A method for synthesizing a zirconium complex includes setting a temperature of a mixed solution at a certain temperature or more to synthesize a zirconium complex, the mixed solution being obtained by mixing: an organic solvent containing an organic substance having water miscibility; a chelating agent solution in which a chelating agent is dissolved; and zirconium dissolved in an acidic solution.

A method to form a phase change material (PCM). The method includes preparing a polymer solution by mixing an amount of a polymer in a solvent and mixing the polymer solution with an UiO-66 metal-organic framework (MOF) to form a composite. The polymer is a polyethylene glycol (PEG). The method further includes subjecting the composite to ultrasonic agitation and evaporating the solvent from the composite to form the PCM. After the evaporation of the solvent, particles of the PCM exhibit rounded octahedral structures.

The present invention relates to a novel Group 4 transition metal compound, a method for preparing the compound, a catalyst composition comprising the compound, and a method for preparing a polyolefin comprising performing a polymerization reaction of olefin monomers, in the presence of the catalyst composition. Since the Group 4 transition metal compound of the present invention exhibits an excellent catalytic activity in polyolefin synthesis reactions, as well as having excellent thermal stability, it can be used for polyolefin synthesis reactions at high temperatures, and by changing the type of a central metal and ligand, the weight average molecular weight of synthesized polyolefins and the octene content in the polymer can be controlled. Therefore, it can be effectively used in polyolefin synthesis processes in which grades are controlled.

The present invention relates to a novel Group 4 transition metal compound, a method for preparing the compound, a catalyst composition comprising the compound, and a method for preparing a polyolefin comprising performing a polymerization reaction of olefin monomers, in the presence of the catalyst composition. Since the Group 4 transition metal compound of the present invention exhibits an excellent catalytic activity in polyolefin synthesis reactions, as well as having excellent thermal stability, it can be used for polyolefin synthesis reactions at high temperatures, and by changing the type of a central metal and ligand, the weight average molecular weight of synthesized polyolefins and the octene content in the polymer can be controlled. Therefore, it can be effectively used in polyolefin synthesis processes in which grades are controlled.

Embodiments are directed to catalyst systems comprising at least one metal ligand complex and to processes for polyolefin polymerization incorporating the catalyst systems. The metal ligand complexes have the following structures: (I) ##STR00001##

Embodiments are directed to catalyst systems comprising at least one metal ligand complex and to processes for polyolefin polymerization incorporating the catalyst systems. The metal ligand complexes have the following structures: (I) ##STR00001##

Processes of polymerizing olefin monomers using catalyst systems and catalysts systems that include a procatalyst having a structure according to formula (I):

Processes of polymerizing olefin monomers using catalyst systems and catalysts systems that include a procatalyst having a structure according to formula (I):

Disclosed herein is a polycrystalline metal-organic framework membrane comprising a substrate material having a surface and a polycrystalline metal-organic framework attached to the surface of the substrate material, wherein the polycrystalline metal-organic framework is formed from a secondary building unit having the formula Ia or IIb and a ligand as defined in the application.

A heterogeneous material (e.g., a metal-organic framework or “MOF”) is useful for removing heavy metals from a liquid (e.g., water). The heterogeneous material may incorporate a group 16-containing heterocycle supported on solid media. Thiophene-containing MOFs, such as ATF-1 and DUT-67, may be used to remove lead from water. It is postulated that the metal is adsorbed via non-covalent interactions. The systems and methods described herein may also be applicable to other heavy metals. Thus, the applications are not limited to drinking water purification. Instead, the systems and methods may be used for a broad variety of other applications, such as nuclear waste remediation.