摘要:
A polymerization process includes contacting the following in a gas-phase reactor system under polymerization conditions for making a polymer product: a metallocene-based catalyst system including a supported constrained geometry catalyst, at least one monomer, and an additive selected from a group consisting of an aluminum distearate, an ethoxylated amine, and a mixture thereof. The additive may be selected from a group consisting of an aluminum distearate, an ethoxylated amine, polyethylenimines, and other additives suitable for use in the production of polymers for food contact applications and end products, including a mixture of a polysulfone copolymer, a polymeric polyamine, and oil-soluble sulfonic acid, in a carrier fluid, and mixtures thereof.
摘要:
A polymerization process includes contacting the following in a gas-phase reactor system under polymerization conditions for making a polymer product: a metallocene-based catalyst system including a supported constrained geometry catalyst, at least one monomer, and an additive selected from a group consisting of an aluminum distearate, an ethoxylated amine, and a mixture thereof. The additive may be selected from a group consisting of an aluminum distearate, an ethoxylated amine, polyethylenimines, and other additives suitable for use in the production of polymers for food contact applications and end products, including a mixture of a polysulfone copolymer, a polymeric polyamine, and oil-soluble sulfonic acid, in a carrier fluid, and mixtures thereof.
摘要:
The invention generally provides for methods for controlling polymer properties. In particular, invention provides for methods for controlling the comonomer composition distribution of polyolefins such as ethylene alpha-olefin copolymers by altering at least one or more of the following parameters: the molar ratio of hydrogen to ethylene, the molar ratio of comonomer to ethylene, the partial pressure of ethylene, and the reactor temperature without substantially changing the density and/or the melt index of the copolymer.
摘要:
A process for the production of an ethylene alpha-olefin copolymer is disclosed, the process including polymerizing ethylene and at least one alpha-olefin by contacting the ethylene and the at least one alpha-olefin with a metallocene catalyst in at least one gas phase reactor at a reactor pressure of from 0.7 to 70 bar and a reactor temperature of from 20° C. to 150° C. to form an ethylene alpha-olefin copolymer. The resulting ethylene alpha-olefin copolymer may have a density D of 0.927 g/cc or less, a melt index (I2) of from 0.1 to 100 dg/min, a MWD of from 1.5 to 5.0. The resulting ethylene alpha-olefin copolymer may also have a peak melting temperature Tmax second melt satisfying the following relation: Tmax second melt>D*398−245.
摘要:
A very low density polyethylene having a density of 0.890 to 0.915 and a Dart Drop value of at least about 450 g/mil or above is disclosed. Gas phase polymerization methods are also disclosed for making very low density linear polyolefins utilizing a metallocene catalyst, and the resulting polyolefin products. In a specific embodiment, a gas phase polymerization process is disclosed relating to the formation of a linear polyethylene having a very low density, e.g., ranging from 0.890 to 0.915, but with improved toughness.
摘要:
Tackifiers having Mn's of 5,000 or less and Tg's above 0.degree. C. are produced by combining a single site catalyst with an alpha-olefin and a cyclic monomer under conditions designed to produce low molecular weight.
摘要:
A process for the production of an ethylene alpha-olefin copolymer is disclosed, the process including polymerizing ethylene and at least one alpha-olefin by contacting the ethylene and the at least one alpha-olefin with a metallocene catalyst in at least one gas phase reactor at a reactor pressure of from 0.7 to 70 bar and a reactor temperature of from 20° C. to 150° C. to form an ethylene alpha-olefin copolymer. The resulting ethylene alpha-olefin copolymer may have a density D of 0.927 g/cc or less, a melt index (I2) of from 0.1 to 100 dg/min, a MWD of from 1.5 to 5.0. The resulting ethylene alpha-olefin copolymer may also have a peak melting temperature Tmax second melt satisfying the following relation: Tmax second melt>D*398−245.
摘要:
The present invention relates to a continuous gas phase process comprising polymerizing one or more hydrocarbon monomer(s) in a fluidized bed reactor in the presence of catalyst system or polymerization catalyst and a condensable fluid for a period of at least 12 hours where the bed temperature is less than the Critical Temperature and the dew point temperature of the gas composition in the reactor is within 25° C. of the bed temperature.
摘要:
A copoly(imidine-imide) consisting of a copolymer of polyimidines and polyimides having, in the basic chain structure of the polymer, imidine structures represented by formula (I) and the imide structures represented by formula (II): ##STR1##
摘要:
Ethylene alpha-olefin copolymers formed by contacting at least one supported metallocene catalyst, ethylene, and an alpha-olefin in a gas phase reactor are disclosed. In some embodiments, the polymer may have: a density of between 0.890 and 0.970 g/cc; a melt index of between 0.7 and 200 dg/min; a melt index ratio of less than 30; an ESCR value of greater than 1000 hours; and a 1% secant modulus of greater than 75,000 psi. In other embodiments, the polymer may have: a density of between 0.930 g/cc and 0.970 g/cc; a melt index of between 10 dg/min and 200 dg/min; a melt index ratio of between 10 and 25; a part weight of greater than 3 g and a part length of greater than 38 cm in a spiral flow test, and; a zero shear viscosity of less than 150 Pa·s. Processes to produce these polymers are also disclosed.