Cyanoacrylate adhesive test

Fischer AA (1985) Reactions to cyanoacrylate adhesives instant glue . Cutis 25 18-22 Tarvainen K (1995) Analysis of patients with allergic patch test reactions to a plastics and glue series. Contact Dermatitis 32 346-351... 

Anaerobic adhesives. Test nnethods for anaerobic adhesives nnay be obtained fronn the Ministry of Defence under DTD 5628 or from HMSO. Cyanoacryiate adhesives. Test methods for cyanoacrylate adhesives may be obtained from the Ministry of Defence under TS 468 and TS10168. 

The properties of cyanoacrylate adhesives have been discussed in detail in the previous sections of this chapter. The evaluation of these adhesives is complemented in this section by comparisons with other structural adhesives. A specific comparison has been made of cyanoacrylate adhesives with a two-part epoxy, EC 2216 B/A, and a two-part polyurethane, EC 3549 B/A, all sold by 3M. The substrates on which the adhesives were tested were aluminum, polystyrene, and chloroprene. The results for room temperature water immersion, 90°F/90% relative humidity, and 150°F oven aging are shown in Tables XVI and XVII. 

Electron Spectroscopy for Chemical Analysis. Bond strength in Newton (N) using lap shear test (see Fig. 14.2). An epoxide adhesive was used for PVF, PTFE, and ECTFE, a cyanoacrylate adhesive for PVDF. 

Best results were achieved in these trials [2] with a standard cyanoacrylate and the use of primer only produced a marginal increase in strength (Table 2.13). All the other adhesives tested gave medium to lower strengths (including the toughened cyanoacrylate). 

Most engineering adhesives will bond readily to thermoset polyesters - often achieving substrate failure on test pieces (Table 3.4). Roughening the surface is usually beneficial, especially with the faster-curing cyanoacrylate adhesives. 

Nitrile rubber is generally easy to bond with cyanoacrylates (Table 4.8) and the use of a primer is not normally necessary. Of the other adhesives tested, the two-part acrylics and the UV acrylics showed promising adhesion. 

After a dwell time of five seconds under the device, it can be seen in Figure 7.10 that the shear strength of the bond between the LPDE sample and cyanoacrylate adhesive increased 10-fold, and the shear strength of the bond between the LPDE sample and the light cure acrylic adhesive increased 40-fold. Subsequently, MIL-STD-883 Method 2011.7 was applied as a destructive bond pull test to evaluate bond strength and bond strength distribution of various surface contaminations after CO2 treatment. The apparatus used had an accuracy of 5% and performed at a 90° peel angle. 

Direct tensile adhesion test An aluminum stud is mounted on the surface of the coating using a cyanoacrylate adhesive and then pulled to determine debonding force. ASTM D 5179... 

An example of this improvement in toughness can be demonstrated by the addition of Vamac B-124, an ethylene/methyl acrylate copolymer from DuPont, to ethyl cyanoacrylate [24-26]. Three model instant adhesive formulations, a control without any polymeric additive (A), a formulation with poly(methyl methacrylate) (PMMA) (B), and a formulation with Vamac B-124 (C), are shown in Table 4. The formulation with PMMA, a thermoplastic which is added to modify viscosity, was included to determine if the addition of any polymer, not only rubbers, could improve the toughness properties of an alkyl cyanoacrylate instant adhesive. To demonstrate an improvement in toughness, the three formulations were tested for impact strength, 180° peel strength, and lapshear adhesive strength on steel specimens, before and after thermal exposure at 121°C. 

Low surface energy substrates, such as polyethylene or polypropylene, are generally difficult to bond with adhesives. However, cyanoacrylate-based adhesives can be effectively utilized to bond polyolefins with the use of the proper primer/activa-tor on the surface. Primer materials include tertiary aliphatic and aromatic amines, trialkyl ammonium carboxylate salts, tetraalkyl ammonium salts, phosphines, and organometallic compounds, which are initiators for alkyl cyanoacrylate polymerization [33-36]. The primer is applied as a dilute solution to the polyolefin surface, solvent is allowed to evaporate, and the specimens are assembled with a small amount of the adhesive. With the use of primers, adhesive strength can be so strong that substrate failure occurs during the course of the shear tests, as shown in Fig. 11. 

Because of the high resistance to chemicals, gluing is not possible with solvents but suitable cyanoacrylate, epoxy and polyurethane adhesives can be used leading to strengths significantly inferior to those of PPS. Preliminary tests are essential. 

Joining is possible with adhesives such as epoxies, cyanoacrylates, silicones. Surface treatments are very useful. Preliminary tests are essential. 

Addition of typical crosslinking agents,such as 20% diallyl phthalate, 10% ethylene glycol dimethacrylate, 1% maleic anhydride or 1% itaconic anhydride, to the isobutyl 2-cyanoacrylate so that after curing a more rigid,insoluble, hydrolytically stable polymeric adhesive might be formed,does not increase the strength of the dentin-poly(methyl methacrylate) joint. Perhaps the cross-linked adhesive possesses decreased resistance to the thermal shock encountered by the test specimens. 

Fabric Peel Test Samples were cut from a plain weave cotton fabric (306 g/m ). Samples measuring 2.5 x 8 cm were cut, submerged in phosphate buffer (pH = 7.2), and allowed to air dry for 25 min. MFC measuring 350 (J-L (used as a model for cyanoacrylate-based tissue adhesives) was spread over a 2.5 X 6 cm area of one fabric sample, and a mating sample was placed on top. A 1200-g weight was set on top of the specimen for 1 min. The specimen was then allowed to cure for 1 h. The unglued portion was gripped into an MTS MiniBionix (Model 858) and the force required to separate the films at a displacement rate of 5.0 cm/min was measured. The maximum load after the initial peak was used to calculate the peel force of the adhesive joint. ... 

A fuse manufacturer replaced a 30 min epoxy used in a heat cure process to assemble stainless steel inserts into phenolic holders. By utilizing an aerobic adhesive bonding process, the assembly was complete in 30 s at room temperature. The resulting increase in productivity more than offset the higher adhesive cost. A cyanoacrylate bonding process was even faster, but did not resist aging in a moist atmospheric environment or pass a drop test for impact resistance. 

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