MDH PM5SN vs. M5SM: Top Flame Retardant Showdown in EVA Formulas

Magnesium Hydroxide: A Superior Flame Retardant for Rubber and Plastics

Magnesium hydroxide (MDH) is a highly effective flame retardant widely used in rubber and plastic industries. During thermal decomposition, it releases water and absorbs significant heat, lowering the surface temperature of synthetic materials in flames. This process suppresses polymer breakdown, cools combustible gases, and generates magnesium oxide—a robust refractory material that enhances fire resistance. Additionally, the water vapor produced helps suppress smoke, making MDH a triple-threat solution: flame retardancy, smoke suppression, and filling. This article explores its performance through rigorous testing, showcasing its value in real-world applications.

Test Methodology: Evaluating Magnesium Hydroxide Performance

Materials Used

• Ethylene-Vinyl Acetate Copolymer (EVA): Grade 7470K, 26% vinyl acetate content, sourced from Formosa Plastics Group.
• Magnesium Hydroxide Variants:

  • KMT PM5SN (1–2 μm particle size, ≥99% purity, coated), from KMT Industrial HK Limited.

  • NikoMag M5SM (2 μm particle size, ≥99.8% purity, coated), from NikoMag.

Equipment

• Sample Preparation: Banbury mixer, Plate Curing Press, mold, SY-6210-A Electronic Pulling Force Machine.

• Testing: Universal testing machine, melt flow tester, oxygen index meter.

Conditions

• Lab temperature: 23°C

• Humidity: 40%

Sample Preparation Process

1. Preheat Banbury mixer to 100–120°C.

2. Mix materials for 30 minutes at 200 ± 10°C.

3. Place dough into a preheated mold (1 ± 0.1 mm thick).

4. Press using Plate Curing Press (prepress: 10 MPa, pressure: 10–15 MPa, 220°C, 2-minute preheat).

5. Cool samples to 40–50°C.

Test Results: KMT PM5SN vs. NikoMag M5SM

Material Specifications

1. Elongation at Break

Insight: PM5SN outperforms M5SM in flexibility.

2. Tensile Strength

Insight: PM5SN demonstrates superior strength.

3. Melt Flow Index (MFI)

Insight: PM5SN’s lower MFI indicates better processing stability.

4. Limiting Oxygen Index (LOI)

Insight: PM5SN offers enhanced flame retardancy.

Conclusion: Why KMT PM5SN Stands Out

Testing reveals that KMT PM5SN outperforms NikoMag M5SM in an EVA-based formula, excelling in flame retardancy (higher LOI), mechanical strength (tensile and elongation), and processing performance (lower MFI). These results make it an ideal choice for manufacturers seeking reliable, high-performance flame retardant solutions.

About KMT Industrial HK Limited

Based in Gansu, China, KMT Industrial HK Limited specializes in researching and manufacturing magnesium hydroxide, natural brucite powder, and aluminum hydroxide.

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