CELANESE HOSTAFORM® C 13031 XF 50/5339 POM

1. Introduction

2. Material Properties

The comprehensive characterization of Hostaform® C 13031 XF 50/5339 reveals a material engineered for high performance in demanding environments.

2.1 Physical Properties

The moderate MVR value suggests a balanced flow for injection molding, while low water and humidity absorption ensure excellent dimensional stability and simplify preprocessing.

2.2 Mechanical Properties

High impact strength, especially at low temperatures, is crucial for automotive applications. Detailed stress-strain and secant modulus-strain diagrams are available, showing data across a wide temperature range from -40°C to 120°C, ensuring comprehensive understanding of the material's response to varying thermal conditions and sustained loads.

2.3 Thermal Properties

These thermal properties confirm suitability for high-temperature environments, such as engine compartments and modern direct injection fuel systems, where temperatures can exceed 100°C. Flammability ratings ensure compliance with crucial safety regulations.

2.4 Electrical Properties

While primarily designed for fuel system applications, Hostaform® C 13031 XF also possesses strong electrical insulating capabilities, broadening its utility for components requiring both mechanical robustness and electrical insulation.

2.5 Chemical Resistance and Fuel Compatibility

Hostaform® C 13031 XF is an acetal copolymer specifically modified to resist deterioration from aggressive fuel blends. It demonstrates good chemical resistance to various solvents, fuels, and strong alkalis, coupled with good hydrolysis resistance.

This material was specifically developed to meet the demanding requirements of modern diesel direct injection systems, which can lead to significant increases in fuel system temperature (often exceeding 100°C) and aggressive decomposition products.

Rigorous testing includes immersion in Haltermann test diesel at 100°C. Further extensive testing involved immersing Hostaform® C 13031 XF in US#2 ultra-low sulfur diesel (nominal 15 ppm sulfur) and derivatives at 90°C for 6000 hours, with weekly fuel refreshes. Results for both US#2 diesel and biodiesel blends (B20 using soybean methyl esters) showed moderate mass change levels, confirming robust performance even with increased biofuel content.

This material is specifically engineered and validated for the complex chemical and thermal environment of modern diesel and biodiesel systems, providing high confidence for automotive designers.

3. Typical Applications

Hostaform® C 13031 XF 50/5339 is primarily and specifically targeted for applications within the transportation industry's fuel systems. Its properties make it ideal for molded parts that demand higher requirements for strength, rigidity, and hardness, particularly in scenarios involving direct contact with fuels.

The material was developed to meet the stringent demands of modern diesel direct injection systems, which operate at elevated temperatures and expose materials to aggressive fuel decomposition products.

• General Fuel System Components: The distinctive yellow (50/5339) variant serves as a visual indicator of its specialized purpose.
• Laser-Welded Components: The black (10/9022) variant is specifically available for applications that incorporate laser welding, providing manufacturing flexibility.

This material is a specialized solution for high-performance, high-reliability applications where material failure could have severe consequences, making it a preferred choice over less specialized materials.

4. Processing Guidelines: Injection Molding

Hostaform® C 13031 XF 50/5339 is primarily processed using injection molding. Adhering to specific guidelines is crucial for achieving optimal part quality and performance.

4.1 Preprocessing Recommendations (Drying)

General drying is typically not necessary due to its inherently low moisture absorption, streamlining the manufacturing workflow.

However, if exposed to adverse storage conditions, drying is recommended to prevent issues like splay and odor. Use a recirculating air dryer at 100-120 °C for 3-6 hours, with a maximum layer thickness of 40 mm. Maximum residual moisture content should be 0.15%, with a maximum allowable water content of 0.2%.

4.2 Temperature Parameters

These detailed temperature profiles ensure optimal melt viscosity for filling and packing, minimizing internal stresses and achieving desired part properties.

4.3 Pressure and Speed Parameters

The recommended holding pressure (600-1200 bar) allows flexibility in mold packing. Back pressure should be kept at a maximum of 40 bar. Slow to medium injection speed is advised to prevent excessive shear heating and ensure uniform mold filling. Screw speeds vary with diameter to maintain consistent shear and melt quality.

4.4 Equipment Considerations

Standard injection molding machines equipped with three-phase (15 to 25 D) plasticating screws are suitable, making the material accessible to a wider range of manufacturers without specialized equipment.

4.5 Postprocessing

Post-molding conditioning, such as moisturizing, is not necessary due to the material's low moisture absorption, further streamlining the manufacturing process and reducing production costs.

5. Regulatory Compliance and OEM Approvals

The extensive list of regulatory compliances and OEM approvals for Hostaform® C 13031 XF 50/5339 underscores its established reliability and suitability for critical applications, particularly within the automotive sector.

This extensive list of OEM approvals signifies that Hostaform® C 13031 XF is a highly trusted and de-risked material for automotive applications, particularly in critical fuel systems, significantly reducing qualification time and costs.

6. Important Considerations for Use

While Hostaform® C 13031 XF 50/5339 offers exceptional properties, several important considerations must be taken into account for its successful and reliable application.

• Influence of Factors on Part Properties: The properties of molded parts are influenced by material selection, additives, part design, processing conditions, and environmental exposure. Optimal performance requires a holistic approach considering all these variables.
• User Responsibility for Suitability: Users are solely responsible for determining the suitability of a particular material and part design for any contemplated use. Comprehensive validation beyond standard data sheets is essential.
• Practical Trials for Fuel Aging: Despite extensive laboratory testing, practical trials are essential before using this grade in a final product. The aging behavior of diesel fuel in a running engine is complex and not fully defined by laboratory conditions, necessitating real-world validation.
• Product Availability Status: As of June 12, 2025, the availability of Hostaform® C 13031 XF 50/5339 could not be confirmed. Direct contact with Celanese is crucial for the most current information regarding product availability and supply chain viability to avoid significant commercial risks.