Tear resistance, paper testing

All application verification and soil samples must be individually labeled with unique sample identification (ID) and other identifying information such as study ID, test substance name, sample depth, replicate, subplot and date of collection, as appropriate. Proper study documentation requires that sample lists and labels be created prior to work commencing in the field. Water- and tear-resistant labels should be used since standard paper labels may become water-soaked and easily torn during sample handling. Sample lists should have the same information on them as the labels and are a convenient place to record plot randomization, initials of the individual who collected the sample, and date of collection. As such, the sample list is important in establishing chain of custody from the point of sample collection until its arrival at the laboratory. 

Matched sets of folding endurance and tear resistance test specimens were prepared from each paper to be aged at several temperatures. Aging was done in forced circulation ovens that were supplied with air having a dewpoint of 53°F. At intervals, sets of test specimens were removed from the oven and tested to monitor the deterioration process. 

Testing of plastic films - Tear test using trapezoidal test specimen with incision Testing of paper - Determination of tearing resistance according to Elmendorf (single tear tester)(withdrawn replaced by ISO 1974 2012)... 

Instron tensile tester n. A high precision electronic test instrument designed for testing a variety of material under a broad range of test conditions. It is used to measure and chart the load-elongation properties of fibers, yarns, fabrics, webbings, plastics, films, rubber, leather, paper, etc. It may also be used to measure such properties as tear resistance and resistance to compression. 

The fact that the correlation equation contains a constant can be explained by considering the action of the two testing machines. The constant strain machine records only the maximum force exerted on the specimen. For flexure tests, this is usually the point where the core first cracks. Additional resistance to breaking occurs as the paper tears and in the case of a board containing glass fiber, as the fibers pull out of the core. The force required for this second break may even exceed that for the initial core crack. 

Consideration of what is done to the core when conducting the two tests indicates that they are somewhat similar. True, the pin used for the nail pull resistance test has a larger diameter and must tear through the paper before it crushes the core, but the basic action is to crush the core by pushing a pin into it. 

There is an almost unlimited number of ways to characterize spunbonded fabrics. Many tests in use were originally developed for the characterization of textiles and paper products. When taken together, properties such as tensile, tear, and burst strength toughness elongation to break basis weight thickness air porosity dimensional stability and resistance to heat and chemicals are often... 

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