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With a growing global focus on sustainability, many states now require cleaner transportation fuels with lower carbon intensity to promote a more eco-friendly environment. This shift has led to the increased adoption of biofuels as an alternative to traditional petroleum-based gasoline. However, the introduction of new fuel blends presents challenges for vehicle fuel systems.

To address these challenges, Fluon+ Adhesive chemical bonding polymers provide an engineered solution.

Ethanol is among the most common biofuels, aiding in more efficient fuel combustion. According to the U.S. Energy Information Administration, ethanol accounted for the largest share of U.S. biofuel production and consumption in 2022. Despite its cleaner-burning properties compared to gasoline, certain ethanol blends can dry out the compounds used in fuel hoses, causing them to crack and soften. Extractables from the hoses also can block fuel injections, damage fuel system components, and reduce engine efficiency.

By using Fluon+ Adhesive chemical bonding polymers in hose construction, manufacturers can avoid these problems while also reducing permeation rates and vehicle weight, contributing to lower CO2 emissions.

What are Fluon+ Adhesive ETFEs?

Fluon+ Adhesive ETFEs are chemical bonding polymer resins made with Fluon+ Adhesive ethylene tetrafluoroethylene (ETFE). These specialized fluoropolymer compounds are used in applications requiring strong adhesion to polymers. They exhibit exceptional resistance to gas and fluid permeation, including automotive fuels.

These resins are formulated to chemically adhere to non-similar materials. They also provide dispersive properties not achievable with other fluoropolymers.

Adhesive ETFEs contain a unique function component that reacts with compatible groups to form a thermally stable chemical bond. As shown below, the bond maintains adhesion even in extended exposure to chemical environments.

For example, co-extruding ETFE with a polyamide produces a hose that cannot be delaminated even after thousands of hours of fluid exposure. Fluon+ Adhesive polymers also reduce cost, weight and processing time by eliminating the need for tie layers in multilayer construction.

Supplied in cylindrical pellet form, Fluon+ Adhesive polymers can be processed using various techniques including extrusion, injection molding, blow molding, transfer molding and compression molding.

Other automotive applications using Fluon+ Adhesive polymers include:

  • Liquid and vapor fuel lines
  • Fuel tanks
  • AC compressor hoses
  • Multilayer films and laminates
  • Tape, film and batteries

Benefits of Using Fluon+ Adhesive Polymers for Auto Hoses

In addition to giving hose components the chemical resistance and durability to stand up to aggressive biofuel blends, Fluon+ Adhesive chemical bonding polymers have low permeation rates to adhere to strict emissions standards. Even as the percentage of alcohol in fuel mixes increases, permeation rates decrease to as low as 0.40 g mm/m2 per day for alcohol fuel content up to 100% ethanol.

Permeation Rate of Fluon+ Adhesive as a Function of Increasing Ethanol Content in Fuel

By eliminating requirements for tie layers by producing multilayer hose constructions in one step without surface treatment, Fluon+ Adhesive chemical bonding polymers reduce weight to help car manufacturers adhere to stringent weight-saving restrictions in the U.S. and the world. Even modest decreases in vehicle weight can lessen C02 emissions as well as improve fuel economy.

In addition, Fluon+ Adhesive grades protect against static buildup to prevent static electricity from accumulating, which can create holes in the hose. These defects can cause fluid leaks and create a path for static electricity to attach to a conductive material, resulting in early part failure and operational problems.

All these properties of Fluon+ Adhesive polymers, including superior conductivity levels, provide high-performance characteristics to automotive hoses and other components.

A Selection of Fluon+ Adhesive Grades 

AGC Chemicals offers Fluon+ Adhesive chemical bonding polymers in different grades.   Each exhibits strong adhesion to polyamide polymers as well as high permeation resistance to many fluids and gases, especially automotive fuels.

Depending on application parameters like conductivity, temperature requirements or processing conditions, users can choose from Fluon+ AH-600, AH-700 or AH-800 series grades to create the inner layer of the fuel hose construction. AGC also offers a specialty LH-8000 grade with an ultra-low melting point.

  • AH-600 series polymers produce a lower-melting compound for a more flexible processing window, high-temperature performance and excellent stress crack resistance. They also offer strong compatibility with polyamide nylons for co-extrusion.
  • AH-700 series polymers balance performance with economics by providing a cost-effective solution without compromising performance. They offer process temperatures for high-melt nylons.
  • AH-800 series polymers provide high-temperature performance up to 200 °C and good stress crack resistance at elevated temperatures.
  • Fluon LH-8000 polymer is an ultra-low-melting adhesive resin with the widest processing temperature . While possessing the same properties as other grades of adhesive EFTEs, its ultra-low melting point makes it cost-effective for use in applications for hot water hoses and rubber hose mandrels, as well as anti-stick conveyor belts and interlayer insulation film for electronic substrates and tubes that convey harsh materials. With advanced adhesive properties, the ETFE LH-8000 polymer bonds to dissimilar materials such as polyamides, polyethylenes and metals.

AGC Fluon+ Adhesive chemical bonding polymers are the next generation of compounds that enable hose line constructions to perform with more volatile biofuels while meeting stricter emissions standards. To learn more about AGC adhesive grades, visit Fluoropolymer Compounds: Fluon+ Adhesive Grades


AGC Chemicals