Wet tensile strength of a sample is important to evaluate the mechanic performances subjected to moisture and stress during processing or use. It is particularly useful for measuring paper and other materials which are easily damaged by handling when wet.
The above testing instrument is from Thwing Albert. It consists of an open ended horizontal bar which simplifies insertion of the sample and a vertically movable container that holds water or other liquid. The sample is wrapped around the bar and both ends are secured in the upper grip. The operator raises the container to moisten the sample, and then the test is started. This device complies with TAPPI T456, ISO 3781 and ASTM D824. For how to do the test, the following video is very helpful.
Scientists found evidence to suggest that wet tensile strength is related to the removal efficiency for recycling compatible adhesives (RCA). link the References.