Date:2019/5/21 16:02:02 Number of visits:
A few warp and weft yarns of two kinds of unknown webbing are separated by the elastic tape for edge wrapping. They are respectively burned with a lighter. Some physical phenomena are observed during the burning process to determine the raw materials of warp and weft yarns. During the burning of the edge elastic belt in chengde, the flame, melting condition, smell and ash after burning should be observed respectively.
Nylon webbing: near flame is melting and burning, dripping and bubbling, not direct continuous burning, like celery taste hard, round, light, brown to gray, beaded.
Polyester ribbon: melting and burning near flame, dripping and foaming, can be continued burning, a few smoke very weak sweet, hard round, black or light brown.
