Rubber abrasion resistance tests

Four standard rubbers are specified, two of which are the same as those given in ISO 4649. The other two are a high abrasion resistant SBR compound and a low abrasion resistant material which may be preferred for comparison with high and low abrasion resistant test materials respectively. For all three methods, the calculation of abrasion resistance index is specified. 

A type of test for determining abrasion resistance. Fixed knives, under constant load, scrape across a rotating rubber test piece. The resulting loss in weight is a measure of the abrasion resistance. 

ISO 3934 2002 Rubber, vulcanized and thermoplastic - Preformed gaskets used in buildings - Classification, specifications and test methods ISO 4649 2002 Rubber, vulcanized or thermoplastic - Determination of abrasion resistance using a rotating cylindrical drum device ISO 4664-1 2005 Rubber, vulcanized or thermoplastic - Determination of dynamic properties - Part 1 General guidance... 

An example of how this technique may be beneficial is taken from Paris Short Course in Statistical Methods. The chemist wanted to know if chlorination would affect the abrasion resistance of a particular type of rubber. He selected ten pieces of rubber for the test, and chlorinated one-half of each piece, leaving the other half as it was. Abrasion resistance results were obtained on the twenty pieces. 

Neoprene is the generic name for polychloroprene rubber. It has been produced commercially since 1931 and had rapid and wide acceptance because it is much superior to natural rubber for heat and oil resistance. Heat resistance is far better than NR, BR or SBR. but less than EPDM. When heated in the absence of air, neoprene withstands degradation better than other elastomers which are normally considered more heat resistant, and retains its properties fifteen times longer than in the presence of air. Compression set at higher temperature is better than natural rubber and 100°C is typically the test temperature rather than 70°C. Abrasion resistance is not as good as natural rubber but generally better than most heat resistant and oil resistant rubbers. This is also true for tear strength and flex resistance. 

Abrasion resistance is the reciprocal of volume loss. If the volume loss or abrasion resistance only is quoted, it is desirable to have some certification of the abradant used. This is naturally supplied to some extent by specifying a particular grade and source of supply but leaves open to question the variability of that source of supply. Some workers prefer to use a standard rubber to test the abradant and to calculate a relative volume loss ... 

In researching resistance on rubber abrasion, a Martindale tester is used for com-parasions of various rubber samples. Five types of rubbers have been tested in five cycles on four tester positions. Design of experiment for five rubber types and five test cycles is the Youdens square shown in Table 2.85... 

The Taber abrader test for abrasion resistance of the mastic shows that the mastic has an abrasion resistance of rubber tile and unprinted linoleum. 

ASTM D1630 Standard test method for rubber property-abrasion resistance (footwear abrader)... 

Figs. 11 to 13 illustrate the temperature dependence of strain at failure (in bending test), change in surface roughness with additional traffic exposure period, and skid resistance of the asphalt mixtures using powdered rubbers, respectively. The advantages of the asphalt mixtures are improvements in skid resistance and abrasion resistance, a reduction in traffic noise and a prevention effect of freezing. 

There could be numerous uses for the recovered carbon black for rubber goods such as vehicle tires, footwear, rubber sheets, conveyer belts, dockfenders, etc. Some samples of rubber goods such as bicycle tires and safety shoes have been made with the recovered carbon black and their durability has been tested in comparison with commercial ones. At least in short term tests, for example, three months, the safety shoes made with the recovered carbon black showed higher abrasion resistance than the commercial shoes in which HAF-LS carbon black was used. The test results are shown in Table IV (6). 

Several performance characteristics of rubber such as abrasion resistance, pendulum rebound, Mooney viscosity, modulus, Taber die swell, and rheological properties can be modeled by Eq 7.34. " A complex mathematical model, called links-nodes-blobs was also developed and experimentally tested to express the properties of a filled rubber network system. Blobs are the filler aggregates, nodes are crosslinks and links are interconnecting chains. The model not only allows for... 

Wear is important in applications as diverse as tires, conveyor belting, footwear, and windscreen wiper blades, yet most of us would accept that the rubber industry still awaits a laboratory test or series of tests that can predict service performance with any confidence. Over the years, there certainly has been no shortage of small-scale tests for abrasion resistance and indeed no shortage of claims or reports of satisfactory correlation with the behavior of various products, but strong doubts remain, and some sectors, not least the tire industry, conclude that there is no substitute for a service trial or a simulated product test, for example, a road trial on tires held at a small slip angle to accelerate wear. 

The Lambda series of Medicaflex is a polyurethane-based TPE polymer that exhibits low modulus characteristics with high tear strength and abrasion resistance. Those listed in the tables have passed USP Class VI compatibility tests and have been used as replacements in some natural rubber latex and silicone rubber applications. The polymer has been applied to uses such as catheters, tubing and films where softness, low durometer hardness, low modulus or high elongation are needed (Tables 4.3, 4.12, and 4.13). 

D 1630 Test Method for Rubber Property - Abrasion Resistance (NBS Abrader)... 

Abrasion Resistance. Abrasion is the wearing of material from a rubber surface due to the action of an abrasive surface in contact with and moving with respect to the rubber surface. It is measured under a specified load, at a specified sp d and type of abrasive surface. Laboratory tests may not predict service life, because the many and complex factors affecting abrasion vary greatly from application to application. However, laboratory tests are useful for quality control of rubber products intended for rough service. 

Pal et tested the abrasion resistance of NR/XNBR vulcanizate for various rubber weight ratios and CB grades. The weight ratio of 80/20 for NR/ XNBR blends combined with a relatively low CB particle size was found to deliver the best abrasion resistance. 

Abrasion resistance has not been discussed here, but it is an important factor in performance. In limited field testing on another series of promising polyurethanes, the unfilled polyurethanes abrade at a rapid rate compared to compounded rubbers. The excellent abrasion resistance frequently shown by polyurethanes in conventional tests does not occur in field tests where the samples are track pads for tanks. 

The abrasion resistance of a rubber has been related to the ability of a rubber to undergo rapid deformation. In turn this is a function of segment flexibility which increases with an increase in the difference between the Tg and the test temperature. Since the TgS of the polybutadienes are low the abrasion resistance of polybutadiene vulcanizates is, as may be expected, good in comparison to other elastomers. 

The most widely used test to rate the abrasion resistance of plastics is the Taber Abrasor (6). te this test, a 10 cm square plaque of the plastic is affixed to a record player type of turntable. As it rotates in the horizontal plane, two weighted rubber/abrasive wheels counter-rotate on the plaque to produce a circular wear... 

The abrasion resistance of plastics can also be determined by the ASTM G 65 dry sand rubber wheel test (7), vriiich is shown schematically in Figure 2. The three-body abrasion produced by this type of test is simitar to that produced by rubbing plastic on a rigid surface with hard particles in the faying surface, but it is probably faster and easier to perform. Test times can be as short as one minute. This test can also be conduct immersed in a slurry (8) if this better simulates the system of interest. 

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