Modification of Cyanoacrylate Adhesives

The review shows the ability of cyanoacrylate adhesives (CA) to bond metals, glass, rubber, leather and many plastics in various combinations almost instantaneously, which has led to widespread use in both industry and households. In the patent and scientific literature, inventions and studies related to solving the problem of increasing the adhesive strength and heat resistance of adhesive compositions are widely represented. It has been shown that target audiences are perfectly suited for use on plastic or rubber substrates. It is noted that there are two ways to improve the heat resistance of the target audience on metal surfaces by adding monomeric materials that increase the glass transition temperature and slow down decomposition during depolymerization and additives that improve the thermal stability of the polymer and adhesion at the polymer-substrate interface at elevated temperatures. The use of aromatic compounds as additives to the target audience, such as nitrobenzene, 1,2-dichlorobenzene, 1,2,4-trichlorobenzene and bromo-chlorobenzene in combination with fillers, is shown. The addition of succinic, phthalic anhydride or maleic anhydride to ethyl-2-cyanoacrylate (ECA) can increase the heat resistance of the adhesive. The creation of compositions with two double bonds based on allyl cyanoacrylate or a series of bis-cyanoacrylates made it possible to make significant progress in solving this problem. The allyl group can undergo thermally induced cross-linking by a free radical mechanism. Biscyanoacrylates are capable of easy cross-linking and improving the performance of adhesive joints. The areas of application of the target audience in medicine, vein surgery, tissues and dentistry are expanding due to the high initial adhesive strength of the adhesive bond of tissues and the ability to subsequent self-resorption of the adhesive joint with minimal traumatic exposure and low toxicity. The next step towards effective modification of the target audience is the reaction along the main [CH2-C(R)] chain of polycyanoacrylates with polymeric para-dinitrosobenzene (PDNB). The mechanism of increasing resistance to thermal aging and long-term exposure under atmospheric conditions is explained by polymer-similar transformations in the methylene atom of poly-ECA with depolymerized PDNB, followed by the formation of a polar azomethine fragment and the formation of additional intermolecular hydrogen bonds with the model surface of the metal oxide film.