Ammonium Polyphosphate, APP, 68333-79-9

AMMONIUM POLYPHOSPHATE (APP)

1. PRODUCT IDENTIFICATION AND CHEMICAL IDENTITY

Short Identity Section

Detailed Identification

Description:
Ammonium Polyphosphate (APP) is a halogen-free, phosphorus-based flame retardant. Under heat, it forms phosphoric acid, initiating the char formation mechanism and creating a protective barrier on the combustible surface. It is the key acid source in intumescent systems and is compatible with PP, PE, PA, PU, Epoxy, and Polyester systems. According to ECHA, it is registered with EC number 269-789-9 and CAS number 68333-79-9.

2. PHYSICAL AND CHEMICAL PROPERTIES

APP Phase I vs. Phase II Comparison

Critical Note: Nearly all products used in the flame retardant paint and plastics industry today are APP Phase II.

3. SOLUBILITY PROFILE

Note: APP Phase II has very low water solubility and is completely insoluble in organic solvents. Coated grades have even lower solubility.

4. CHEMICAL PROPERTIES AND REACTIONS

Incompatibilities

• Strong oxidizing agents

• Strong bases

• Active metals

Chemical Reactions

• Thermal Decomposition: APP decomposes to form phosphoric acid and ammonia under high temperatures (>300°C for Phase II).

• Intumescent Reaction: Phosphoric acid reacts with carbon source (e.g., pentaerythritol) to form polyphosphoric acid esters, leading to char formation.

5. SPECIFICATIONS

Critical Parameters for Fire Retardant Paint Manufacturers

Typical Specifications (Phase II)

Packaging Options

6. APPLICATIONS AND INDUSTRIAL USES

6.1 Role in Intumescent Paint

In intumescent paint systems, APP functions as the acid source:

During fire:

1. APP forms phosphoric acid.

2. Pentaerythritol carbonizes.

3. Melamine releases gas.

4. A thick swollen char layer is formed.

5. The steel surface is protected from heat.

6.2 Key Advantages

• Halogen-free

• Low smoke generation

• Environmentally friendly

• REACH compliant

• Key component of intumescent systems

• Compatible with PP, PE, PA, PU, Epoxy, and Polyester systems

6.3 Application Selection Guide

7. BIOLOGICAL AND STRUCTURAL PROPERTIES

Note: This product is an industrial flame retardant. It is not intended for biological, pharmaceutical, or food applications (except agricultural fertilizer use).

8. BIOCHEMICAL APPLICATIONS

Note: Not applicable for this industrial flame retardant.

9. SAFETY AND TOXICOLOGY

9.1 Acute Toxicity

9.2 Chronic Toxicity

9.3 GHS Classification

Note: Some SDSs classify APP as not a dangerous substance according to GHS. The harmonized classification from ECHA includes Acute Tox. 4 (H302) and Eye Irrit. 2 (H319).

9.4 Precautionary Statements

9.5 Safety Precautions and PPE

Hazards:

• Harmful if swallowed

• Causes serious eye irritation

• May cause mild skin irritation

PPE (recommended):

• Chemical-resistant gloves

• Safety goggles

• Suitable work clothing

• Dust mask (if dust is generated)

9.6 Environmental Fate

10. TRANSPORT INFORMATION

Note: APP is not classified as dangerous goods for transport.

11. REGULATORY INFORMATION

Note: APP is REACH registered and is SVHC-free according to Article 31 of the REACH Regulation (for grades with < 0.1% melamine).

12. STORAGE AND HANDLING

13. FIREFIGHTING MEASURES

Note: APP is non-flammable but may decompose under fire conditions, releasing toxic fumes.

14. ACCIDENTAL RELEASE MEASURES

15. FIRST AID MEASURES

16. RAW MATERIALS AND DOWNSTREAM PRODUCTS

16.1 Raw Materials (Upstream)

16.2 Downstream Products

17. SECTORAL SUITABILITY AND USAGE LEVELS

18. CARBON DIOXIDE ABSORPTION AND REAGENTS

Not applicable. APP is an industrial flame retardant and fertilizer and is not used for CO₂ absorption or as a chemical reagent.

19. DERIVATIVES AND RELATED COMPOUNDS

Note: APP is the primary acid source in intumescent systems, often used in combination with pentaerythritol (carbon source) and melamine (blowing agent).

20. SUMMARY AND CRITICAL WARNINGS

SUMMARY

Ammonium Polyphosphate (APP) is a halogen-free, phosphorus-based flame retardant. Under heat, it forms phosphoric acid, initiating the char formation mechanism and creating a protective barrier on the combustible surface. It is the key acid source in intumescent systems and is compatible with PP, PE, PA, PU, Epoxy, and Polyester systems.

It appears as a white powder (Phase II). Its P₂O₅ content is ≥69-72%, nitrogen content is ≥14%, pH is 5.5–7.5 (10% suspension), and degree of polymerization is >1000. It has very low water solubility (<0.1 g/100 mL) and is insoluble in organic solvents.

It is used in intumescent coatings for steel structures, flame retardant plastics (PP, PE, PA, PU), textile back-coatings, and as a high-phosphorus fertilizer.

Key Properties

Main Application Areas

Key Safety Points

• HARMFUL: Harmful if swallowed (H302).

• EYE IRRITATION: Causes serious eye irritation (H319).

• PPE REQUIRED: Use chemical-resistant gloves, safety goggles, and suitable work clothing. Use dust mask if dust is generated.

• STORAGE: Store in a cool, dry, well-ventilated area. Keep containers tightly closed.

• DISPOSAL: Dispose of according to local regulations.

Critical Warnings

• APP is not classified as dangerous goods for transport.

• Thermal decomposition may release nitrogen oxides, ammonia, and phosphorus oxides.

• This TDS contains complete toxicological, transport, firefighting, and first aid data, but always refer to the supplier's official SDS/MSDS.

• Do not use this TDS as a substitute for the official SDS/MSDS.

• Users are responsible for determining the suitability of the product for their specific applications and for complying with all applicable regulations and safety requirements.

APP Equivalents Table

One-Sentence Summary for Sales Team

• APP 201: Economical and general-purpose fire paint grade.

• APP 201F: Finer particle and smoother paint surface.

• APP 1201: Low-viscosity premium paint grade.

• APP 202: For exterior applications and systems requiring high moisture resistance.

• APP 203: Improved plastic and resin compatibility grade.

• APP 204: Silane-coated, ideal for PP/PE and cable compounds.

• APP 205: Special grade for epoxy-based flame retardant coatings.

Disclaimer:
This Technical Data Sheet (TDS) is for informational purposes only. The information provided is based on the original technical summary, verified CAS/EC numbers, and data completed from reliable sources (ECHA, manufacturer SDSs, technical data sheets). However, the user is solely responsible for determining the suitability of the product for their specific applications and for complying with all applicable regulations and safety requirements. For complete safety, handling, storage, and regulatory compliance information, always refer to the official Safety Data Sheet (SDS/MSDS) provided by the manufacturer/supplier. Users are responsible for testing the product in their own processes and applications. All local, national, and international regulations must be followed when working with Ammonium Polyphosphate (APP).