Cyanoacrylate-based adhesives

Abstract

The effect the curing conditions on the properties of adhesive joints formed using cyanoacrylatebased adhesives is investigated. The temperature dependences of relative rigidity and mechanical loss tangent are studied by torque analysis for poly(ethyl-, allyl-, allyloxyethyl-, allyloxyisopropyl-, propargyloxyethyl-, and propargyl-) cyanoacrylates after their thermal treatment in the temperature range of 20-250 ° C. The glass transition parameters of polycyanoacrylates and the dependence of the curing intensity on the structure of initial monomers and polymers are determined. It is established that the elastic modulus decreases with the lengthening of alkyl radicals in side chains. A list is experimentally determined of monomers used to obtain adhesive compositions with stable physicomechanical properties and heat resistances of up to 250 ° C.

Structural and adhesion properties of poly(ethyl 2-cyanoacrylate) post-cured at different temperatures and times

“…The decrease in the shear strength values of the post-cured joints made with ECN is in agreement with previously reported studies made with composite-ethyl cyanoacrylate [6] and steel-ethyl cyanoacrylate [7] joints. The decrease in the shear strength values of the joints made with ECN after being post-cured can be related to Figure 7.…”

“…Furthermore, the solvent used as polymerization initiator determined the nanoparticle size and the polydispersity of poly(ethyl cyanoacrylate)s. These results have been explained by the co-existence of two different polymerization mechanisms, i.e., interfacial precipitation of pre-formed polymer and interfacial polymerization. The influence of the temperature on the polymerization of ethyl cyanoacrylate has been studied elsewhere [2][3][4][6][7][8], but different conclusions have been obtained depending on the polymerization conditions. For example, the particle size of poly(ethyl 2-cyanoacrylate)s (pECNs) has been related to the polymerization temperature by Reddy et al [2] whose have demonstrated that the higher was the polymerization temperature, the larger was the polymer particle size because of some agglomeration of particles was produced.…”

“…On the other hand, Senchenya et al [6] have studied the influence of the polymerization temperature on the adhesion properties of different cyanoacrylates. They have demonstrated that the polymerization at high temperature decreased the adhesion because of the thermal degradation of the cyanoacrylate was favoured.…”

Resina acrílica de curado de alta velocidad

“…Los iones metálicos presentes en coordinación con el material depositado, mejoran la reactividad del doble enlace de la molécula del 2-cianoacrilato, por lo que la reacción de polimerización se ve favorecida. Este proceso produce un polímero lineal de estructura regular tipo cabeza-cola en los que se ven favorecidos enlaces entre radicales metil, etil, butil y alil de 2-cianoacrilatos, especialmente en la producción de adhesivos comerciales [3].…”

“…Los reactivos de curado frecuentemente presentan tres o más grupos funcionales por molécula. El agente de curado debe tener muchos grupos funcionales dado que favorecen el entrecruzamiento de las cadenas [3].…”