摘要:
Phenolic polyether polyols are prepared by a two stage oxyalkylation process, a first stage performed at a high oxyalkylation temperature and a second stage at a lower oxyalkylation temperature. Despite the use of high temperature during oxyalkylation, polydispersity is substantially unaffected, while process time is drastically reduced.
摘要:
A water-dispersible polyurethane resin is disclosed. The resin comprises recurring units of an alkoxylated phenolic resin, a carboxylate-containing diol, and a multifunctional isocyanate. The resin, which can be neutralized, and/or chain-extended, is dispersed in water to form a polyurethane dispersion. Coatings derived from the polyurethane dispersions have excellent acid and chemical resistance.
摘要:
Epoxides are produced by an integrated process involving molecular oxygen oxidation of an alkylammonium salt of a sulfonic acid-substituted anthrahydroquinone, epoxidation of an ethylenically unsaturated substrate using the hydrogen peroxide-containing product obtained by such oxidation in the presence of a titanium silicalite catalyst, and regeneration of the anthrahydroquinone by hydrogenation of the anthraquinone co-product. Oxidation and epoxidation may be performed concurrently. The alkylammonium salts have the advantage of being highly soluble in polar protic media such as water and lower alcohols.
摘要:
A selective process for the preparation of diphenylmethane diisocyanate precursors is disclosed. An alkyl phenylcarbamate or an N,N-dialkyl-N'-phenylurea is reacted with a methylene bis(alkyl carbamate) in the presence of an acid catalyst. The use of a staged addition of phenylcarbamate or phenylurea to the methylene bis(carbamate) and the use of a ramped temperature program are the keys to good selectivity to MDI dimer products.
摘要:
A moisture-cure urethane composition is disclosed. The urethane is formulated from an NCO-terminated alkoxylated phenolic resin that has long oxyalkylene chains. It has greater than 70 wt % solids and has excellent resistance to acids, bases, and chemicals.
摘要:
Hydrogen peroxide is produced by oxidizing alkylammonium salts of sulfonic acid-substituted anthrahydroquinones. As said salts are highly soluble in protic polar solvents such as water and lower aliphatic alcohols, the concentration of hydrogen peroxide in the reaction product thereby obtained may be advantageously high. The anthraquinone salt co-product generated by such oxidation may be readily converted in high yield back to the starting anthrahydroquinone salt by hydrogenation.
摘要:
Hydrogen peroxide is produced by oxidizing alkylammonium salts of sulfonic acid-substituted anthrahydroquinones. As said salts are highly soluble in protic polar solvents such as water and lower aliphatic alcohols, the concentration of hydrogen peroxide in the reaction product thereby obtained may be advantageously high. The anthraquinone salt co-product generated by such oxidation may be readily converted in high yield back to the starting anthrahydroquinone salt by hydrogenation.
摘要:
A selective process for the preparation of diphenylmethane bis(dialkylureas) is disclosed. An alkyl phenylcarbamate or an N,N-dialkyl-N'-phenylurea is reacted with a methylene bis(alkyl carbamate) in the presence of an acid catalyst. The use of a staged addition of phenylcarbamate or phenylurea to the methylene bis(carbamate) and the use of a ramped temperature program are the keys to good selectivity to MDI dimer products.