(1) Take four spandex samples, remove the surface layer, and then take three paragraphs with a length of 10cm, and mark the distance with a color pen.

(2) Join the head and tail of the sample, put it on a single-yarn strength machine for testing, and stretch at a speed of 50cm/min.

SMS+PE

(3) First, stretch the sample by 100%, 150%, 200%, 250%, and 300% for 3 times, and then calculate the tensile stress (cn) and elastic recovery rate for the fourth time. Elastic recovery rate %=(10cm-test length)/10 X 100%.

Conclusion: Different products have different elastic requirements for spandex, some products require low elongation, high elasticity or high elongation, low elasticity or low elongation, low elasticity or high elongation, high elasticity for spandex, so different fabrics It is necessary to choose different suitable spandex. The standard rate is compared with other brands by 300% data to ensure the same quality of spandex used by enterprises.