Patent application number | Description | Published |
20110144289 | Multi reactor process - This invention relates to the polymerization of ethylene polymers using a continuously stirred tank reactor (CSTR) that is connected in series to a tubular reactor. The tubular reactor receives a polymer solution from the CSTR. Further polymerization in the tubular reactor improves production efficiencies, particularly with respect to lowering the amount of energy required to recover the polymer and residual comonomer from the solution. The use of tempered i.e. (heated) ethylene in the tubular reactor has been discovered to mitigate gel problems and lower/reduce levels of hexane extractables. | 06-16-2011 |
20120101321 | Ethylene oligomerization - The oligomerization of ethylene using a chromium catalyst having a bridged diphosphine ligand can produce a selective product distribution (to predominantly hexene or predominantly octene/hexene) when activated with an aluminoxane. The oligomerization reaction also produces polymer by product—particularly when the aluminoxane is provided in a non-aromatic solvent. The present invention mitigates this problem. | 04-26-2012 |
20120142989 | HEAT MANAGEMENT IN ETHYLENE OLIGOMERIZATION - The oligomerization of ethylene using a chromium catalyst having a heteroatomic ligand may be used to provide oligomerization products that are selective towards hexene and/or octene. However, such processes also typically produce some polymer as an undesirable by product. The present invention is directed towards improvements in the selective oligomerization of ethylene. | 06-07-2012 |
20120149856 | CATALYST ACTIVATION IN A DUAL REACTOR PROCESS - Catalysts are activated in a dual reactor solution process by adding substoichiometric and superstoichiometric amounts of an ionic activator to an organometallic polymerization catalyst in a first and second reactor respectively. The new activation method allows one to alter process conditions in a favorably way with minimum impact to process economics. The new activation method also provides polymers which give films having improved optical properties. | 06-14-2012 |
20120271087 | Activation for Oligomerization - The oligomerization of ethylene using a chromium catalyst and an aluminoxane activator is well known. The undesired formation of polyethylene as a by-product is also known to occur during prior oligomerization processes. We have discovered that the use of an aluminoxane that is prepared by non-hydrolytic means provides a highly productive activator (co-catalyst) for ethylene oligomerization and mitigates the undesired formation of by-product polyethylene. | 10-25-2012 |
20140142360 | BULK ETHYLENE OLIGOMERIZATION USING A LOW CONCENTRATION OF CHROMIUM CATALYST AND THREE-PART ACTIVATOR - This invention enables the “bulk” oligomerization of ethylene (i.e. the oligomerization of ethylene in the presence of the oligomer product) using a catalyst system comprising 1) a very low concentration of a chromium catalyst and 2) a three part activator. The chromium catalyst contains a diphosphine ligand, preferably a so called P—N—P ligand. The activator includes an aluminoxane, trimethyl aluminum, and triethyl aluminum. | 05-22-2014 |
20150284303 | CONTINUOUS ETHYLENE TETRAMERIZATION PROCESS - A continuous flow process for the oligomerization of ethylene using a chromium catalyst having a phosphorus-nitrogen-phosphorus (“P—N—P”) ligand provides high selectivity to the desired tetramer (1-octene) with reduced production of coproduct C | 10-08-2015 |
20160083539 | SHRINK FILM FROM SINGLE SITE CATALYZED POLYETHYLENE - Shrink film having a desirable balance of properties is manufactured from a polyethylene blend composition having a fractional melt index and a molecular weight distribution of from about 2.5 to about 7. The blend composition comprises a first blend component that is made with a single site catalyst and has a molecular weight of greater than about 140,000 and a first density, d | 03-24-2016 |