摘要:
Method to obtain methylene malonate and related monomers following a bis(hydroxymethyl) malonate pathway. A bis(hydroxymethyl) malonate intermediary is subsequently reacted (i.e., subjected to thermolysis) to provide a methylene malonate monomer species. A source of formaldehyde (e.g., formalin) is provided in the presence of a basic catalyst (e.g., calcium hydroxide), to which a malonate (e.g., diethyl malonate) is added under suitable reaction conditions to obtain the desired intermediary (e.g., dialkyl bis(hydroxymethyl) malonate). The intermediary is reacted (i.e., subjected to thermolysis) under suitable conditions in the presence of a suitable catalyst (e.g., a zeolite) to obtain a methylene malonate monomer. In an exemplary embodiment, the thermolysis reaction includes the addition of the bis(hydroxymethyl) malonate intermediary onto a heated catalyst. The reaction product is collected and purified. The disclosed methods may be performed in a continuous operation. Discrete steps may be performed by using modular units within a plant.
摘要:
A process for producing water-absorbing polymer particles with low caking tendency and high absorption under pressure, comprising polymerization of a monomer solution or suspension, drying of the resulting polymer gel, grinding, classifying, thermal surface postcrosslinking and coating with silicon dioxide, wherein the water-absorbing polymer particles have been coated, before, during or after the surface postcrosslinking with aluminum cations.
摘要:
The use of aqueous solutions or dispersions of copolymers composed ofA) from 5 to 95 mol % of ethylenically unsaturated mono- or dicarboxylic acids having 3 to 10 carbons, their anhydrides, their alkali metal, alkaline earth metal or ammonium salts, or mixtures thereof,B) from 5 to 95 mol % of ethylenically unsaturated acetals, ketals or orthocarboxylic esters of the formula I ##STR1## where R.sup.1 to R.sup.12 independently are hydrogen or an organic radical anda to d independently are 0 or 1, andC) from 0 to 70 mol % of other copolymerizable monomersor their hydrolysis products or polymer-analogous reaction products, as tanning agents for the self-tanning, pretanning or assist tanning of leather pelts and skin pelts or for the retanning of leather and skins.
摘要:
Copolymers comprise a) from 1 to 65 mol % of at least one diketene of the general formula I ##STR1## where R.sup.1 and R.sup.2, independently of one another, are each hydrogen or C.sub.1 -C.sub.30 -alkyl, b) from 30 to 70 mol % of at least one ethylenically unsaturated dicarboxylic acid or one dicarboxylic acid derivative, c) from 0.5 to 60 mol % of at least one ethylenically unsaturated hydrocarbon and d) up to 20 mol % of at least one further ethylenically unsaturated monomer, modified copolymers are obtainable by reacting these copolymers with NH-, SH- and/or OH-functional compounds, and the unmodified or modified copolymers are used as additives for mineral oil middle distillates.
摘要:
Copolymers based on ethylenically unsaturated dicarboxylic anhydrides, long-chain olefins and fluoroolefins Copolymers containing 10 to 60% by weight of bivalent structural units of the formula A ##STR1## wherein R.sup.1 and R.sup.2, independently of one another, are hydrogen or C.sub.1 -C.sub.6 -alkyl,a and b are zero or one and a+b is one,X and Y are identical or different and are the group --N--HR.sup.3,where R.sup.3 is C.sub.1 -C.sub.40 -alkyl, C.sub.3 -C.sub.40 -alkenyl, C.sub.5 -C.sub.20 -cycloalkyl or C.sub.6 -C.sub.18 -aryl, the group --N--(R.sup.3).sub.2,where R.sup.3 are identical or different and have the abovementioned meaning, and/or the group --O--R.sup.4,where R.sup.4 is hydrogen, an alkali metal cation, one equivalent of an alkaline earth metal ion, a cation of the formula H.sub.2 N.sup..sym. (R.sup.3).sub.2 or H.sub.3 N.sup..sym. R.sup.3, C.sub.1 -C.sub.40 -alkyl, C.sub.5 -C.sub.20 -cycloalkyl or C.sub.6 -C.sub.18 -aryl, 30 to 89% by weight of bivalent structural units of the formula B ##STR2## wherein R.sup.5 is hydrogen or C.sub.1 -C.sub.4 -alkyl andR.sub.6 is C.sub.6 -C.sub.40 -alkyl or C.sub.6 -C.sub.18 -aryl, and1 to 20% by weight of bivalent structural units of the formula C ##STR3## wherein n is a number from 6 to 24.The invention also relates to a process for the preparation of these copolymers and to the utilization thereof.
摘要:
Polymers are disclosed which comprise the reaction product of (A) at least about 60 weight percent of at least one .alpha., .beta.-unsaturated polycarboxylic acid or anhydride; and (B) about 0.5 to about 40 weight percent of at least one acrylamide represented by the formula VI:CH.sup.2 .dbd.C(R.sup.5)C(O)N(R.sup.6)R.sup.7 (VI)wherein R.sup.5, R.sup.6 and R.sup.7 are each independently hydrogen or lower alkyl groups provided that at least one of R.sup.6 and R.sup.7 is a lower hydro-carbyl group, and further provided that the mixture is free of a vinyl sulfonic acid. The monomers react at elevated temperatures to form polycarboxylate scale inhibitors having a number average molecular weight of from about 400 to 10,000. The polymers have particular application in the inhibition of scales during oil field operations, but also may be employed in any environment where deposition of mineral scales is undesirable.
摘要:
A novel polyfunctional maleimide-based thermosettable resin composition comprising: (a) at least one polyfunctional maleimide compound selected from the group consisting of bismaleimide and polymaleimide, and (b) at least one ether derivative of an alkenylphenol.
摘要:
Copolymers of average number molecular weight from about 300 to 5,000 comprising recurrent units originating (A) from alpha olefins, (B) from .alpha.,.beta. unsaturated .alpha., .gamma. dicarboxylic compounds, (C) from unsaturated acid esters of 1,2-diols, optionally etherified or esterified, and (D) optionally from acrylic esters, the proportions of the recurrent units being 5-60% for (A), 10-70% for (B), 10-60% for (C) and 0-60% for (D), at least one of recurrent units (A), (B) and/or (C) comprising at least 12 carbon atoms, and at least 10% of the recurrent units of said copolymer being (B) recurrent units of N-substituted imide type. These copolymers form additives useful to lower the pour point of middle distillates, particularly of gas-oils. The use of said additives at a concentration from 0.001 to 2% by weight results in a substantial decrease of the pour point of the treated middle distillates.
摘要:
Novel heat-resistant maleimido polymers, well adopted for the production of molded/laminated shaped articles, are copolymerizates of (a) a hydrocarbyl N,N'-bis(maleimide); (b) a diamine containing a diorganopolysiloxane bridge; optionally, (c) an N,N'-bis(maleimide) containing a diorganopolysiloxane bridge; optionally, (d) at least one other comonomer copolymerizable therewith; and, optionally, (e) a catalyst therefor.
摘要:
A light-sensitive recording material which provides polymer images and contains, on a base, a layer of a photocrosslinkable polymer with an average molecular weight of 10.sup.3 to 10.sup.6, the copolymer having been prepared from(1) a (meth)acrylate, (meth)acrylamide or vinyl ether derivative which contains at least one maleimide group of the formula ##STR1## in which R.sub.1 and R.sub.2 are each alkyl having 1 to 4 carbon atoms, or R.sub.1 and R.sub.2 together with the carbon atoms to which they are bonded form a 5-membered or 6-membered carbocyclic ring,(2) an ethylenically unsaturated comonomer containing acid groups, this comonomer being present in an amount of at least 18 percent by weight, based on the total amount of the comonomers, and, optionally,(3) at least one further ethylenically unsaturated comonomer which differs from the comonomers (1) and (2).