The above is to find out the materials of webbed bags and waterproof backpacks on some e-commerce platforms, which are called tarpaulins. In fact, they are chemical fiber bonded PVC materials, or PVC mesh or PVC bonded fabrics.

Why not call it PVC fitting or PVC clip net directly? This is a cover up. It is directly called PVC related names, which will make people feel that it is a low-grade material. After all, the EU has strict restrictions on the application of PVC, which belongs to non environmental protection materials and has great pollution to the earth and nature.

Interpretation of physicochemical properties of PVC materials

PVC material has low cost and environmental protection, and its physical and chemical properties are not very friendly. It has peculiar smell, strong taste, poor hand feel and sticky. Low melting point, easy to melt and deform in hot weather, hard and brittle in cold weather, with the risk of cracking and breaking. That is, the range of temperature difference is very small, which is easy to cause problems when used in polar environment. In addition, the color of PVC is easy to shift. If light PVC contacts with other dark objects for a long time, the dark color will be dyed to PVC. PVC resin with high purity begins to escape hydrogen chloride gas when it is above 100 ℃ for a long time or exposed to ultraviolet radiation. It shows that there are sharp groups or unstable structures in its molecular structure. The longer the time, the more degradation and the higher the temperature, the faster the degradation rate, and the faster the degradation rate in the presence of oxygen or air.

As a comparison, TPU material is too excellent. For example, it has high melting point, high cold resistance and a wide range of temperature difference suitable for use. It can be used in the environment of minus 25 degrees to more than 60 degrees of high humidity. TPU is also an environmental protection material. Some food grade TPU can even be used as drinking utensils. The EU's requirement for drinking water appliances is that PVC is generally prohibited, but TPU is not prohibited.

The following is the podragon flipper bag, which is made of TPU material

which is more excellent and environmentally friendly, feels better and has no peculiar smell.

40L large capacity, with an outer pocket for storing flipper frogs