Reference

Triethylene glycol dimethacrylate

Triethylene glycol dimethacrylate. Crucean, Augustin Constantin; Stanulet, Lucica; Sandru, Dan Petru; Czifra, Rozalia; Beghecian, Marius Octavian Gheorghe (Institutul de Cercetari Produse Auxiliare Organice, Medias, Rom.). Rom. RO 81794 B 30 May 1983, 3 pp. (Romanian). (Romania). CODEN: RUXXA3. CLASS: IC: C07C069-54. APPLICATION: RO 81-105665 29 Oct 1981. DOCUMENT TYPE: Patent CA Section: 38 (Plastics Fabrication and Uses) Section cross-reference(s): 23 Mixts. of phenothiazine (I) [92-84-2] with Ph2NH [122-39-4], a-nitroso-b-naphthol [131-91-9], or methylene blue [61-73-4] are used as polymn. inhibitors in the esterification of methacrylic acid (II) with triethylene glycol (III) [112-27-6] to give a product contg. 53-83% title compd. (IV) [109-16-0], which was useful as an anaerobic adhesive. Thus, I 2.063, Ph2Na 0.0004, III 300.36, II 416.07, and H2SO4 13.2057 g were heated 10 h at 100-126°, while the water-of-reaction was removed by an azeotrope with PhMe, to give 97. 112-27-6 and 61-73-4 which are cas registry numbers of chemicals are mentioned.20% crude ester. This crude ester was purified to give a mixt. contg. diethylene glycol dimethacrylate 18.2, IV 77.5, and tetraethylene glycol mono- and dimethacrylate 3.8%, which was stable for 2 h 25 min at 82° when used as an anaerobic adhesive for metals. .

The pKa value of redox indicators on graphite electrodes

The pKa value of redox indicators on graphite electrodes. Huck, H. (TU Muenchen, Freising-Weihenstephan D-8050, Fed. Rep. Ger.). Ber. Bunsen-Ges. Phys. Chem., 87(10), 945-50 (German) 1983.In this article, certain chemicals are used. Some of their cas registry numbers are 131-91-9 and 87-88-7 CODEN: BBPCAX. ISSN: 0005-9021. DOCUMENT TYPE: Journal CA Section: 66 (Surface Chemistry and Colloids) Section cross-reference(s): 72, 79 The redox potentials were detd. of adsorbed weak arom. acids (A) and their conjugate bases (B) on graphite electrodes at different pH's by cyclic voltammetry to obtain the apparent logs of the acidities pKa,ad. The desorption velocities are given. The difference between surface and bulk pKa,ad values is due to the charges of the adsorbed substances. Ion pairing is described. The adsorbed mol. electronic structure affects the pKa,ad only if the mol. has p-conjugation which is easily polarized by the electrode elec. field. .