Cyanoacrylate resins

Similar to the primers developed for cyanoacrylate resins, the solvent carrier plays an important role in facilitating interdiffusion of the primer and the substrate. Fig. 12 shows a schematic view of the top few microns of an injection molded TPO surface. 

Lee, H. (Ed.), Cyanoacrylate Resins — The Instant Adhesives. Pasadena Technology Press, Los Angeles, CA, 1986. 

Lee, H. ed. Cyanoacrylate Resins—The instant Adhesives Monograph, Pasadena... 

Cyanoacrylate Resins, edited by H. Lee, 1981, 241 pp., T/C Press. Covers history, synthesis of various monomers, compounding, and applications. 

H. Lee, ed.. Cyanoacrylate Resins, Pasadena Technol. Press, Pasadena, California, 1981. 

Hydrolysis has been established for epoxy, polyurethane, and cyanoacrylate resins. In the case of conventional elastomers, polysulfides, polyurethanes, and acrylic rubbers have all shown sensitivity to moisture. Hydrolysis causes the breaking of bonds within the polymer. Thus the strength decreases. However, before this occurs the part usually swells and may cause deformation before hydrolysis can completely act. For electronic sealants and casting materials, it is highly desirable to keep moisture from penetrating into critical areas. Hydrophobic polymers have been... 

Unlike other adhesive resins, in which polymerization is performed by a radicalic mechanism, cyanoacrylate resins (CNAs) polymerize anionically, according to the reaction... 

Anerobic adhesives. Acrylate acid diester and cyanoacrylate resins are called anaerobic adhesives because they cure when air is excluded from the resin. Anaerobic resins are noted for being simple to use, one-part adhesives, having fast cure at room temperature and high cost. However, the cost is moderate when considering a bonded-area basis because only a small volume of adhesive is required. Most anaerobic adhesives do not cure when gaps between adherend surfaces are greater than 10 mils, although some monomers have been developed to provide for thicker bond-lines. 

The cyanoacrylate adhesives are more rigid and less resistant to moisture than acrylate acid diester adhesives. They are available only as low-viscosity liquids that cure in seconds at room temperature without the need of a primer. The cyanoacrylate adhesives bond well to a variety of substrates, as shown in Table 7.25, but have relatively poor thermal resistance. Modifications of the original cyanoacrylate resins have been introduced to provide faster cures, higher strengths with some plastics, and greater thermal resistance. 

Acrylic monomers Cyanoacrylates Urea formaldehyde resins... 

Polymeric materials are commonly used for bonding materials. Impact or contact adhesives are mainly based on highly crystalline polychloroprene (Neoprene), NR latex is used as a flexible adhesive very suitable for use with fabrics. Rigid adhesives based on materials such as polystyrene cement, epoxy resin or cyanoacrylates are suitable for bonding of rigid materials. The bond is provided by intramolecular forces between the adhesive and the adherend. Adiabatic... 

Reactive adhesives Reactive adhesives are either low molecular weight polymers or monomers that solidify by polymerization and/or cross-linking reactions after application. Cyanoacrylates, phenolics, silicon rubbers, and epoxies are examples of this type of adhesive. Plywood is formed from impregnation of thin sheets of wood with resin, with the impregnation occurring after the resin is placed between the wooden sheets. 

Ihe polymers of the 2-cyanoacrylic esters, more commonly known as the alkyl 2-cyanoacrylates, are hard glassy resins that exhibit excellent adhesion to a wide variety of materials. The polymers are spontaneously formed when their liquid precursors or monomers are placed between two closely fitting surfaces. Tile spontaneous polymerization of these very reactive liquids and the excellent adhesion properties of the cured resins combine to make these compounds a unique class of single-component, ambient-temperature-curing adhesive of great versatility (Table 3). The materials that can be bonded run the gamut from metals, plastics, most elastomers, fabrics, and woods to many ceramics. 

The common surface preparation treatment for epoxy resins is to wipe with solvent, mechanical abrasion, and final solvent cleaning. Epoxy parts can be most easily bonded with an epoxy adhesive similar to the material being bonded. Urethanes, cyanoacrylates, and thermosetting acrylics have also been used when certain properties or processing parameters are required. 

Adhesives may include styrene, styrene/isoprene blends, vinyl alcohol, vinyl acetate, epoxy resins, acrylates, cyanoacrylates (superglue), ethylene/vinylacetate (hot-melt), polyurethanes, etc. [19]. 

Plastics Cyanoacrylate, epoxy resins, polyacrylates, phenolformaldehyde resins, polyurethane, rubber additives (thiuram, carbamates)... 

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