It is said that TPE or TPR products will crack, so what exactly makes TPE (TPR) products crack? Analyze when what happens when TPE products will crack.

　　I. Weather reason

　　Low temperature, TPE material (rubber phase) microstructure molecular arrangement will change, the relative slip of molecules becomes difficult, or the tensile performance will become poor. Suction cups in the process of use, by the external force, the lower hardness part of the TPE pieces of stretching, but because of the low temperature, the stretching will become poor, more than the limits of the material can withstand, resulting in the products fracture (cracking).

　　II. Material strength

　　The problem of tensile properties mentioned above is that the low temperature tensile deformation resistance of the material decreases, which leads to the cracking of the product. Then if we can use the base material which can maintain the tensile property at low temperature, the problem will be solved.

　　To sum up, the external reason for the cracking of the suction cup product is the cold weather, while the internal reason is the change of molecular arrangement of the material and the deterioration of the tensile property. The combination of external and internal causes leads to the cracking of TPE suction cups.

　　The above is only the analysis of the causes of TPE/TPR products cracking from the case of suction cup products cracking.

　　Third, other reasons

　　In fact, there are some other reasons for the cracking of TPE/TPR products, which should be analyzed according to the material characteristics and actual processing conditions.

　　1. SBS base material of TPR aging resistance is poor, prone to aging cracking;

　　Solution: It is recommended to change the SEBS base material TPE.

　　2. SBS base material of TPR shoes, in the process of brushing glue, if there is a crack (cracking), it may be due to glue corrosion;

　　Solution: should pay attention to the glue try not to brush too much, do not condense in one piece.

　　3. Some low hardness size thick TPE products, may be due to injection molding process pressure retention is not enough, the occurrence of stress shrinkage, serious cracking phenomenon will occur.

　　Solution: The molding pressure should be strengthened to eliminate stress shrinkage.