DILUENTS SO THAT A POWDERED POLYMER IS DIRECTLY OBATINED WHICH HAS SPECIAL SPECIFICATION, (2) THIS POLYMER IS GIVEN A THERMAL AND MECHANICAL AFTERTREATMENT IN A SPECAIL WAY WITHOUT THE CATALYST HAVING BEEN PREVIOUSLY DEACTVATED, AND (3) THE POLYMER THUS AFTERTREATED IS HOMOGENIZED, EXTRUDED AND GRANLUATED BY CONVENTIONAL METHODS. THE POLYMER OBTAINES IS PARTICULARLY EASY TO PROCESS.
摘要:
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.
摘要:
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.
摘要:
SPECIAL SURFACES FOR PLAYING FIELDS COMPRISING AN UPPER LAYER, A1, A MIDDLE LAYER A2 AND A LOWER LAYER A3, LAYERS A1 AND A3 CONSISTING OF A THERMOPLASTIC MOLDING MATERIAL HAVING A SPECIAL COMPOSITION. THE LAYERS A1 AND A3 ARE WEBS OR BOARDS HAVING PARALLEL RIBS ON ONE SIDE, AND THE LAYER A2 IS A STRIP OR SHEET OF STEEL OR PLASTICS MATERIAL. THE RIBS ON THE LAYERS A1 AND A3 ARE IN CONTACT WITH THE MIDDLE LAYER A2 AND ARRANGED IN SUCH A WAY THAT THEY ARE STAGGERED AT EQUAL DISTANCES IN REALTION TO EACH OTHER.
摘要:
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.
摘要:
SPECIAL SURFACES FOR PLAYING FIELDS COMPRISING AN UPPER LAYER (A1) AND A LOWER (A2), EACH LAYER CONSISTING OF A THERMOPLASTIC MOLDING MATERIAL HAVING A SPECIAL COMPOSITION. THE LAYERS (A1) AND (A2) ARE WEBS OR BOARDS PROVIDED WITH APRALLEL RIBS ON ONE SIDE ONLY, LAYER (A1) BEING ARRANGED ON TOP OF LAYER (A2) IN SUCH A WAY THAT THE RIBBED SIDES ARE IN CONTACT, THE RIBS OF ONE LAYER BEING AT AN ANGLE OF FROM 45* TO 90 TO THOSE OF THE OTHER LAYER.