The present disclosure relates to Lewis base catalysts. Catalysts, catalyst systems, and processes of the present disclosure can provide high temperature ethylene polymerization, propylene polymerization, or copolymerization. In at least one embodiment, the catalyst compounds belong to a family of compounds comprising amido-phenolate-heterocyclic ligands coordinated to group 4 transition metals. The tridendate ligand may include a central neutral hetrocyclic donor group, an anionic phenolate donor, and an anionic amido donor. In some embodiments, the present disclosure provides a catalyst system comprising an activator and a catalyst of the present disclosure. In some embodiments, the present disclosure provides a polymerization process comprising a) contacting one or more olefin monomers with a catalyst system comprising: i) an activator and ii) a catalyst of the present disclosure.

Embodiments of the present application are directed to procatalysts, and catalyst systems including procatalysts, including a metal-ligand complex having the structure of formula (I):

##STR00001##

The present disclosure relates to a perovskite that includes ABX.sub.3, where A is an organic cation, B is a second cation, X is an anion, and the perovskite has a film density (ρ) of less than 4.37 g/cm.sup.3. In some embodiments of the present disclosure, the film density may be in the range, 4.1 g/cm.sup.3≤ρ≤4.37 g/cm.sup.3. In some embodiments of the present disclosure, the organic cation may include at least one of dimethylammonium (DMA), guanidinium (GA), and/or acetamidinium (Ac). In some embodiments of the present disclosure, A may further include cesium.

A preparation method of bimetallic catalysts based on anthracene frameworks and use thereof in olefin polymerization is reported. Anthrecene frameworks were introduced, heat resistance of the catalysts is improved, and by changing central metals and configurations of the frameworks, steric and electronic effects of the metal catalysts of this model can be adjusted and controlled conveniently, and polyolefin polymer materials of different structures and different properties can be prepared, the bimetallic catalyst can be used in ethylene homopolymerization for preparation of high density polyethylene, ethylene/1-octene copolymerization for preparation of polyolefin elastomers and ethylene/norbornene copolymerization for preparation of cycloolefin copolymers. The bimetallic catalyst based on anthracene frameworks can be used in olefin high temperature solution polymerization for preparing polyolefin elastomers and cycloolefin copolymers, the polyolefin elastomers obtained have molecular weights as high as M.sub.W=890 kg.Math.mol.sup.−1, and the cycloolefin copolymers have copolymerization monomer insertion rates as high as 45 mol %.

The invention relates to a solid catalyst system comprising a chromium compound, a metal compound, an aluminium compound and a silicon oxide support, wherein the silicon oxide support has an average particle diameter in the range between ≥20 and ≤50 μm, a pore volume in the range between ≥1.7 ml/g and ≤3 ml/g, and a surface area in the range between ≥400 m.sup.2/g and ≤800 m.sup.2/g, and wherein the aluminium alkoxide compound has the formula
R.sub.1—Al—OR.sub.2
wherein R.sub.1 is selected from (C.sub.1-C.sub.8) alkyl groups and OR.sub.2 is selected from (C.sub.1-C.sub.8) alkoxyl groups.

This disclosure is generally directed to polymerization catalysts derived from 1,5-diazabicyclooctanes, catalyst systems utilizing such catalysts, and processes to polymerize alpha olefins therewith.

An ethylenically unsaturated and (co)polymerizable metal salt soluble in an ethylenically unsaturated reactive diluent is based on zirconium or on lanthanum and on an ethylenically unsaturated hemi-ester of a dicarboxylic acid. A process for the preparation of the salt and a crosslinkable composition comprising it are also disclosed. Uses of the metal salt include optical and dental uses, uses in composite materials, in moulding compositions, in 3D printing compositions and compositions for 3D articles and for coatings or adhesives. The finished crosslinked product which results from crosslinking the crosslinkable composition comprising the metal salt is also described.

Catalyst systems that include a chain transfer agent and a metal-ligand complex according to formula (I).

##STR00001##

A feedstock material for use in an additive manufacturing apparatus is prepared from a first material and a metal organic framework (MOF). The MOF comprises a plurality of nodes and a plurality of linkers, the plurality of linkers coupled to the plurality of nodes, thereby forming a framework. The MOF has a lower coefficient of thermal expansion than a coefficient of thermal expansion for the first material. As a result, the feedstock material has a reduced coefficient of thermal expansion as compared to the first material alone and thus exhibits low thermal expansion as its temperature is increased. The coefficient of thermal expansion for the MOF may be modified by using a different plurality of nodes and/or a different plurality of linkers, as well as by incorporating guest molecules or atoms into the framework of the MOF.

Metal halide perovskite crystals, composite materials that include metal halide perovskite crystals and a polymeric matrix material, devices that include metal halide perovskite crystals, and methods of forming metal halide perovskite crystals, composite materials, and devices. The devices may include optoelectronic devices, such as light-emitting diodes. The light-emitting diodes may emit red light.