Abstract:
A Ziegler-Natta type catalyst having an improved hydrogen response provides for narrowing of the MWD of resulting polyolefins polymerized using such catalyst, with such catalyst generally made by a) contacting a soluble magnesium dialkoxide compound of the general formula Mg(OR″)2 with a halogenating agent capable of exchanging one halogen for one alkoxide to form a reaction product A, where R″ is a hydrocarbyl or substituted hydrocarbyl having from 1 to 20 carbon atoms; b) contacting reaction product A with a first halogenating/titanating agent to form reaction product B; and c) contacting reaction product B with a second halogenating/titanating agent to form a catalyst component; wherein in at least one of steps b) and c), the halogenating/titanating agent is a blend of Ti(OPr)4 and TiCl4. Catalyst components, catalysts, catalyst systems, polyolefin polymers, and methods of forming each are disclosed.
Abstract:
A thermotropic liquid crystalline polymer melt polymerized in the presence of a viscosity modifier that can help increase the “low shear” viscosity of the resulting composition is provided. The increased “low shear” viscosity can minimize drooling of the polymer composition during processing and also allow it to possess a greater melt strength, which facilitates its ability to be processed in a wide variety of applications without losing its physical integrity. Despite having a relatively high “low shear” viscosity, the present inventors have discovered that the viscosity modifier does not substantially increase the “high shear” melt viscosity of the polymer composition. In this regard, the ratio of the “low shear” viscosity to the melt viscosity is generally very high, such as within a range of from about 50 to about 1000.
Abstract:
A liquid crystalline polymer composition that contains a liquid crystalline polymer and an aromatic amide oligomer is provided. The oligomer can serve as a flow aid by altering intermolecular polymer chain interactions, thereby lowering the overall viscosity of the polymer matrix under shear. The oligomer is also not easily volatized or decomposed during compounding, molding, and/or use, which minimizes off-gassing and the formation of blisters that would otherwise impact the final mechanical properties of a part made from the polymer composition. While providing the benefits noted, the aromatic amide oligomer does not generally react with the polymer backbone of the liquid crystalline polymer to any appreciable extent so that the mechanical properties of the polymer are not adversely impacted.
Abstract:
An aromatic amide compound having the following general formula (I) is provided: wherein, X1 and X2 are independently C(O)HN or NHC(O); G1, G2 and G3 are independently hydrogen, C(O)HN-phenyl, or NHC(O)-phenyl, wherein at least one of G1, G2 and G3 is C(O)HN-phenyl or NHC(O)-phenyl; Q1, Q2, and Q3 are independently hydrogen, C(O)HN-phenyl, or NHC(O)-phenyl, wherein at least one of Q1, Q2, and Q3 is C(O)HN-phenyl or NHC(O)-phenyl; R5 is halo, haloalkyl, alkyl, alkenyl, aryl, heteroaryl, cycloalkyl, or heterocyclyl; and m is from 0 to 4.
Abstract:
A molded part having a predetermined shape is provided. The molded part may be formed by casting a liquid crystalline polymer composition into a mold cavity at a relatively low shear rate. Due to the use of a relatively low shear rate, the polymer composition does not generally undergo extensive shear orientation, which can allow the resulting part to be further processed using standard finishing techniques. The ability to use relatively low shear rates during casting is achieved in the present invention through the use of an aromatic amide oligomer. More particularly, the present inventors have discovered that the aromatic amide oligomer can serve as a flow aid by altering intermolecular polymer chain interactions, thereby lowering the overall viscosity of the polymer matrix to “ultralow” levels without having a significant impact on the mechanical properties.
Abstract:
A thermotropic liquid crystalline polymer melt polymerized in the presence of a viscosity modifier that can help increase the “low shear” viscosity of the resulting composition is provided. The increased “low shear” viscosity can minimize drooling of the polymer composition during processing and also allow it to possess a greater melt strength, which facilitates its ability to be processed in a wide variety of applications without losing its physical integrity. Despite having a relatively high “low shear” viscosity, the present inventors have discovered that the viscosity modifier does not substantially increase the “high shear” melt viscosity of the polymer composition. In this regard, the ratio of the “low shear” viscosity to the melt viscosity is generally very high, such as within a range of from about 50 to about 1000.
Abstract:
A polyethylene may be prepared using a mixture of a silica supported catalyst and a magnesium chloride supported catalyst. By changing the ratio of the two catalysts, the polyethylene produced may have a varying bulk density and shear response. The method allows for the tuning or targeting of properties to fit a specific application, such as a blow molding or vapor barrier film.
Abstract:
Disclosed is a process for making a Ziegler-Natta catalyst having controlled particle size and distribution. It comprises altering the precipitation of a catalyst component from a catalyst synthesis solution including a soluble magnesium containing catalyst precursor by controlling the concentration of either the soluble magnesium containing catalyst precursor, wherein the average particle size of the catalyst component is increased, and the particle size distribution increased, with a decreased concentration of the soluble magnesium containing catalyst precursor; or of the precipitating agent, wherein the average particle size of the catalyst component is increased, and the particle size distribution increased with an increased concentration of the precipitating agent. Use of the invention enables improved catalyst consistency regardless of production scale and customizing of catalyst morphology to desired polymer morphology. The novel catalyst components may be used to prepare polymers, and end-use articles therefrom, having desirable properties. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.
Abstract:
Chromium catalysts may be prepared using a process including contacting a chromium catalyst precursor with a treatment agent. This catalyst may be used for polymerization of a variety of monomers, particularly olefins, to form polymers for a wide variety of applications. The catalyst exhibits desirable activity rates and polymers produced therewith may exhibit improved melt flow, polydisperity values, and changes in shear thinning as compared to those prepared under similar conditions but using the same treatment agent as a cocatalyst instead.
Abstract:
A putter-type golf club head is provided having enhanced moment of inertia and alignment characteristics. The putter head includes a front body and a weight body. The weight body includes a central weight section extending rearwardly from the front body a prescribed distance to a rear weight section. The putter head is configured such that the rear weight section has a width less than the width of the front body and greater than a width of the central weight section. Thus, both the longitudinal and lateral moments of inertia are improved to offer greater forgiveness and increased accuracy during putts. The central weight section may include at least one and more preferably two elongated, high-density elements that are visible on a top surface of the sole between the front body and the rear weight section. The visibility of the elongated elements, with optional parallel markings on a top surface of the golf club head, also act as alignment aids to the golfer.