Abstract: A poly(aryl ether sulfone) of low polydispersity containing no detectable cyclic polymer byproduct was prepared by melt polymerization without catalyst, solvent, and base. The poly(aryl ether sulfone) can be used without further purification for the manufacture of articles. A melt composition for fabricating an article comprises the poly(aryl ether sulfone) and, optionally, one or more additives.

Abstract: Polyhexahydrotriazine (PHT) film layers are formed by a process comprising heating a first mixture comprising i) a solvent, ii) paraformaldehyde, and iii) a diamine monomer comprising two primary aromatic amine groups at a temperature of about 20° C. to less than 150° C. This heating step forms a stable polyhemiaminal (PHA) in solution, which can be cast on a surface of a substrate, thereby forming an initial film layer comprising the PHA. The initial film layer is heated at a temperature of 180° C. to about 280° C., thereby converting the PHA film layer to a PHT film layer. Young's moduli of about 8 GPA to about 14 GPA have been observed for the PHT film layers.

Abstract: A poly(aryl ether sulfone) of low polydispersity containing no detectable cyclic polymer byproduct was prepared by melt polymerization without catalyst, solvent, and base. The poly(aryl ether sulfone) can be used without further purification for the manufacture of articles. A melt composition for fabricating an article comprises the poly(aryl ether sulfone) and, optionally, one or more additives.

Abstract: Polyhexahydrotriazine (PHT) film layers are formed by a process comprising heating a first mixture comprising i) a solvent, ii) paraformaldehyde, and iii) a diamine monomer comprising two primary aromatic amine groups at a temperature of about 20° C. to less than 150° C. This heating step forms a stable polyhemiaminal (PHA) in solution, which can be cast on a surface of a substrate, thereby forming an initial film layer comprising the PHA. The initial film layer is heated at a temperature of 180° C. to about 280° C., thereby converting the PHA film layer to a PHT film layer. Young's moduli of about 8 GPA to about 14 GPA have been observed for the PHT film layers.

Abstract: A salt catalyst comprises an ionic complex of i) a nitrogen base comprising one or more guanidine and/or amidine functional groups, and ii) an oxoacid comprising one or more active acid groups, the active acid groups independently comprising a carbonyl group (C?O), sulfoxide group (S?O), and/or a phosphonyl group (P?O) bonded to one or more active hydroxy groups; wherein a ratio of moles of the active hydroxy groups to moles of the guanidine and/or amidine functional groups is greater than 0 and less than 2.0. The salt catalysts are capable of catalyzing ring opening polymerization of cyclic carbonyl compounds.

Abstract: A field-based similarity search system includes an input device which inputs a query molecule, and a processor which partitions a conformational space of the query molecule into a fragment graph including an acyclic graph including plural fragment nodes connected by rotatable bond edges, computes a property field on fragment pairs of fragments of the query molecule from the fragment graph, the property field including a local approximation of a property field of the query molecule, constructs a set of features of the fragment pairs based on the property field, the features including a set of local, rotationally invariant, and moment-based descriptors generated from all conformations of the fragment graph of the query molecule, and weights the descriptors according to importance as perceived from a training set of descriptors to generate a context-adapted descriptor-to-key mapping which maps the set of descriptors to a set of feature keys.

Abstract: A field-based similarity search system includes an input device which inputs a query molecule, and a processor which partitions a conformational space of the query molecule into a fragment graph including an acyclic graph including plural fragment nodes connected by rotatable bond edges, computes a property field on fragment pairs of fragments of the query molecule from the fragment graph, the property field including a local approximation of a property field of the query molecule, constructs a set of features of the fragment pairs based on the property field, the features including a set of local, rotationally invariant, and moment-based descriptors generated from all conformations of the fragment graph of the query molecule, and weights the descriptors according to importance as perceived from a training set of descriptors to generate a context-adapted descriptor-to-key mapping which maps the set of descriptors to a set of feature keys.

Abstract: A field-based similarity search system includes an input device which inputs a query molecule, and a processor which partitions a conformational space of the query molecule into a fragment graph including an acyclic graph including plural fragment nodes connected by rotatable bond edges, computes a property field on fragment pairs of fragments of the query molecule from the fragment graph, the property field including a local approximation of a property field of the query molecule, constructs a set of features of the fragment pairs based on the property field, the features including a set of local, rotationally invariant, and moment-based descriptors generated from all conformations of the fragment graph of the query molecule, and weights the descriptors according to importance as perceived from a training set of descriptors to generate a context-adapted descriptor-to-key mapping which maps the set of descriptors to a set of feature keys.

Abstract: A similarity search method includes generating a feature database which stores data pertaining to a candidate molecule, as executed by a processor of a computer, the database including a hash table having entries which are generated based on, a set of descriptors generated from conformations of fragment graphs of the candidate molecule, the fragment graphs including plural fragment nodes connected by rotatable bond edges, a specific conformation of the fragment node including a fragment of the candidate molecule, and two neighboring fragments connected by a rotatable bond at a specific dihedral angle including a fragment pair, and a context-adapted descriptor-to-key mapping which maps the set of descriptors to a set of feature keys including indices that label grid cells in discriminant space.

Abstract: A similarity search method includes generating a feature database which stores data pertaining to a candidate molecule, as executed by a processor of a computer, the database including a hash table having entries which are generated based on, a set of descriptors generated from conformations of fragment graphs of the candidate molecule, the fragment graphs including plural fragment nodes connected by rotatable bond edges, a specific conformation of the fragment node including a fragment of the candidate molecule, and two neighboring fragments connected by a rotatable bond at a specific dihedral angle including a fragment pair, and a context-adapted descriptor-to-key mapping which maps the set of descriptors to a set of feature keys including indices that label grid cells in discriminant space.

Abstract: A field-based similarity search system and method includes a database for storing at least one candidate molecule, an input device for inputting a query molecule, and a processor for identifying a candidate molecule which is similar to the query molecule based on a similarity of fragment pair features.

Abstract: A field-based similarity search system and method includes a database for storing at least one candidate molecule, an input device for inputting a query molecule, and a processor for identifying a candidate molecule which is similar to the query molecule based on a similarity of fragment pair features.

Abstract: A field-based similarity search system and method includes a database for storing at least one candidate molecule, an input device for inputting a query molecule, and a processor for identifying a candidate molecule which is similar to the query molecule based on a similarity of fragment pair features.