Fabric peel test

Schematic depicting cotton fabric peel test.

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. ... 

The results in Table 5.3 led to the conclusion that the fabric peel test (FPT) method is reproducible and provides lower variability as compared to the other two methods. Accordingly, this method was optimized in terms of curing time of V-200 (a PTOEO/MPC formulation) and adopted as an in-house standard test method. The peel force was recorded as the maximum load-to-fail in N for a sample width of 1 m. During optimization, a 15-min cure time was selected on the basis of data in Table 5.4. Typical results on absorbable and nonabsorbable formulations using the optimized FPT are summarized in Table 5.5. The peel force was recorded as the maximum load-to-fail in N, normalized to a sample width of 2.5 cm. 

Peel Force Data of V-200 Adhesive Formulation as Measured by the Cotton Fabric Peel Test... 

Adhesion to moist substrate (using the fabric peel test cited in Chapter 5)... 

Coating with Bulk Polybutadiene. E-glass fabric was embedded In Firestone s Diene 35 NFA using procedures very similar to those used to prepare peel test specimens. Rubber, which had been mill-mixed with 0.05% dlcumyl peroxide, was premolded between Mylar sheets to the desired thlckness(0.308, 0.151, or 0.100 cm) and size ( 30.5 X 18 cm) by molding for 1 hour at 60 C. and 40,000 lbs/5" ram. Fabric was cut so that the final size was at least one Inch smaller than the rubber sheets In all directions. A sandwich was made from the fabric and two premolded rubber sheets of the same thickness and about half the total thickness of the final sandwich. The sandwich was cured In a press for 2 hours at 150°C and 5000 lbs/5" ram. In the cured specimen the fabric was embedded In the center of the molded specimen (0.15 -0.40 In thick). Samples were Immensed In alkali before cutting to size for tensile tests. 

Borroff and Wake48, and later Meardon49, developed a direct tension method which was claimed to more nearly measure the true adhesion between fabric and rubber. It is particularly useful for discriminating between adhesive systems, when the peel tests can be misleading. The main objection to the method is practical in that the preparation of test pieces is rather difficult. 

Test Method Coat Tensile Test on Incision Nylon T Type Peel Test Fabric T Type Peel Test... 

Tests for adhesion are carried diit in peel or direct tension, peel being the most common, although tension tests are particularly useful for thin coatings where the rubber is too thin or too weak to carry out a peel test successfully. Tests have been standardized in the rubber industry, where the aim was probably at such products as belting, and also in the coated fabric industry. 

On the whole, the peel strength and rubber coverage on the treated Technora fabric samples after peel tests were rdkitively high, and were less dependent on the nylon type. 

Figure 11 Rubber coverage after peel test of plasma treated and nylon ion-plated PPTA fabric samples coaled with RFL to rubber.

Peel test Assuming the strain in the tab is negligible (e.g. if (1) the peel forces are very low or (2) a fabric- or plastic-backed rubbery adhesive or a relatively thick metallic substrate is the peeling member) and plastic bending of the tab does not occur, then adhesive fracture energy (critical strain energy release rate) is given by... 

In ASTM D1876-72, or the T-peel test, the test specimens have a simple configuration and are easily fabricated. Two flexible adherends, one inch... 

Results shown in Figure 8.13 show the superior adhesion characteristics obtained with the Saret 633 when cured against the fabric at 160 °C for 20 minutes. Fabric was peeled from the rubber at an angle of 180. Failure mode was cohesive with rubber remaining on the fabric after the peel test. 

Another similar test is the peel test [11]. A strip of self-adhesive material is peeled off the substrate and the force needed for peeling is recorded. In order not to tear the rubber during the peeling test it is reinforced with a glass fabric. 

After drying and re-weighing, the adhesive coated fabric was placed between the two pads of rubber. This assembly was then vulcanized in a compression mold (same as used for ASTMD429-B). After vulcanization (e.g., 30 at 307°F) the sandwiched pad was cooled and 1" wide specimens were cut for peel testing. 

Because coated fabrics are generally dealt with in separate standards committees, and because the thinner coatings are not strong enough to allow the use of the peel methods described above, separate standards have been developed for these products. The problem of failure in the coating is overcome by using reinforcements of fabric or cement. These methods are really product tests and outside the scope of this book but the appropriate references can be noted. The international standard for coated fabrics is ISO 241144, the British methods are identical as BS EN ISO 2411 and the ASTM methods are in D75145. There are also methods for conveyor belts in ISO 252-146. 

BS 903 Part A4858 is identical to ISO 4647 and Part A 5659 identical to ISO 5603. It is significant that the equivalent ASTM standards are not produced under the auspices of the committee for rubber but in a subcommittee of the textiles committee specifically covering tyre cord and fabrics. The H-test is in D477660 and the method for steel cord in D222961. There is also a method for strap peel adhesion test of reinforcing cords or fabric in D439362. 

ASTM D4393, 2004. Standard test method for strap peel adhesion of reinforcing cords or fabrics to rubber compounds. 

After the surface layer of the leather sample is peeled off, the sample can be observed under a microscope. The collagen fibres of leather differ in appearance from non-woven fabrics and from the uniform polymers of coating and lamination in the synthetic substitutes. However, some artificial leathers in the market do better than the real leather. It has been reported that some leather substitutes with super-microfibres of nylon, polyester and polypropylene can have similar views of cross-section under the microscope (Cheng, 1998). A combination of the bum test, the chemical test, the infrared spectroscopic analysis and/or the microscopic... 

---