CYANOACRYLIC ESTER POLYMERS

The polymers of the 2-cyanoacryhc esters, more commonly known as the alkyl 2-cyaiioacrylates, are hard glassy resins that exhibit excellent adhesion to a wide variety of materials. The polymers are spontaneously formed when their Hquid precursors or monomers are placed between two closely fitting surfaces. The spontaneous polymerisation of these very reactive Hquids and the excellent adhesion properties of the cured resins combine to make these compounds a unique class of single-component, ambient-temperature-curing adhesives of great versatiUty. The materials that can be bonded mn the gamut from metals, plastics, most elastomers, fabrics, and woods to many ceramics. 

The utihty of these adhesives arises from the electron-withdrawing character of the groups adjacent to the polymerizable double bond, which accounts for both the extremely high reactivity or cure rate and thek polar nature, which enables the polymers to adhere tenaciously to many diverse substrates. 

The physical properties of the monomers must be discussed along with those of the cured polymers because consideration of one without the other presents an incomplete picture. The 2-cyanoacryhc ester monomers are all thin, water-clear Hquids with viscosities of 1 3 mPa-s(=cP). Although a number of the esters have been prepared and characterized, only a relative few are of any significant commercial interest, and, of those, the methyl and ethyl esters by far predominate. The physical properties of the principal monomers are included in Table 1. 

The basic polymerization reaction is described by the foUowing equations. 

Kirk-Othmer Encyclopedia of Chemical Technology (4th Edition) 

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Acrylic Ester Polymers, 2-Cyanoacrylic Ester Polymers" ia ECT 3rd ed., VoL 1, pp. 408—413, by H. W. Coover, Jr., andj. M. Mclatire, Tennessee Eastman Company. 

ACRYLIC ESTER P OLYMERS - 2-CYANOACRYLIC ESTER POLYMERS] (Vol 1)... 

The cured 2-cyanoacrylic ester polymers are relatively nontoxic. Oral doses of 6400 mg /kg failed to kill laboratory rats. Mild skin irritation was observed widi guinea pigs, but diere was no evidence of sensitization or absorption through die skin (15). 

The structure—property relationships for the lower cyanoacrylic ester polymers generally indicate that cure rates, tensile strength, tensile shear... 

Coover, H. W. and McIntyre, J. M. 1985. 2-Cyanoacrylic ester polymers. In Encyclopedia of Polymer Science and Engineering, Vol. Kroschwitz, ed., p. 161. Interscience, New York. 

Cyanoacrylic Ester Polsaners in EPST 1st ed., Vol. 1, pp. 337-342, by H. W. Coover Jr. and T. H. Wicker Jr., Tennessee Eastman Co., a division of Eastman Kodak Co., Acrylic and Methyacrylic Ester Polsmiers, 2-Cyanoacrylic Ester Polymers in EPSE 2nd ed., Vol. 

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