After TPE/TPR materials are processed into products, sometimes there will be products spitting oil|oil analysis (the surface is sticky, and even a layer of oil can be directly wiped out to the hands). This situation, according to the different material mixing system, there may be two different factors, the analysis is as follows.

　　1.TPE|/TPR blending system (lower hardness 0 ~ 20A) oil locking and oil absorption problems

　　General SEBS-based TPE|TPR than SBS-based TPR has a more excellent oil absorption (oil absorption rate). As for SEBS, the oil absorption and oil locking properties of SEBS grades vary with different physical properties (such as butadiene content and different molecular chain structures). Choosing SEBS, especially the SEBS grade with good oil locking property, and choosing the right type of operating oil will reduce the problem of oil spitting on the surface of TPE materials, especially the lower hardness TPE materials (usually the lower hardness TPE materials will be matched with more proportion of operating oil, and the chance of oil precipitation is higher).

　　2.TPE/TPR blending system (higher hardness above 90A) oil precipitation

　　Higher hardness of TPE, especially the SEBS base system of TPE, because the rubber SEBS content in the blending system is relatively reduced, which leads to TPE blending material oil absorption is small, if the blending system to add oil more than a certain limit, it is easy to precipitate out. For some larger size, thinner high hardness TPE products, the possibility of this surface oil spitting problem will be greater.

　　In short, TPE/TPR products surface spitting oil, is basically a problem of TPE, TPR materials, and the user production and processing process is not related. As far as the material is concerned, there are the following three factors

　　First, SBS, SEBS base material and characteristics.

　　Second, the type and characteristics of the operating oil.

　　The third is the process control of TPE/TPR granulation process.