Synthesis and characterization of ethoxyethyl α-cyanoacrylate and reaction intermediates

• Published in: Journal of applied polymer science 2003-03, Vol.87 (11), p.1758-1773
• Main Authors: Hwang, Yu-Haur, Hwang, Chi-Ping, Tsiang, Raymond Chien-Chao, Chen, Michael
• Format: Article
• Language: English
• Subjects: adhesive; Applied sciences; ethoxyethyl cyanoacetate; ethoxyethyl α-cyanoacrylate; Exact sciences and technology; formaldehyde; oligomer; Organic polymers; Physicochemistry of polymers; Polycondensation; Preparation, kinetics, thermodynamics, mechanism and catalysts
• ISSN: 0021-8995; 1097-4628
• DOI: 10.1002/app.11508

Ethoxyethyl α‐cyanoacrylate was synthesized by first making oligo(ethoxyethyl α‐cyanoacrylate) through a condensation reaction of ethoxyethyl cyanoacetate with paraformaldehyde, followed by a depolymerization of the oligomer at an elevated temperature in an acidic atmosphere with a high vacuum. The ethoxyethyl cyanoacetate was in turn synthesized from an esterification of ethoxyethanol and cyanoacetic acid. The molecular structure of the target monomer and the corresponding intermediates were corroborated by IR and 1H‐NMR. Solvents having a lower polarity led to the formation of oligomers having higher molecular weights. The molecular weight distribution of the oligomer revealed that the reaction of ethoxyethyl cyanoacetate with formaldehyde followed a mechanism comprising monomer activations, anionic reactions, and chain scissions. DSC thermograms demonstrated the cured ethoxyethyl α‐cyanoacrylate was nearly amorphous, containing little or low crystallinity. Mechanical testing data indicated that the cured ethoxyethyl α‐cyanoacrylate was a hard adhesive with higher toughness than the conventional ethyl α‐cyanoacrylate. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1758–1773, 2003