Super light high elastic Environment-friendly EVA foaming material preparation

The specific problems are as follows: firstly, the decomposition temperature of a chemical foaming agent is required to be above the temperature at which EVA is close to melting by an EVA chemical foaming process, and the decomposition temperature of the chemical foaming agent is very wide and the decomposition process involves chemical balance, so that the chemical foaming agent still remains in a large amount in a material matrix after foaming is finished, measures of refining the low-temperature EVA in an unmelted state and increasing the addition of a series of auxiliary agents such as a cross-linking agent, stearic acid, a cross-linking initiator, a chemical foaming agent decomposition catalyst, a plasticizer and the like are mainly adopted in the industry for reducing the influence of the residual foaming agent on the foaming performance of the material, but the measures directly cause a large amount of micromolecular auxiliary agents easy to migrate in a final product, and the auxiliary agents continuously migrate to the surface of the product from the inside along with long-time use, so that skin infection or other pollution contacted with the product is caused; secondly, in the chemical foaming process, the decomposition of the chemical blowing agent determining the foaming behavior and the chemical crosslinking determining the melt rheology behavior proceed simultaneously, and the temperature suitable for the decomposition of the chemical blowing agent is not the temperature most suitable for the melt rheology for cell nucleation and growth. In addition, the chemical foaming agent and the chemical crosslinking are dynamic processes that are continuously performed with time, and the temperature dependence is very strong. The process for preparing EVA foam by the chemical foaming method needs to consider crosslinking and foaming at the same time so that the optimization of cell structure is difficult.

In order to solve the above problems, material manufacturers have been actively conducting exploration and study. the combination of EVA foamed material and other elastomer materials has become hot research among shoe manufacturers.