Causes and solutions for the generation of bubbles in the vulcanization of rubber products

1. There are many impurities in the vulcanizing agent, and the impurities of the small molecules become decomposed in advance, and the bubbles remain in the product.

2. The dispersion in the mixing rubber is uneven during the mixing.

3, the mixing temperature is low, there is moisture, the water volatilization is not clean, when the temperature is high, the sulfur is easily melted when the rubber is added to the open mill, or scorch occurs.

4. If the rubber material is not parked for a long time or is not parked, it will be used.

5. The rubber material is not uniformly heated, and the surface is not smooth when it is out.

7. When the rubber is heated on the open mill, the surface is covered with air, and the type of rubber has a phenomenon of harboring air.

8, not fully vulcanized, uncooked looks like bubbles.

9. The temperature of the mill roll, the temperature of the hot-melt glue, the temperature of the extrusion glue are not strict, and there are bubbles on the surface of the semi-finished parts.

Solution:

1. Optimize the production formula, select the easy-distribution additive to replace the auxiliaries used now, increase the application of processing aids such as dispersant and homogenizer, and improve the dispersion performance of various additives.

2. The mixing rubber is produced by the two-stage process of the internal mixer. When the mixing is carried out, the temperature is increased, and the moisture and volatile matter in the raw material are fully volatilized. The rubber compound is parked and then mixed in two stages. The temperature is controlled by adding sulfur. Within the accelerator temperature range, avoid scorch time or burnt.

3. Mastication, one-stage mixing, two-stage mixing, and out-of-type processes strictly control the parking time of semi-finished products. Allowing the various additives to fully diffuse, improve the uniformity of the rubber compound, and at the same time facilitate the recovery of stress and strain under mechanical action.

4, the rubber material should be evenly heated, through the knife, the tray, the silicone and other operations to make the rubber compound evenly. The operation method of separating the heat and the rubber and the output is adopted to improve the smoothness of the surface of the rubber compound.

5. The extrusion process is used to extrude the rubber compound, and the surface of the molding compound no longer has air entrapment.