Test, testing adhesion

Testing of Painted Products. The enhancement of paint adhesion is one of the principal functions of conversion coating (20—22). A group of tests based on product deformation is used to test the painted product. The appHance and cod-coating industries use the mandrel bend, the cross-hatch adhesion test, and the direct and reverse impact tests. Adhesion after a water soak is judged using a cross-hatch test performed on the exposed surface. 

We tested adhesion and proliferation of rat NSCs on surfaces with immobilized dEGF-His, EGF-K5-His, EGF-E5-His, or EGF-His. The surface with immobilized dEGF-His provided the highest efficiency for selective expansion of NSCs. On this substrate, cells expanded 60-fold over 96 h of culture. Of note, over 98% of the expanded cells expressed nestin, but not pill. 

Organic coatings are commonly evaluated using salt water immersion, salt fog or spray, modified salt exposure tests (e.g., salt fog with added SO2), and various cyclic exposure tests. Humidity exposure and water immersion, and, for many applications, physical resistance tests (adhesion, impact resistance, etc.) are widely used preliminary tests. Standard methods for most of these tests are given in compilations of standard tests such as the Annual Book of ASTM Standards (16). Test methods have been extensively reviewed (e.g., 17-23). 

FIGURE 13.9 Descriptions of simple tensile detachment (a) and simple lap shear (b) assemblies for testing adhesion. 

Table 2. Wet and recovered direct pull-ofT test adhesion strength values for aluminum/epoxy paint systems employing silane coupling agents 116...

Abstract—The effects of both y-aminopropyltriethoxysilane (APS) and elevated temperature and humidity (T H) exposure on the adhesion of pyromellitic dianhydride-oxydianiline polyimide to SiO , AkOi, and MgO were studied using XPS, SEM, and peel test. Adhesion and T H stability of PMDA-ODA on Si02 is significantly improved when APS is used at the interface, while no significant improvement is observed for AkO, or MgO. XPS analysis of the surfaces showed no retention of APS on AkO, or MgO, while Si02 did retain APS, as is expected. The APS retention is affected by surface treatment of the oxide prior to APS application. 

Fig. 3.14 Basic types of models for testing adhesives (a) end-to-end skin flap, and (b) end-to-end blood vessel...

Figure 6.44 Chromatograms from the LC/UV/ion trap MS analysis of leachables that were extracted from a test adhesive with deionized water at 50°C for 3 days. (A) UV chromatogram at 220nm. (B) TIC full-scan MS chromatogram. (Reprinted with permission from Tiller et al., 1997a. Copyright 1997 John Wiley Sons.)...

Anderson, G. P., et al., Effect of Removing Eccentricity from Button Tensile Adhesive Tests, Adhesively Bonded Joints Testing, Analysis, and Design, ASTM STP 981, W. S. Johnson, ed., American Society of Testing and Materials, Conshohocken, PA, 1988. 

How to Test Adhesive Properties, Materials Engineering, March 1972, pp. 60-64. 

D 1304 Methods of Testing Adhesives Relative to Their Use as Electrical Insulation... 

When subject to 90° peel test, adhesion values of 7-10 lbs/in have been obtained under ambient conditions. Interestingly, the adhesion after the solder float test retained 4-6 lbs/in. This high adhesion is believed to be primarily due to the mechanical interlocking facilitated by the textured Kapton polyimide. 

Ohama, Y., Demura, K., Nagao, H., and Ogi, T., Adhesion of Polymer- Modified Mortars to Ordinary Cement Mortar by Different Test Adhesion between Polymers and Concrete Bonding,... 

The universally aeeepted method for testing adhesion under shear is a static load test [21], where a known surfaee area of the adhesive-coated product is applied under controlled... 

In this ehapter we describe the chemistry and technology of polysulfide polymers processing and manufacture of polysulfide sealants and adhesives, including their formulations curing reactions and characterization and testing. Adhesion considerations are also discussed briefly. 

Wire and component tacking with UV curing aerobic acrylic adhesives has been adopted by a manufacturer of flight systems boards where the need was to tack numerous wires and components in place and reduce manufacturing costs at the same time. Two populated boards with fluorocarbon insulated wires, soldered in various configurations, were bonded in this test. Adhesives being compared were exposed to various mil-standard specifications for humidity, immersion, temperature, and Humiseal coating. 

Testing adhesive, detail and substrate separately or bonded to a worst case substrate... 

The vast majority of fibrillar adhesive materials have been prepared to (1) test adhesion model prediaions or (2) explore and optimize attachment to dry surfaces. Nevertheless, in order to expand the range of applications for synthetic fibrillar adhesives, it is desirable to improve performance under humid and wet conditions. For example, compared to flat and unstmc-tured polyvinylsiloxane, generating microscale mushroom fibrillar architectures with this material improved adhesion to both hydrophilic and hydrophobic surfaces under water. ... 

Figure 23. Specimens with possible thermal degradation of the adhesive layers after the delamination tests adhesive no. 037 (left) and 052 (right).

The adhesion at substrate/PU interfaces was measured by lap-shear and by constrained blister test methods [11, 12]. For lap-shear testing, adhesives were mixed with glass beads. Class 4A from Ferro Microbeads, and deposited on PVC and Xenoy substrates to yield dry films 0.35 mm thick. The adhesives were cured by exposure of 3 days at room temperature and 50% relative humidity, followed by 4 days at 50 °C, 0% relative hmnidity. The lap-shear specimen arrangement si shown in Figure 7.7a. All determinations were... 

Figure 4.1. Experiment to test adhesion of steel blocks polish blocks, wiring together, apply...

It is evident that a large number of parameters are involved in the fabrication and testing of bulk adhesive specimens and adhesive joints these must be controlled if meaningful experimental data are to be obtained. Joint tests evaluate not only the mechanical properties of the adhesive, but also the degree of adhesion and the effectiveness of surface treatments. The standard test procedures listed by ASTM, BSI, DIN and other official bodies are essentially for testing adhesives and surface treatments rather than joints (e.g. Table 4.3). Unfortunately, most of these tests consist of joints in which the adhesive stresses are far from uniform. The designer and the researcher therefore have to select appropriate tests, and to know what the results mean in terms of their own particular investigations and applications. 

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