Abstract:
A method for making a composite polyamide membrane including the step of applying a polyfunctional amine monomer and polyfunctional acyl halide monomer to a surface of the porous support and interfacially polymerizing the monomers to form a thin film polyamide layer, wherein the method is characterized by: i) conducting the interfacial polymerization in the presence of an aromatic anhydride monomer include at least one sulfonyl halide functional group, or ii) applying the aromatic anhydride monomer to the thin film polyamide layer.
Abstract:
Polyisocyanate-based polymers are formed by curing a reaction mixture containing at least one polyisocyanate and at least one isocyanate-reactive compound having at least two isocyanate-reactive groups in the presence of a bismuth thiophosphoric acid diester salt.
Abstract:
A bis(aryl)acetal has the formula wherein Y1 and Y2 are each independently chloro, bromo, iodo, mesylate, tosylate, triflate, or Bx, provided that Y1 and Y2 are not both selected from chloro, bromo, and iodo; each occurrence of Bx is independently a boron-containing functional group bonded to Ar1 or Ar2 via a boron atom; Ar1 and Ar2 are each independently unsubstituted or substituted C6-18 arylene, or unsubstituted or substituted C3-18 heteroarylene; provided that Ar1 and Ar2 are not covalently linked to each other to form a ring structure that includes —Ar1—O—C—O—Ar2—; and R1 and R2 are each independently hydrogen, unsubstituted or substituted C1-18 linear or branched alkyl, unsubstituted or substituted C3-20 cycloalkyl, unsubstituted or substituted C6-18 aryl, or unsubstituted or substituted C3-20 heteroaryl. The bis(aryl)acetal is useful as a monomer for oligoacetal and polyacetal synthesis via Suzuki polycondensation.
Abstract:
A polycarbamate comprising having less than 5 wt % total of biuret, cyanuric acid, and polyallophanate; and has a Gardner level of equal or greater than 3 is provided. A coating comprising the polycarbamate is also provided.
Abstract:
Embodiments are directed to terphenyl ligands and metal complex formed therefrom, wherein the metal complexes are used as procatalyst in polyolefin polymerization and comprise the following structure:
Abstract:
A process to prepare polycarbamate comprising adding urea to a polyol in the presence of at least one catalyst selected from the group consisting of compounds having the following formula MmZn; wherein M is a divalent metal, and Z is an anionic functionality or a functionality capable of forming a covalent bond with M and wherein n times a valence number of Z equals X and m times two equals Y wherein the absolute value of X equals the absolute value of Y is provided. Also provided are a polycarbamate produced according to the process and a coating composition comprising the polycarbamate.
Abstract:
Arylclobutene-containing multi-functional monomers are useful in the preparation of arylcyclobutene-based polymer coatings. Compositions comprising one or more arylclobutene-containing multi-functional monomers and one or more oligomers comprising as polymerized units one or more arylcyclobutene monomer provide arylcyclobutene-based polymer coatings having reduced stress. Such compositions are useful in the manufacture of electronic devices.
Abstract:
Provided is a non-cyclopentadienyl-based chromium-ligand complex, preferably a chromium-ligand complex of formula (J): LCr(RA)m(D)k (J), wherein L is a non-Cp monoanionic ligand; Cr (chromium) is in a formal oxidation state of +3 or +2; when Cr formally is Cr+3, either m is 1 and RA is hydrocarbylene (a hydrocarbylene chromium-ligand complex of formula (J)) or m is 2 and each RA independently is hydrocarbyl (a dihydrocarbyl chromium-ligand complex of formula (J)), wherein each hydrocarbyl or hydrocarbylene of RA independently is unsubstituted or substituted by from 1 to 5 RAS; each RAS independently is a neutral aprotic heteroalkyl, neutral aprotic heterocycloalkyl, neutral aprotic heteroaryl, or neutral aprotic aryl; when Cr formally is Cr+2, m is 1 and RA is hydrocarbyl (a hydrocarbyl chromium-ligand complex of formula (J)); k is an integer of 0 or 1; D is absent when k is 0 or D is a neutral ligand when k is 1; wherein the chromium-ligand complex of formula (J) is overall neutral and lacks a cyclopentadienyl-based (Cp-based) moiety. Also provided is a chromium catalyst comprising or prepared from the complex. Also provided is a process of making the catalyst and a process employing the chromium catalyst for polymerizing the olefin monomer, especially a straight chain 1-alkene, to prepare the polyolefin, especially a partially chain-straightened poly(1-alkene) or olefin block copolymer. Further provided is the partially chain-straightened poly(1-alkene) or olefin block copolymer prepared thereby. Also provided is a high throughput workflow.
Abstract:
A process to prepare polycarbamate comprising adding urea to a polyol in the presence of at least one catalyst selected from the group consisting of compounds having the following formula MmZn; wherein M is a divalent metal, and Z is an anionic functionality or a functionality capable of forming a covalent bond with M and wherein n times a valence number of Z equals X and m times two equals Y wherein the absolute value of X equals the absolute value of Y is provided. Also provided are a polycarbamate produced according to the process and a coating composition comprising the polycarbamate.
Abstract:
The present invention provides carbamylation compositions of one or more urea compounds, one or more polyols and a monovalent transition metal or alkali metal catalyst (i), such as lithium ethylhexanoate, which compositions are substantially isocyanate free, enjoy reduced toxicity in comparison to tin catalysts, and which are useful in making polycarbamates which themselves provide compositions for making crosslinked polyurethanes.