Competitive Melamine Polyphosphate (MPP) prices that fit your budget—flexible terms and customized quotes for every order.
For samples, pricing, or more information, please call us at
+8615380400285
or mail to
sales2@liwei-chem.com.
We will respond to you as soon as possible.
Tel: +8615380400285
Email: sales2@liwei-chem.com
As a leading Melamine Polyphosphate (MPP) supplier, we deliver high-quality products across diverse grades to meet evolving needs, empowering global customers with safe, efficient, and compliant chemical solutions.
How to control the degree of polymerization during the preparation of Melamine Polyphosphate (MPP)?
This material is made by using melamine and polyphosphoric acid as raw materials, and adding them into a stainless steel reactor at a molar ratio of 1:1.2. A small amount of deionized water is added to adjust the consistency, and the solid content is controlled at 70%. The temperature is raised to 200℃, the stirring rate is 30 rpm, and the reaction is carried out for 4 hours. During this period, the degree of polymerization is monitored by sampling and measuring the viscosity, such as controlling the twist of spinning. The reaction is terminated when the viscosity reaches 500mPa・s. The degree of polymerization needs to be precisely controlled at 10-20. If it is too high, it will be difficult to melt, and if it is too low, the flame retardant efficiency will be insufficient. After the reaction, it is granulated by a twin-screw extruder (temperature 180℃), and then crushed into 80 mesh powder after cooling, namely Melamine Polyphosphate (MPP). Its nitrogen content is 35%±0.5%, phosphorus content is 20%±0.3%, thermal decomposition temperature is 320℃, and moisture content is <0.2%. This process is like boiling sugar to collect juice. Only when the temperature is right can a uniformly polymerized product be obtained, which is the core of the intumescent flame retardant system.
What is the effect of Melamine Polyphosphate (MPP) in intumescent fire retardant coatings?
This product is a key component of intumescent fire retardant coatings. It is compounded with pentaerythritol and melamine in a ratio of 3:1:1, with a total addition of 60%, and mixed with acrylic emulsion to form a coating. When applied to a steel plate (dry film thickness 1mm), it will foam and expand within 30 seconds when exposed to fire. The thickness of the carbon layer is 20 times that of the original film, forming a honeycomb insulation layer, and the thermal conductivity coefficient is reduced to 0.02W/(m・K). According to the flame retardant test, it can withstand 1000℃ flame burning for 90 minutes, and the back temperature of the steel plate does not exceed 140℃, which meets the first-level standard of GB 14907-2018. It has good compatibility with coating resins, no sedimentation after 6 months of storage, coating adhesion reaches level 1, and no wrinkles in water resistance test (immersion for 7 days). Therefore, it is widely used in fire-resistant coatings such as steel structures and tunnels. It is smokeless and non-toxic when burning, the carbon layer is tough and not easy to fall off, and the fire retardant effect far exceeds that of traditional coatings.
What is the synergistic effect of Melamine Polyphosphate (MPP) with other phosphorus and nitrogen flame retardants?
This material is used in combination with aluminum hydroxide (ratio 2:1) and added to polypropylene. The flame retardant level is increased from UL94 V-2 to V-0, and the oxygen index is increased from 25% to 33%, because aluminum hydroxide absorbs heat and cools down, which complements the carbonization and oxygen barrier of MPP. When compounded with expanded graphite (3:2), it is used in epoxy resin, the carbon layer expansion height increases by 50%, and the structure is denser, and the flame scour resistance is improved by 40%. In polyamide, it can reach V-0 level with 15% of MCA in a 1:1 ratio, which is 5% less than that of MPP alone, and the mechanical property retention rate is increased by 10%. Its synergistic effect is like a battle of military tactics, each showing its strengths, so it can reduce the amount of addition and reduce the impact on the performance of the substrate, providing a flexible solution for multi-system flame retardancy.
How is the solvent resistance of Melamine Polyphosphate (MPP) manifested?
Its powder was immersed in ethanol, acetone, and ethyl acetate for 72 hours, and the weight loss rate was <0.5%, indicating excellent resistance to organic solvents. In aqueous systems, it is stable at pH 6-8 and has no precipitation after storage for 30 days. In strongly acidic (pH <3) or strongly alkaline (pH >10) solutions, it will slowly decompose within 24 hours, so the pH of the system needs to be controlled. For solvent-based coatings, after being mixed with xylene, butanol, etc., the viscosity change rate is <8%, the spraying performance is stable, and there are no pinholes after film formation. This property makes it suitable for solvent-based and water-based systems, broadens the scope of application, and solves the problem of poor adaptability of some flame retardants to solvents.
What are the key points for processing and storage of Melamine Polyphosphate (MPP)?
This product is packaged in iron barrels lined with plastic bags, 50kg per barrel, and the barrel cover is equipped with a rubber seal to prevent air leakage. Store in a ventilated warehouse, the temperature is less than 35℃, away from open flames, and stored separately from oxidants. The stacking height should not exceed 6 barrels, and the bottom should be padded with wooden pallets to prevent moisture. During processing, it is necessary to avoid contact with strong acids and alkalis, and the mixing equipment should be made of stainless steel to prevent corrosion. During extrusion processing, the temperature must be lower than 300℃ to prevent decomposition, and the screw speed should be 200 rpm to ensure uniform dispersion. If it absorbs moisture and agglomerates accidentally, it can be reused after drying at 105℃ for 2 hours and passing through a 60-mesh sieve. The flame retardant performance remains unchanged and does not affect production continuity.
What is unique about the flame retardant mechanism of Expanded Graphite?