Abstract:
Procedimiento para la preparación de polímeros que contienen como monómero S-viniltioalcanol, mediante polimerización por radicales, caracterizado porque la polimerización es ejecutada en solución acuosa, con la condición de que para la preparación de los polímeros no se use N-vinilpirrolidona como monómero y que se use por lo menos otro monómero diferente de un S-viniltioalcanol, siendo el otro monómero un monómero con una insaturación monoetilénica soluble en agua, excepto vinilpirrolidona.
Abstract:
A method for producing a tridimensional structure comprises: (a) ejecting an object material through a first print head; (b) ejecting a first pre-supporting material through a second print head; (b′) ejecting a second pre-supporting material through a third print head, the pre-supporting materials comprising liquid components which form a solid supporting material when brought together; (c) radiation curing the object material; steps (a) to (c) are repeated several times in order to form the tridimensional structure layer by layer, and the object material and the supporting material comprise at least one common boundary surface; and (d) removing the cured supporting material by treatment with an aqueous medium. The supporting material is suitable for supporting overhanging components and structures located above hollow spaces. The use of a supporting material cured by a different mechanism than the object material prevents undesirable interactions between the object material and the supporting material during curing.
Abstract:
The invention relates to a method for producing isosorbide ethoxylate dimethacrylate by the transesterification of alkyl(meth)acrylate with isosorbide ethoxylate, comprising the following steps: (i) ethoxylating isosorbide to isosorbide ethoxylate; (ii) permitting alkyl(meth)acrylate to react with isosorbide ethoxylate in the presence of potassium phosphate as a catalyst and of a stabilizer and in the presence of an entrainer, forming an azeotrope with the alcohol bonded in the alkyl(meth)alcylate; (iii) continuously distilling off the azeotrope that consists of entrainer and alcohol, steps (ii) and (iii) being carried out simultaneously until isosorbide ethoxylate is substantially completely converted; (iv) separating the catalyst from the isosorbide ethoxylate dimethacrylate-containing product mixture; and (v) distilling off non-converted alkyl(meth)acrylate and entrainer from the product mixture.
Abstract:
A process for preparing mechanically stabilized polyazoles, comprising the following steps: I) treating at least one polyazole having at least one amino group in a repeat unit with a solution comprising (i) at least one strong acid and (ii) at least one stabilizing reagent, the total content of stabilizing reagents in the solution being in the range from 0.01 to 30% by weight, II) performing the stabilization reaction directly and/or in a subsequent processing step by heating to a temperature greater than 25°C, using at least one high-functionality polyether as the stabilizing reagent. The polyazoles thus obtainable are notable especially for a high conductivity and a very good mechanical stability. They are therefore especially suitable for applications in fuel cells.
Abstract:
A process for preparing solketal acrylate by transesterifying ethyl acrylate with solketal, comprising the steps of: (i) reacting ethyl acrylate with solketal in the presence of a catalyst comprising titanium(IV) or zirconium(IV) and a stabilizer in the presence of ethyl acrylate as azeotropic agent which forms an azeotrope with ethanol, (ii) continuously distilling off and condensing an azeotrope containing ethyl acrylate and ethanol by means of a distillation column operated under reflux conditions, wherein steps (i) and (ii) are conducted simultaneously until a solketal conversion of ≥ 95% is reached, characterized in that step (ii) is carried out by diluting the condensed azeotrope with additional ethyl acrylate and using this mixture as a reflux to the distillation column.
Abstract:
A process for preparing an aqueous polymer latex by polymerizing, optionally in the presence of a seed latex, a monomer composition containing solketal (meth)acrylate by radical emulsion polymerization in an aqueous polymerization medium in the presence of an acidic reacting radi- cal polymerization initiator, wherein the monomer composition comprises a) 0.1 to 100 % by weight of solketal (meth)acrylate, b) 0 to 99.9 % by weight of one or more further ethylenically unsaturated monomers, characterized in that an essentially neutral pH in the range of from 6 to 8 is maintained in the aqueous polymerization medium during the radical emulsion polymerization reaction by the presence of a basic compound.
Abstract:
La invención se refiere a composiciones que comprenden. a) del 1,00 al 65,00 % en peso de al menos un compuesto de fórmula (I), en la que R1, R2, R3, R4 son cada uno independientemente H, alquilo C1-C6, alcoxi C1-C6 o alcoxi C1-C6 -alquilo C1-C6; R es H o alquilo C1-C6; X es CR6R7, O o NR8; R6R7 son cada uno independientemente H, alquilo C1-C6, alcoxi C1-C6 o alcoxi C1-C6-alquilo C1-C6; R8 es H, alquilo C1-C6 o alcoxi C1-C6-alquilo C1-C6; k es 1, 2, 3, 4 ó 5, como componente A; b) 1,00 a 60,00% en peso de al menos un monómero que tiene dos grupos (met)acrilato y que tiene un peso molecular de no más de 500 Dalton, como componente B; c) 0 a 25% en peso de al menos un monómero que tiene al menos tres grupos (met)acrilato y que tiene un peso molecular de no más de 600 Dalton, como componente C; yd) 1,00 a 30,00% en peso de al menos un polímero que tiene al menos dos grupos (met)acrilato y que tiene un peso molecular de al menos 700 Dalton, como componente D; con la condición de que la cantidad de componentes A + B sea al menos del 50% en peso, así como el uso de estas composiciones como tintas de impresión, en particular tintas de impresión por chorro de tinta. (Traducción automática con Google Translate, sin valor legal)