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What are the risks of runway effect of plastic flow?
The "poisonous runway" will have an accident when it is hot, and inferior materials will release toxic gases under strong light and high temperature. Causes students to have nosebleeds, coughs and skin allergies.

At present, polyurethane racetrack is generally TDI type, and its glue component A is a prepolymer formed by the reaction of polyether and TDI. If the reaction is not sufficient, there will be free TDI, which is harmful to human body. TDI is listed as a chemical substance with high occupational hazards by the state, which is a toxic carcinogen and irritating to eyes, respiratory tract and skin.

In addition to free TDI, some plasticizers used in polyurethane glue, such as short-chain chlorinated paraffin, will decompose chlorides such as volatile hydrogen chloride gas and toxic organic solvents (toluene, xylene) used in the laying process in the sun. Generally, these three things cause the problem runway to have a choking smell.

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Plastic runways can be roughly divided into two categories: polyurethane cast-in-place and prefabricated rubber coils. Precast type mainly uses raw materials such as rubber, which is an environmentally friendly product, but it is not popular in China because of its high cost. Polyurethane accounts for 95% of the current domestic market. At present, the runways and playgrounds that have problems are of this type.

The basic raw material is polyurethane two-component (A, B) glue. During construction, two kinds of glue A and B are mixed according to a certain proportion, black particles are added, and solvents are also used during laying. Because the two-component glue, black particles and solvents used involve a variety of chemical materials, almost every part has the possibility of problems.