Processo para a preparação de bis-cianoacrilatos

摘要

PCT No. PCT/EP95/02049 Sec. 371 Date Mar. 5, 1997 Sec. 102(e) Date Mar. 5, 1997 PCT Filed May 30, 1995 PCT Pub. No. WO95/33708 PCT Pub. Date Dec. 14, 1995Biscyanoacrylates in solution are prepared by reacting 2-cyanoacrylic acids or their alkyl esters with diols in the presence of sulfonic acids as catalysts. The reaction mixture is processed by substituting an aliphatic solvent for the aromatic solvent and is then subjected twice to fractional crystallization. The thus obtained biscyanoacrylates are very pure. They are therefore useful for producing storage stable cyanoacrylate adhesives. Their admixture increases the thermal resistance of the adhesives, which is particularly important in the case of electric and electronic components.