摘要:
Novel amorphous copolyamides are provided which are the product of reaction of (A) a lactam, (B) a bisimidazoline, and (C) a dicarboxylic acid, wherein the proportions of reactants based on 100 mole percent are from about 43 to about 82 mole percent of lactam (A) and the remaining 18 to 57 mole percent divided between said (B) and said (C) in substantially equimolar proportions.The copolyamides are characterized by better resistance to elevated temperatures than 100 percent polycaprolactam polyamides but at the same time are easily molded because of their amorphous character.
摘要:
A process for making glycerol di-tert-butyl ethers is disclosed. In one aspect of the invention, glycerol and isobutylene react in the presence of a β-zeolite having a silicon to aluminum ratio greater than 150. In another aspect, the etherification is performed in the presence of a β-zeolite and added tert-butyl alcohol. Each process selectively provides glycerol di-tert-butyl ethers while reducing the generation of isobutylene dimers and trimers. Utilizing both aspects of the inventive process simultaneously affords a diether product mixture containing less than 5 wt. % of isobutylene oligomers.
摘要:
This invention relates to a multi-step process for isolating a cyclotrimerized isocyanate from mixture containing said cyclotrimerized isocyanate plus an isocyanate oligomer which comprises the steps of: (a) contacting said mixture with a liquid solvent to provide a solvent-containing mixture, (b) extracting said solvent-containing mixture by liquid-liquid extraction to cause said solvent-containing mixture to elute into an extractate and a residue, wherein said extractate is a cyclotrimerized isocyanate that is essentially oligomer-free and is further characterized by having reduced viscosity relative to said solvent-containing mixture, and (c) separating uncyclotrimerized monomer from said extractate to provide a reduced viscosity trimer product that is essentially free of monomer. Also disclosed is the reduced-viscosity product produced by this process.
摘要:
A gypsum composition containing a sulfonate-containing comb-branched copolymer is disclosed. The sulfonate-containing comb-branched copolymer comprises recurring units of a polyether macromonomer, an acrylic monomer, and a sulfonate monomer. The sulfonate-containing comb-branched copolymer not only increases the fluidity of gypsum slurry but also has reduced retardation on the gypsum setting.
摘要:
A process for preparing isocyanate adducts having a high proportion of monoisocyanurate using a quaternary ammonium carboxylate trimerization catalyst. Also claimed are specific carboxylate catalysts, together with a process for producing the catalysts. The catalysts are particularly useful for trimerizing hexamethylene diisocyanate and isophorone diisocyanate.
摘要:
Disclosed is a method for the trimerization of organic isocyanates comprising thermally activating, in the presence of said isocyanates, a catalyst comprising a carboxylic acid salt selected from the alkali metal salts or quaternary ammonium salts of particular substituted malonic acids or half-esters thereof, particular carbamyl substituted aliphatic acids, or triaryl acetic acids.Mixtures of the catalysts with isocyanates have surprisingly long periods of stability at ambient temperatures (about 20.degree. C.) which makes the present method particularly suitable to systems for molding polyiso-cyanurates wherein long open times are required of a resin pre-mix prior to the actual curing step.
摘要:
Disclosed are new coatings compositions based on an HDI isocyanurate or biuret polyisocyanate and a bis(imine) reaction product of a diaminoalkane containing between two and five carbon atoms with an alkyl aldehyde containing between four and seven carbon atoms (advantageously a bis(imine) product of the reaction of 1,4-diaminobutane and isobutyraldehyde). The latter bis(imine) is completely miscible in HDI isocyanurate and biuret polyisocyanates, and, as a reactive diluent, allows the preparation of high performance coatings formulations that require only small amounts of solvents to achieve a conveniently sprayable viscosity.
摘要:
Disclosed is a method for the trimerization of organic isocyanates comprising thermally activating, in the presence of said isocyanates, a catalyst comprising a carboxylic acid salt selected from the alkali metal salts or quaternary ammonium salts of particular substituted malonic acids of half-esters thereof, particular carbamyl substituted aliphatic acids, or triaryl acetic acids.Mixtures of the catalysts with isocyanates have surprisingly long periods of stability at ambient temperatures (about 20.degree. C.) which makes the present method particularly suitable to systems for molding polyisocyanurates wherein long open times are required of a resin pre-mix prior to the actual curing step.
摘要:
Described are compounds characterized by the following formula: ##STR1## wherein C.sub.n H.sub.2n is alkylene from 2 to 12 carbon atoms and C.sub.m H.sub.2m is alkylene from 2 to 20 carbon atoms. Each of the alkylene groups can, optionally, be substituted by inert substituents. The compounds contain a free isocyanato group and a masked isocyanate group, namely, the cyclic urea moiety, which, when the compounds are heated, preferably in the presence of a catalyst, opens to give the group OCN--C.sub.n H.sub.2n --. Thus, the compounds can be reacted via the free isocyanate group with active hydrogen-containing monomers or polymers to form storage stable compositions which, upon heating, are curable via reaction with the cyclic urea group.
摘要翻译:描述了以下式表征的化合物:其中C n H 2n是2至12个碳原子的亚烷基,C m H 2m是2至20个碳原子的亚烷基。 每个亚烷基可任选地被惰性取代基取代。 化合物含有游离异氰酸酯基和掩蔽的异氰酸酯基团,即环脲部分,当化合物被加热时,优选在催化剂存在下,打开以得到OCN-C n H 2n - 基团。 因此,化合物可以通过游离异氰酸酯基团与活性含氢单体或聚合物反应,形成储存稳定的组合物,其在加热时可通过与环脲基团的反应固化。
摘要:
Bis(cyclic ureas) are disclosed which have the formula ##STR1## wherein R is ##STR2## and C.sub.n H.sub.2n is ethylene or 1,3-propylene each of which can be substituted by one or more inert substituents.These compounds are useful as masked diisocyanates which, on heating in the presence of a polyol and, optionally, a polyurethane catalyst, give rise to polyurethane resins. Accordingly, they are useful as a component of storage stable compositions which are convertible to polyurethanes upon heating. Such compositions are particularly useful as solvent-less coating compositions. The properties of the above compounds are distinguished in a number of respects from the known bis(cyclic ureas) in which C.sub.n H.sub.2n has 4 or more carbon atoms in the chain between the valencies. Illustratively, the above compounds are more stable on exposure to heat in the absence of catalysts but, in the presence of polyurethane catalysts, react with polyols at a significantly faster rate than the prior art compounds.
摘要翻译:公开了具有式“IMAGE”的双(环脲),其中R为“IMA”,C n H 2n为乙烯或1,3-亚丙基,各自可被一个或多个惰性取代基取代。 这些化合物可用作掩蔽的二异氰酸酯,其在多元醇和任选的聚氨酯催化剂存在下加热时产生聚氨酯树脂。 因此,它们可用作储存稳定组合物的组分,其可在加热时转化为聚氨酯。 这样的组合物特别可用作无溶剂涂料组合物。 上述化合物的性质在许多方面与众所周知的双(环脲)有关,其中C n H 2n在链中具有4个或更多个碳原子。 说明性地,上述化合物在不存在催化剂的情况下在暴露于热下更稳定,但是在聚氨酯催化剂的存在下,与多元醇以比现有技术化合物更快的速率反应。