SynopsisThis paper gives the results of the estimated coagulum content in the final sample of a dispersion based on styrene-butylacrylate-acrylic acid, prepared by semicontinuous emulsion polymerization. The results were gained from experiments on 25 L and 5 m3 reactors. The dependence of the amount of coagulum on the agitation intensity was studied. It was found that it is necessary to divide the results into two regions: (a) for specific power input smaller than 80 W/m3; (b) for specific power input greater than 80 W/m3. It was found that polymerization scaling up from the point of constant coagulum content in the system studied is possible under the conditions of constant specific power input. The specific power input varied in the range from 5 to 3000 W/m2. For the first region was gained the empiric correlation Y = 2.16(gV)-' and for the second region the equation Y = 3.5 X 10-5(8v)1.5, where Y is the amount of coagulum (wt W).For the existence of two regions we propose the following hypothesis according to which increasing mixing intensity improves the temperature and concentration nonuniformity which results in the decrease of coagulum content. From the certain value of specific power input, which is specific for each system, the amount of coagulum starts to increase due to increasing shear stress.
ZUSAMMENFASSUNG:In dieser Arbeit wurde die h d e r u n g der Konzentration der Reaktionskomponenten mit der Zeit bei der Reaktion eines hOhermolekularen Epoxidharzes mit Tetrahydrophthalsaure-und 3-Chlortetrahydrophthalstiureanhydrid in Anwesenheit von Lauryldimethylbenzylammoniumbromid verfolgt. Diese Messungen wurden im technischen Manstab wie bei der Verarbeitung der Komponenten im Extruder gemacht.Die Reaktion wurde im Temperaturbereich von 363,2 -403,2 K, d. h. in der N&e des Erweichungspunktes des Harzes durchgeftkhrt. Die gemessenen Konzentrationswerte der einzelnen reagierenden Gruppen i m Reaktionssystem wurden in Abhtlngigkeit von der Zeit mit Hilfe der ftkr die Folgereaktionen nach zweiter Ordnung geltenden kinetischen Beziehungen ausgewertet. Diese Auswertung wurde in der Anfangsphase der Reaktion durchgeftihrt. Es zeigte sich beim Vergleich aller drei bei 383,2 K gemessenen Systeme, da8 das System mit 3-Chlortetrahydrophthalstiureanhydrid den grO8ten Wert der Geschwindigkeitskonstante kl = 8,397 * kg s-l mol-' (giiltig ftkr die Bildung von Monoestern) und den niedrigsten Wert der Geschwindigkeitskonstante k, = 1,345 * kg s-I mol-' (gtiltig fur die Bildung von Diestern und daher von der vernetzten makromolekularen Struktur) aufweist. SUMMARY:The change of time of the concentration of components in the reaction of the higher molecular epoxy resin with tetrahydrophthalic and 3-chlorotetrahydrophthalic anhydrides in the presence of lauryldimethylbenzyl ammoniumbromide was investigated. These investigations were carried out in correspondence with the technical conditions for the reaction components in extruder. The reaction was carried out in the temperature range of 363.2 -403.2 K, thus near the softening point of the resin. The measured values of concentration of the particular groups in the reaction were evaluated as time dependence by means of kinetic relations applicable to second order consecutive reactions. This evaluation was carried out in the initial phase of the reaction. In comparison of the three investigated systems measured at the temperature of 383.2 K, 3-chlorotetrahydrophthalic anhydride has the highest value of the reaction constant kl = 8.397 * lo-' kg s-l mol-' (applicable to the monoester forma-0 1986 Hilthig & Wepf Verlag, Basel
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