What are the reasons why rubber products spray frost?

Rubber product spray is a common problem in the rubber industry, it refers to the rubber formula of some organic small molecular compounds in the rubber product or semi-finished surface precipitation, forming a layer of exudate similar to frost. Spray not only affects the appearance of the product, but also may affect its performance. The following are the main reasons for rubber products to spray frost:

First, improper formula design

Improper formulation design is one of the important reasons for rubber products to spray frost. It mainly includes the following situations:

1. Saturated ejection: common in sulfur, accelerators, active agents, antioxidants, etc. These compounds have limited solubility in rubber and will precipitate out of the surface when the amount exceeds their solubility.

2. Migration ejection: common in processing AIDS, migration antioxidants, antistatic agents and so on. These auxiliaries have strong mobility in rubber and are easy to migrate to the rubber surface.

3. Generation and ejection: common in sulfur vulcanization system, accelerator and reaction products. These reaction products may have a lower solubility, resulting in frosting.

4. Reaction retention: common in organic peroxide vulcanization system, low molecular substance excess. The low molecular material does not react completely during the vulcanization process and will remain in the rubber, resulting in frost spraying.

5. Stress ejection: common in inorganic fillers, such as calcium carbonate. These fillers are unevenly distributed in rubber and are easy to precipitate under stress.

2. Improper process operation

Improper process operation is also a common cause of frost spraying of rubber products. It mainly includes:

1. Uneven mixing: During the mixing process, the compounding agent is not evenly dispersed in the rubber, resulting in excessive local compounding agent, which precipitates out of the surface.

2. Mixing temperature is too high: too high mixing temperature will cause local excess of the compounding agent, resulting in frost spraying.

3. Inaccurate weighing: more weighing, less weighing, missing weighing, misweighing, will lead to local spraying of rubber products.

4, vulcanization temperature is too high or too low: vulcanization temperature is too high will lead to polymer degradation, vulcanization temperature is too low will lead to incomplete reaction, will lead to frost spray.

5. Insufficient curing time: insufficient curing time will lead to less sulfur spray.

6. Improper operation of spraying release agent or washing water: these operations may lead to white rubber surface phenomenon, similar to spraying frost.

3. Fluctuation of raw material quality

Fluctuations in the quality of raw materials are also one of the reasons for the spray of rubber products. Different origin, different manufacturing methods, different processes of raw materials are very different, raw rubber synthesis process (such as polymerization temperature, catalyst, synthetic monomer, etc.) differences will cause different solubility. In addition, changes in raw material purity, moisture, ash, pH, physical properties, etc., may also lead to frost spraying.

Fourth, poor storage conditions

Rubber products in the storage process, if the temperature, humidity, pressure and other conditions are improper, may also lead to frost. For example, the solubility of the compound in the rubber rises and falls with the temperature, and if the storage temperature is too high, the solubility of the compound is reduced and it is easy to precipitate on the surface. Excessive humidity will also cause the solubility of the highly polar compound to decrease, which will lead to frost spraying. The longer the storage time, the more obvious the spray on the rubber surface.

Five, rubber aging

In the process of long-term use of rubber products, due to the aging effect, its complete and balanced mesh structure will be destroyed, resulting in the chemical or physical combination between the compounding agent and the raw rubber molecules and the compounding agent is weakened, and the solubility of the compounding agent in the rubber system is reduced, resulting in frost spraying.

6. Excessive compounding agent

Improper dosage of the compound, especially excessive use, is one of the main reasons for rubber products to spray frost. The solubility of the powder in the summer compound is high, and the amount of a little more may not be visible at the time, but there will be frost spraying problems in autumn and winter.

Vii. Solution Measures

For the problem of rubber products spraying frost, the following measures can be taken to prevent and solve:

1. Optimization of formula design: reasonable control of the dosage of the compound to avoid excessive use.

2. Improve the process operation: to ensure uniform mixing, strict control of rubber mixing and vulcanization temperature, time and other process parameters.

3. Ensure the quality of raw materials: strict quality control of raw materials to avoid the use of raw materials with fluctuating quality.

4. Improve storage conditions: Optimize the storage environment to avoid adverse conditions such as high temperature, high humidity and high pressure.

5. Use anti-frost agent: Add an appropriate amount of anti-frost agent in the formulation design to improve the solubility of the compound in the rubber.

Through the above measures, can effectively reduce the occurrence of rubber products frosting phenomenon, improve product quality and performance.

FOREVER SEALS! Seals manufacturer, accept custom seals, from design to research and development, from production to testing, a full range of services. For more information, please contact FOREVER SEALS directly. FOREVER SEALS product experts are here to help you! Whatsapp: +86-18098184099；WeChat: +86-13049188460；  E-mail: sales@foreverseals.com.