Abstract:
An inorganic-organic composite comprises an inorganic phase, such as gypsum crystals, and a film forming organic phase. The film forming organic phase is selected from substituted starches having a degree of polymerization; degree of substitution and viscosity such that the substituted starches are insoluble in water during mixing but dissolve at a higher processing temperature during forming, setting or drying of the composite. Thus, excessive migration of the substitute starch is prevented and the composite is substantially strengthened.
Abstract:
Workstation, apparatuses and methods for the high-throughput synthesis, screening and/or characterization of combinatorial libraries. The invention relates to an array, which permits various high-throughput methods for synthesis, screening and/or characterization in the same array, without requiring sample transfer from the array. In a preferred embodiment, the synthesis, screening, and/or characterization steps are carried out in a highly parallel fashion, where more than one compound is synthesized, screened, and/or characterized at the same time. The invention may be practiced at the microscale. The array may comprise thermal channels, for regulating the temperature of the wells in the array. The wells of the array may comprise a membrane, which is used in various screening and characterization methods. The invention also relates to a covered array, comprising the array and an array cover, as well as an apparatus comprising the array, which comprises the array, an array cover and a stage. The array, array cover, and the stage may be modified as required for a variety of synthesis and/or analysis techniques. The array is easily interchangeable between different analytical instruments, and in an embodiment, the invention relates to an automated workstation, where the array is transferred between different synthesis, screening, and characterization stations. The invention also relates to a variety of methods for synthesis, screening, and characterization, which are adapted for combinatorial chemistry. Any of the embodiments of the invention may be used either alone or taken in various combinations.
Abstract:
Novel compounds are provided which are useful as catalysts, particularly in the polymerization of addition polymerizable monomers such as olefinic or vinyl monomers. The compounds are complexes of a mid-transition metal coordinated to at least two ligands, at least one of which is an unsaturated nitrogenous ligand. Depending on ligand substitution, stereospecific catalysts can be provided, including isospecific catalysts and syndiospecific catalysts. Catalyst systems containing the novel compounds in combination with a catalyst activator are provided as well, as are methods of using the novel compounds in the preparation of polyolefins. One embodiment of the present invention is a compound having the formula L1[MQ1Q2]L2 in which M is Nb, Ta, Mo, W, Mn or Re, Q1 and Q2 are each a univalent substituent, and L1 and L2 are ligands coordinated to M, wherein L1 contains a first coordinating nitrogen atom within a C═N group, and a second coordinating atom that is either a second nitrogen atom, optionally present in a second C═N group, or an oxygen, sulfur or phosphorus atom. The L2 group contains a coordinating atom that is either a second nitrogen atom, optionally within a C═N group, or a sulfur or phosphorus atom.
Abstract:
Unsaturated nitrogenous compounds are used as electron donors in conjunction with catalytic polymerization of addition polymerizable monomers such as olefins, using supported Ziegler-Natta catalysts. The electron donors may be used in the preparation of catalyst systems, thus serving as “internal” electron donors, or they may be added during or just prior to polymerization, as an “external” electron donor.
Abstract:
Construction materials containing surface modified reinforcements are used to fabricate composite structures. The composite structures comprise a matrix material and surface modified reinforcements, such as fibers and particulates. The surface modifier may be applied to a fiber surface using conventional sizing equipment and provides a durable film on the fiber. The surface modifier may be selected to have multifunctional properties, for example, increasing fiber pull-out strength, imparting bio-active properties, improving moisture resistance and other desirable properties to the composite structure.
Abstract:
Novel compounds are provided that are useful as catalysts, particularly in the polymerization of addition polymerizable monomers such as olefinic or vinyl monomers. The compounds are multinuclear complexes of transition metals coordinated to at least one unsaturated nitrogenous ligand. Catalyst systems containing the novel compounds in combination with a catalyst activator are provided as well, as are methods of using the novel compounds in the preparation of polyolefins.
Abstract:
A composite structure comprises an inorganic discrete phase, an organic matrix phase and an interfacial layer comprising both the inorganic and organic phases. In one process, the inorganic discrete phase is partially dissolved and the precipitated by a chemical reaction forming an interfacial layer having a finite thickness and transitioning from 100% inorganic to 100% organic.