Effect of selection of vulcanizing medium on rubber sheet

In the process of vulcanizing a rubber sheet, the vulcanizing medium is a heat transfer medium, so the vulcanizing medium needs to have good heat transfer dispersibility and strong heat storage capacity. Common vulcanizing media include water, air, steam, and other solid media, which are commonly used in the production of rubber sheets and rubber floors.

1. Saturated steam is currently the most widely used vulcanization medium. Its heat comes from the latent heat of vaporization. It has the characteristics of a large heating coefficient, high thermal conductivity, large heat release, convenient operation, and low cost. Saturation and steam are used as the medium for vulcanization, which can exhaust the air in the container and reduce the damaging effect of oxygen on the rubber in the air. The disadvantage is that it is easy to generate condensed water, the temperature is not uniform in the large vulcanization tank, and the local temperature is low.

2. Superheated steam method. Saturated steam is heated to form superheated steam. Because the superheated steam has less condensed water and the temperature in the tank is not subject to pressure, it is suitable as a medium with a high vulcanization temperature. However, this method will cause severe corrosion of the equipment.

3. Hot air vulcanization method. This method can be performed under normal pressure or pressure, and the heating temperature is not affected by pressure, contains no moisture, and is very dry. Products made by the hot air vulcanization method have a smooth surface and good appearance quality. For some special rubbers, such as polyurethane rubber, it is easy to hydrolyze, and hot air vulcanization is required. The disadvantages of this method are the small heating coefficient, low heat transfer efficiency, long vulcanization time, and the product is easily oxidized under high-temperature conditions.