In the production of rubber and plastic products, magnesium oxide (MgO) is often used as an important additive, mainly serving as a vulcanization accelerator, stabilizer, and filler. In these applications, the specific indicators and quality requirements of magnesium oxide may vary depending on its purpose and required performance. Here are some common indicators of magnesium oxide:

1. Purity: Generally, the purity of magnesium oxide used in the rubber and plastic industry is required to be above 95%, and high-quality products can reach a purity of over 98%. High purity magnesium oxide can ensure the performance and stability of the product.

2. Particle size: The particle size of magnesium oxide has a significant impact on its dispersibility and reactivity in rubber and plastics. The commonly used magnesium oxide particle size is usually 200 mesh or finer, which ensures its uniform distribution in the matrix.

3. Active magnesium oxide content: This is an important indicator for measuring the activity of magnesium oxide, usually requiring an active magnesium oxide content of over 60% to ensure its effective participation in the sulfurization process.

4. Surface area: The specific surface area is usually between 10-30 m ²/g. A larger surface area helps to improve its reaction efficiency in rubber and plastic.

5. Whiteness: Whiteness is an important appearance indicator for magnesium oxide used in rubber and plastic, usually requiring a whiteness of over 90% to ensure the appearance quality of the final product.

6. Moisture content: Moisture content is usually required to be less than 0.5% to prevent adverse reactions during processing.

Magnesium oxide (MgO) used in the rubber and plastic industries typically has strict specification requirements to ensure its performance meets production needs. The following are more detailed and accurate indicators of magnesium oxide:

1. Chemical composition

·Magnesium oxide content (MgO): ≥ 95% -98%

High purity magnesium oxide used for rubber and plastics typically requires over 95%, and some high-end applications may require 98% or even higher.

·Calcium oxide (CaO) content: ≤ 1.0% -2.0%

The content of calcium oxide should be kept as low as possible to minimize its impact on product performance.

·Iron oxide (Fe2O3) content: ≤ 0.3% -0.5%

Iron oxide is an important impurity that affects whiteness and color, and its content is required to be as low as possible.

·Sulfate (SO4) content: ≤ 0.1%

High sulfate content may affect the aging resistance of rubber, so strict control is required.

2. Physical characteristics

·Granularity

Fineness (200 mesh pass rate): ≥ 98% -99%

D50 particle size: 2-6 μ m

Magnesium oxide used for rubber and plastics is usually a fine powder to ensure its uniform distribution and good reactivity in the matrix.

·Specific surface area: 10-30 m ²/g

A larger specific surface area helps to enhance its activity during the vulcanization process.

·Whiteness: ≥ 90%

High whiteness is an important factor in ensuring the appearance quality of products, usually requiring a whiteness of over 90%.

·Apparent density: 0.2-0.4 g/cm ³

Appropriate apparent density contributes to the uniform dispersion and processing performance of materials.

3. Moisture and other impurities

·Moisture content: ≤ 0.2% -0.3%

Low moisture content helps to avoid adverse reactions such as bubbles or pores during processing.

·Loss on Ignition (LOI): ≤ 3.0%

A low loss on ignition indicates high stability and purity of the material.

4. Activated magnesium oxide

·Active magnesium oxide content: ≥ 60%

The content of active magnesium oxide directly affects its efficiency as a promoter in the vulcanization process. A higher activity content helps to accelerate the vulcanization rate and increase the crosslinking density of the vulcanized rubber.

5. pH value

·PH value: 9-11

A suitable pH range helps maintain the stability of materials and avoid corrosion or degradation of rubber and plastic substrates.