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 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:
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.
Abstract:
PRODUCTION OF ETHYLENE HOMOPOLYMERS HAVING A SPECIFIC DENSITY BY POLYMERIZATION OF ETHYLENE UNDER THE ACTION OF ORGANIC PEROXIDES AND OXYGEN AS FREE-RADICAL-GENERATING POLYMERIZATION INITIATORS AND OF POLYMERIZATION MODIFIERS 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. OXYGEN AS POLYMERIZATION INITIATOR AND A MIXTURE OF A POLYMERIZATION MODIFIER HAVING A SPECIFIC RELATIVELY LOW C5 VALUE AND A POLYMERIZATION MODIFIER HAVING A SPECIFIC RELATIVELY HIGH C5 VALUE ARE USED IN THE FIRST REACTION ZONE, AND AN ORGANIC PEROZIDE HAVING A SPECIFIC HALF VALUE TEMPERATURE AS POLYMERIZATION INITIATOR AND A MIXTURE OF A POLYMERIZATION MODIFIER HAVING A SPECIFIC RELATIVELY LOW C5 VALUE AND A POLYMERIZATION MODIFIER HAVING A SPECIFIC RELATIVELY HIGH POLYMERIZATION MODIFIER HAVING A SPECIFIC RELATIVELY HIGH C5 VALUE ARE EMPLOYED IN THE SECOND REACTION ZONE. THE ETHYLENE HOMOPOLYMERS OBTAINED HAVE A WIDE MOLECULAR WEIGHT DISTRIBUTION AND ARE PRACTICALLY DEVOID OF VERY HIGH MOLECULAR WEIGHT CONSTITUENTS.
Abstract:
PRODUCTION OF ETHYLENE HOMOPOLYMERS HAVING A SPECIFIC DENSITY BY POLYMERIZATION OF ETHYLENE UDER THE ACTION OF ORGANIC PEROXIDES AND OXYGEN AS FREE-RADICAL-GENERATING POLYMERIZATION INITIATORS AND OF POLYMERIZATION MODIFIERS AT ELEVATED TEMPERATURE AND SUPERATOMSPHERIC PRESSURE IN A TUBULAR REACTOR HAVING TWO SUCCESSIVE REACTION ZONES, A MIXTURE OF ETHYLENE, POLYMERIZATION INITIATOR AND POLYMERIZATION MODIFIER BEING INTRODUCED CONTINOUSLY AT THE BEGINNING OF EACH REACTION ZONE. OXYGEN AS POLYMERIZATION INITATOR AND A POLYMERIZATION MODIFIER HAVING A SPECIFIC RELATIVELY LOW CS VALUE ARE USED IN THE FIRST REACTION ZONE, AND AN ORGANIC PEROXIDE AHVING A SPECIFIC HALF VALUE TEMPERATURE AS POLYMERIZATION INITIATOR AND A POLYMERIZATION MODIFIER HAVING A SPECIFIC RELATIVELY LOW CS VALUE ARE EMPLOYED IN THE SECOND REACTION ZONE. THE ETHYLENE HOMOPOLYMERS OBTAINED HAVE A WIDE MOLECULAR WEIGHT DISTRIBUTION AND ARE PRACTICALLY DEVOID OF VERY HIGH MOLECULAR WEIGHT CONSTITUENTS.
Abstract:
A PROCESS FOR THE PRODUCTION OF LOW MOLECULAR WEIGHT WAXY POLYTHYLENES BY POLYMERIZATION OF ETHYLENE AT ELEVATED TEMPERATURE AND SUPERATMOSPHERIC PRESSURE BY MEANS OF FREE-RADICAL INITIATORS. THE COURSE OF THE POLYMERIZATION IS INFLUENCED BY ADDING (A) HYDROGEN OR AN ALKANE AND (B) AND ALKENE.
Abstract:
A process for the manufacture of ethylene polymers by high pressure polymerization of ethylene, if desired mixed with other compounds copolymerizable with ethylene, and isolation of the reaction product in a multi-stage isolation zone. The molecular weight of the ethylene polymer can be varied by varying the mean product residence time in the isolation zone. The isolation zone preferably consists of two stages, with a higher pressure prevailing in the first stage than in the second stage.
Abstract:
O.Z. 0050/033573 of the disclosure: A process for the continuous production of an ethylene copolymer by compressing a mixture of ethylene and comonomer in a pre-compressor and a post-compresso, copolymerizing the mixture in a polymerization zone at a high temperature and high pressure, transferring the reaction mixture into a high pressure product isolation zone, from there into a low pressure product isolation zone and thereafter into a discharge extruder, and recycling the greater part of the unconverted monomer into the polymerization process and passing a small part of the unconverted gas into a low temperature isolation zone, in which process a small part of the gas recycled from the high pressure product isolation zone is passed into the low temperature isolation zone, which is preferably under a pressure of from 10 to 30 bar and at from -10 to -50.degree.C, and all the gas taken off the low pressure product isolation zone is fed to the pre-compressor. Using the novel process, the separating-off of the comonomer which has remained unconverted in the polymerization process can be improved.