Seal strength test

Figure 9-01. Heat-seal strength DuPont Surlyn 1601 (DuPont heat-seal strength test).f ...

Preliminary tests of using this system as a seal between copper and polyimide showed that a seal strength up to 4.2 N cm could be obtained with systems containing 70 mol% phenyl silane, 27.5 mol% methyl vinyl silane and 2.5 mol% EOS. Fracture investigations show that a cohesion rupture is also dominating in this case, confirming the above mentioned result that the brittleness of the seal is too high. 

This provides the details needed to complete the design of the screening experiment. It was decided to run a screening experiment with the 22 trials shown in Table 1. For each of the 22 trials, the process is set to the specified conditions, and time is allowed for the machine to reach the set conditions and then a series of units are produced. For each trial, five units were randomly selected and tested for seal strength and 50 units were inspected for burns. The resulting data is summarized in Table 1. For each trial, the average and standard deviation of the five units is shown along with the number of units with burns. 

The sealing strength of petroleum wax is determined in a test (ASTM D2005) in which two paper specimens, 5x10 in., are cut and sealed together by passing them over a heated bar. The sealed papers are conditioned at... 

Figure 19- Relationship between d-limonene content and seal strength for the test films.

Stability testing for intrauterine devices (IUDs) should include the following tests deflection of horizontal arms or other parts of the frame if it is not a T-shaped device (frame memory), tensile strength of the withdrawal string, integrity of the package (i.e., seal strength of the pouch), and sterility of the device. 

Ultimate Seal Strength Maximum foree that a heat-sealed fliermoplastie film ean sustain in a tensile test without seal failure per unit length of the seal. 

Various film compositions of COC added to PP, HOPE, and LLDPE were tested by the company under retort conditions. Researchers found that the COC improved pouch seal strength and vapor transmission rate, with only slight losses in tear resistance. And after retort treatments, the COC content reportedly improved film stiffness, without causing other negative changes to properties or appearance... 

Heat-seal strength n. With heat-sealed flexible films, the force required to pull apart a heat-sealed joint divided by the joined area tested. The strength of a heat seal is sometimes expressed as a percentage of the film s tear strength or tensile strength. 

American Society for Testing and Materials 1434. Standard methods of test for seal strength of flexible barrier materials, ASTM 68-88. Philadelphia (1973). 

The tensile properties of the monolayer and the multilayer film were tested using an Instron 4400R following ASTM D-882 while the seal strength properties followed ASTM F-88. 

The tensile properties of the monolayer film before and after retort were tested and compared. Young s modulus increased by 18% and toughness increased by 32% for the cast film samples after retort. The seal strength of the monolayer films was tested before and after retort to determine how the retort process affected the seal strength, however the change in seal strength was negligible. 

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