Silicone foam, also known as molded silicone, is a porous rubber structural product made of silicone rubber as a base material and produced by foaming.

 

　　With the continuous development and updating of foaming technology, but also because of its superior characteristics, the application areas are more and more extensive, such as sealing strips, cushioning pads, construction gaskets, vibration isolation materials, protective equipment and so on.

 

Principle of silicone foam

 

　　Foaming silicone rubber, the principle is to add foaming agent in the selected silicone rubber compound, under pressure state heating vulcanization silicone rubber foam, rubber expansion to form a sponge-like bubble structure. The main factors that determine and influence the structure of the bubble are the amount of gas generated by the blowing agent, the diffusion speed of the gas in the rubber, the viscosity of the rubber and the speed of vulcanization. To make better silicone foam products, the choice of foaming agent species and rubber vulcanization system is the key.

 

　　Silicone foam production process

 

　　Silicone foam needs to go through a series of production processes, processing technology, each link will have an impact on the finished silicone foam.

 

　　1, plasticizing (that is, the plasticity of the raw rubber refining. That is, no additives in the open refining machine refining. Let the rubber soften to melt into the cooperating agent (to prepare for mixing).

 

　　The essence of plastic refining of raw rubber is to break and destroy the macromolecular chain of rubber, improve the plasticity of rubber, and make the mixing and blending of the compound easier. In the production of foamed rubber products, raw rubber is fully plasticized, will make the rubber plasticity better, easier to make the bubble hole uniformity, low density, small shrinkage products.

 

2, mixing, that is, the plasticized rubber to add a variety of agents (additives) for refining.

 

Mixing process is a variety of agents in the raw rubber (or plasticizing rubber) in the process of uniform dispersion. As with the mixing of other polymer materials, in order to make the compatibilizer uniformly mixed in the raw rubber, must use the strong mechanical action of the refining machine. However, because the rubber compound has more components of cooperating agents, the morphological properties of cooperating agents vary greatly, and the influence of cooperating agents on the mixing process, the degree of dispersion, and the structure of the rubber compound is also very great, so the mixing process of rubber is relatively more complicated than that of other polymer materials.

 

The mixing process has a very important effect on the performance of the rubber material. Mixing is not good, the rubber will be uneven dispersion of compatibilizer, plasticity of the rubber is too high or too low, burning, frost and other phenomena, which will not only make the calendering, pressing, molding and vulcanization process can not be carried out normally, but also lead to the performance of the finished product degradation, and may even cause the product of the early end of life. Therefore, mixing is one of the important processes in rubber processing.

 

　　3、Parking

 

　　Rubber in the mixing is completed, must be placed for an appropriate period of time, so that a variety of additives in the mixing of rubber fully dispersed, rubber additives dispersed more evenly, the stability of the product size, the degree of smoothness of the surface, the degree of uniformity of the bubbles is also the better.

 

　　3、Temperature

 

　　Rubber foam is very sensitive to temperature, the same kind of rubber, foaming effect is not the same at different temperatures, because the foaming system and vulcanization system is sensitive to the temperature of different degrees, the system changes, the matching degree of difference, the effect is also different.

 

　　4, molding

 

　　Foamed rubber products subsequent processing and molding methods are extrusion molding, molding, plate molding, etc., in accordance with the required structure of the finished product, specifications, length, size, shape, hardness, color is different, as well as the special needs of the drawings, you can carry out non-standard personalized customization.