100results about How to "Improve polymerization" patented technology

This invention relates generally to low ethylene insertions into I-olefin polymers and processes for production of such polymers using unbridged fluxional metallocenes, primarily substituted aryl indenyl metallocenes, and more particularly to use of unbridged, fluxional, cyclopentadienyl or indenyl metallocene catalyst systems in methods of production of high melting point I-olefin homo- and co-polymers, particularly elastomeric crystalline and amorphous block homo- and co-polymers of I-olefins. The activity of fluxional unbridged metallocene polymerization catalysts containing at least one 2-arylindene ligand is increased 10x or more by the addition of small (typically 0.1-10 wt. %) amounts of ethylene to the polymerization system, which increase is termed the Polymerization Rate-Enhancement effect (PRE), which is measured in terms of an Ethylene Enhancement Factor (EEF) as a dimensionless ratio in the range of from about 1.1 to about 10 or above. The amount of ethylene included in the reaction system can be selected and controlled to be so small as to result in essentially minimal (<2 mole %) incorporation of ethylene units into the resulting elastomeric polymer and the molecular weight may be increased. Amounts of ethylene to generate the PRE effect may be greater than 0.1 wt. % and preferably range up to about 2 wt. %. However, if a polymer with more ethylene is desired, additional ethylene may be incorporated into the polymerization feed, including up to 10 to about 50 mole % based on olefin units. A second important aspect of this invention is the ability to use a PRE activity-enhancing amount of ethylene in an olefin polymerization without substantially affecting the physical properties of the elastomer. In a third important aspect of this invention, I-olefin elastomers are produced through incorporation of ethylene using unbridged fluxional catalyst systems which may not otherwise produce acceptable elastomeric homopolymers. This effect is termed the EPE effect, for Elastomeric Property-Enhancing effect. The EPE amount of ethylene required to produce such elastomers typically overlaps the PRE activity-enhancing amount. Incorporation of up to about 5 mole % or more of ethylene typically will produce an elastomeric polymer using such catalyst systems. Typical useful amounts of incorporated ethylene include about 1 to 3 mole %. Preferred polymers of this invention retain sufficient crystallinity to provide a high melting point (by DSC) of about 80° C., preferably above 100° C., including in the range of from about 120° C. to about 140° C. and above. Novel flexible alpha-olefin homo and copolymers having elongation in excess of 600% and substantially no retained force are disclosed.

The present invention relates in certain embodiments to methods, systems, and devices for treating vertebral compression fractures. In one embodiment, a bone cement injector is advanced into bone and injects a bone cement flow through the injector and a vapor flow from at least one vapor outlet in the injector. In another embodiment, the bone treatment system comprises an elongated member having a flow passageway, a bone fill material source, and a vapor source coupleable to the flow passageway. Still another embodiment describes a vapor injection device having an elongated member with a flow passageway, the elongated member configured for insertion into a bone and for delivering a bone fill material through the flow passageway, and having at least one vapor channel in communication with the flow passageway to deliver a vapor into the flow passageway to heat a bone fill material flow.

An apparatus (2) includes: a first tank (4); a line mixer (6); a second tank (8); a cooling jacket (10); a first tube (12); a second tube (14); and a third tube (16). In the first tank (4), (i) sodium persulfate serving as a polymerization initiator and (ii) water are fed so as to obtained an aqueous solution. The aqueous solution is continuously taken out and transferred via the first tube (12) to the line mixer (6). Between the first tank (4) and the line mixer (6), water is injected into the first tube (12). The water and the sodium persulfate aqueous solution are stirred together in the line mixer (6). This stirring decreases a concentration of the aqueous solution. The resulting aqueous solution is continuously fed to the second tank (8) via the second tube (14). The aqueous solution is then continuously taken out via the third tube (16) and is continuously added to an acrylic acid (salt) aqueous solution. This provides a production method which allows a high-quality water absorbing agent to be obtained with a compact apparatus.

The invention provides methods of producing composite polymers by combining fillers with polymers in the presence of pre-formed high molecular weight polymer. Monomer polymerization can be initiated through the addition of initiators or by reactive chemical groups on the surface of the fibers. The composite materials formed possess superior mechanical properties compared to similar polymer composites made by either purely mechanical mixing or solely polymerization of monomers in the presence of the fillers.

The invention provides methods and formulations involving the use of promoters that accelerate the polymerization of macrocyclic polyester oligomers (MPOs). For example, in certain embodiments, the invention provides blends of macrocyclic polyester oligomer (MPO), catalyst, and promoter that are substantially stable at ambient temperature for a period of time. The blend material may be stored without premature polymerization of MPO or deactivation of catalyst. The invention also provides processes employing one-part, ready-to-polymerize blends that contain MPO, catalyst, and promoter, as well as processes in which the catalyst and promoter are used in separate streams and are contacted when it is desired to accelerate polymerization of MPO. Methods of the invention offer advantages in the manufacture of thermoplastic parts and composites, due at least in part to the unique properties of MPO.

A liquid crystal display (“LCD”) panel includes a first substrate including a pixel electrode defining pixel areas, a first alignment layer disposed on the pixel electrode and a first reactive mesogen layer disposed on the first alignment layer, a second substrate including a common electrode layer disposed on an entire portion of the second substrate facing the first substrate, a second alignment layer disposed on the common electrode layer and a second reactive mesogen layer disposed on the second alignment layer, and a liquid crystal layer disposed between the first and second substrates and including a first liquid crystal compound represented by Chemical Formula 1, a second liquid crystal compound represented by Chemical Formula 2 and a third liquid crystal compound represented by Chemical Formula 3:

Subjects of the present invention are to provide resin particles having high ability and suitable for various purposes and to provide preparation method thereof.This invention provides resin particles each of which is formed by two curved surfaces or by one curved surface and one plane surface, has a boundary line between these two surfaces and satisfies the relationships:wherein D is particle diameter in horizontal direction and d is the maximum height in longitudinal direction in a side view in which the boundary line is placed in horizontal direction.