摘要:
Olefin polymerization catalyst systems including a high molecular weight catalyst compound and a low molecular weight catalyst compound, and methods of making same are provided. High molecular weight catalysts include metallocene catalysts and low molecular weight catalysts include non-metallocene compounds including biphenyl phenol compounds. Generally catalyst systems may include less than about 5.0 mol % of the high molecular weight catalyst compound relative to said low molecular weight catalyst. Methods for olefin polymerization including the aforementioned catalyst systems, and polyolefins and products made therefrom.
摘要:
Provided is a method for making a polyolefin comprising contacting one or more olefins in a reactor containing a catalyst; polymerizing the one or more olefins to produce an olefin polymer characterized by a first melt flow ratio (MFR) and a first haze; and altering the reaction temperature in the reactor to shift the first MFR to a MFR that is different than the first MFR and to shift the first haze to a haze that is different than the first haze.
摘要:
The present invention discloses a fiber amplifier, a fabricating method thereof, and a fiber communication system. The fiber amplifier includes at least a pump laser, at least a gain medium and at least an integrated optical component. The integrated optical component includes multiple optical input/output ports, and the optical input/output ports are connected to the pump laser or gain medium directly or indirectly. The present invention may better address problems of unstable performance and difficulty in reducing the size of components in the prior art where fiber amplifiers are formed by a number of discrete components with many fiber fusion splices. In addition, the present invention may reduce the production complexity and costs of fiber amplifiers, and improve the productivity of fiber amplifiers.
摘要:
Bimodal polyethylene compositions and methods for making the same are provided. In at least one specific embodiment, the bimodal polyethylene composition can include a high molecular weight component having a weight average molecular weight (Mw) of from about 400,000 to about 950,000. The bimodal polyethylene composition can also include a low molecular weight component having a weight average molecular weight (Mw) of from about 3,000 to about 100,000. The high molecular weight component can be present in an amount ranging from about 25 wt % to about 40 wt % of the bimodal polyethylene composition. The bimodal polyethylene composition can also have a percent die swell of less than about 80%.
摘要:
The present invention discloses a fiber amplifier, a fabricating method thereof, and a fiber communication system. The fiber amplifier includes at least a pump laser, at least a gain medium and at least an integrated optical component. The integrated optical component includes multiple optical input/output ports, and the optical input/output ports are connected to the pump laser or gain medium directly or indirectly. The present invention may better address problems of unstable performance and difficulty in reducing the size of components in the prior art where fiber amplifiers are formed by a number of discrete components with many fiber fusion splices. In addition, the present invention may reduce the production complexity and costs of fiber amplifiers, and improve the productivity of fiber amplifiers.
摘要:
A network switching method, device and system for mobile multimedia services are provided. The method includes: detecting signal strength of media stream data of a first network, and when the signal strength of the media stream data of the first network is smaller than a first preset value, receiving media stream data of a second network in parallel; and buffering the media stream data of the second network, decoding the buffered media stream data of the second network, and playing the decoded media stream data of the second network. The device includes a first communication module, a detecting module, a switching module, a second communication module, a processing module and a playing module. The system includes a first network, a second network and a terminal. Through the method, device and system, the time delay in the process of switching the serving network is reduced, and the service interruption caused by the network switching when the terminal performs multimedia services is prevented.
摘要:
Polyethylene compositions having improved properties are provided. In one aspect, a polyethylene composition having a long chain branching index (g′avg) of 0.5 to 0.9; a Melt Flow Rate (MFR) of greater than (49.011×MI(−0.4304)), where MI is Melt Index; and a weight average molecular weight to number average molecular weight (Mw/Mn) of less than or equal to 4.6 is provided.
摘要:
Bimodal polyethylene compositions and methods for making the same are provided. In at least one specific embodiment, the bimodal polyethylene composition can include a high molecular weight component having a weight average molecular weight (Mw) of from about 400,000 to about 950,000. The bimodal polyethylene composition can also include a low molecular weight component having a weight average molecular weight (Mw) of from about 3,000 to about 100,000. The high molecular weight component can be present in an amount ranging from about 25 wt % to about 40 wt % of the bimodal polyethylene composition. The bimodal polyethylene composition can also have a percent die swell of less than about 80%.
摘要:
A polymerization catalyst system and polymerization processes using the catalyst systems are disclosed. The polymerization catalyst systems may include a) a first catalyst compound, and b) a second catalyst compound, wherein the first catalyst compound includes an oxadiazole-containing compound. In some embodiments, the oxadiazole-containing compound has essentially no hydrogen response, thus allowing better and/or tailored control of product properties when producing polymers using the catalyst system.
摘要:
A process for polymerizing olefin(s) utilizing a cyclic bridged metallocene catalyst system to produce polymers with improved properties is provided. The catalyst system may include a cyclic bridged metallocene, LA(R′SiR′)LBZrQ2, activated by an activator, the activator comprising aluminoxane, a modified aluminoxane, or a mixture thereof, and supported by a support, where: LA and LB are independently an unsubstituted or a substituted cyclopentadienyl ligand bonded to Zr and defined by the formula (C5H4-dRd), where R is hydrogen, a hydrocarbyl substituent, a substituted hydrocarbyl substituent, or a heteroatom substituent, and where d is 0, 1, 2, 3 or 4; LA and LB are connected to one another with a cyclic silicon bridge, R′SiR′, where R′ are independently hydrocarbyl or substituted hydrocarbyl substituents that are connected with each other to form a silacycle ring; and each Q is a labile hydrocarbyl or a substituted hydrocarbyl ligand.