Nylon (commonly known as nylon) shrinks quickly and melts into a white gel when it is close to the flame. It melts and drips in the flame and produces small bubbles. There is almost no flame when it burns, and it is blue. It will stop burning when it leaves the flame. Self-extinguishing, giving off an amino or celery smell, it is a hard and black bead-shaped melt after cooling and is not easy to grind with fingers. Polyester will melt and shrink when it is close to the flame, it will melt in the flame, and there will be a yellow flame when it burns. It is a dark brown lump, which can be crushed with fingers. The pp webbing (polypropylene webbing) melts and shrinks when it is close to the flame. It will melt when it burns in the flame, and a flame will appear. The upper end of the flame is yellow, and the lower end is blue. It will continue to burn when it leaves the fire, and it will emit a paraffin smell. After burning, it will be ashes It is light yellow-brown granules, which can be crushed with fingers.
Nylon feels comfortable, smooth and soft. It can be loosened after being squeezed tightly by hand. There are creases, which will slowly recover. Scratch with nails, and there is no obvious scratch. Polyester feels a little rough, and there are wrinkles after being pinched and loosened by hand, there are still some creases after being flattened, and there are obvious scratches after scraping with fingernails. Compared with nylon and polyester, the feel of pp webbing is rough, the color of webbing is relatively dull, and the yarn is relatively thick.
3. Buoyancy: Cut the yarn a little, twist the yarn into a ball, put it in the water, after the water is soaked, the pp polypropylene floats on the water, and the nylon or polyester sinks.
4. Dyeing: Nylon webbing is dyed after the webbing. After cutting, the yarn is white due to uneven dyeing.