Vertrel XF

Introduction to Vertrel XF

Vertrel XF is a proprietary hydrofluorocarbon fluid with zero ozone depletion potential and low global warming potential ideally suited for use in vapor degreasing equipment for cleaning, rinsing, and drying. It can replace current hydrochlorofluorocarbon (HCFC) and perfluorocarbon (PFC) fluids in most applications.

Vertrel XF is HFC 43-10mee or 2,3-dihydrodeca–fluoropentane; empirical formula C5H2F10. It is a clear, colorless liquid with the properties shown in Table 1.

Unique physical properties include a high density, low viscosity, and low surface tension. This combined with nonflammability, chemical and thermal stability, low toxicity, and ease of recovery by distillation make Vertrel XF ideal for a broad range of applications. Solvency is selective, but can be enhanced by use of appropriate azeotropes and blends with alcohols, hydrocarbons, esters, etc..

Typical Applications

• Cleaning and rinsing agent
• Drying fluid
• Particulate remover
• Fluorocarbon lubricant carrier
• Solvent and dispersion media
• Heat transfer media
• Dielectric fluid
• Replacement for many HCFC, PFC, and CFC-113 applications

Vertrel XF is ideally suited for cleaning fine particulate matter (submicron range) from metal and nonmetal parts. Removal of particle contamination requires a solvent that can minimize the thickness of the laminar boundary layer where particles are bonded to the substrate. If the boundary layer thickness is less than the particle diameter, momentum from the flowing solvent can efficiently dislodge the particles and carry them away. Vertrel XF, with its lower viscosity and higher density, results in a thinner boundary layer, which enhances cleaning. Common aqueous cleaning fluids, mixtures of water and detergent, have higher viscosities and lower densities compared to Vertrel XF, making these fluids less efficient.

The electronic attraction between particle and surface can be overcome further by increasing the polarity of the fluid through the addition of small amounts of alcohols. Chemours offers a series of proprietary azeotrope and blend compositions that exploit this property.

Another common cleaning technique is the addition of ultrasonics to the solvent. High frequency, ultrasonic waves produce tiny bubbles that form and collapse (cavitate) as the wave passes. Cavitation energy increases with decreasing viscosity, another advantage of Vertrel XF, improving its ability to mechanically dislodge particle contamination.

Vapor Degreasing Process

Use of modern vapor containment technology is recommended for both batch and in-line equipment. These systems have higher freeboard and a secondary set of low-temperature (–29°C [–20°F]) condenser coils to greatly reduce vapor losses from boiling solvent degreasing, defluxing, rinsing, and drying equipment.

Neat Vertrel XF can be used for rinsing, drying, and some cleaning applications, but use with other components, such as azeotropes or simple blends, can provide improved solvency and soil removal. Vertrel XF forms azeotropes or constant boiling mixtures with many similar boiling range components. Five nonflammable proprietary azeotrope compositions have been developed that are useful for general, as well as precision, cleaning and defluxing. See specific product bulletins for details.

Table 1. Density and Vapor Pressure Change with Temperature

Solvency

Unlike PFCs, Vertrel XF is completely miscible with most esters, ketones, ethers, ether-alcohols, and the lower alcohols, such as methanol, ethanol, and isopropanol. The lower hydrocarbons, such as hexane and heptane, are also soluble. Neat Vertrel XF has limited solvency for many higher molecular weight materials, such as hydrocarbon oils, silicone oils, waxes, and greases; here combinations with the many readily miscible esters, alcohols, and lower hydrocarbons can enhance solubility and cleaning efficiency. Like CFC-113 and PFCs, Vertrel XF has high solubility for Krytox and “Fomblin” fluorocarbon lubricants and can be used either as an application carrier fluid or to remove them.

Plastic and Elastomer Compatibility

A large variety of plastics and elastomers can be safely exposed to Vertrel XF. Tables 2 and 3 summarize test results on short-term exposures of unstressed plastics and elastomers, which simulate a typical cleaning cycle.

Long-term compatibility data simulating exposure of vapor degreaser construction materials is available from Chemours upon request.

Elastomer swelling and shrinking will, in most cases, revert to within a few percent of original size after air drying. Swell, shrinkage, and extractables are strongly affected by the compounding agents, plasticizers, and curing used in the manufacture of plastics and elastomers. Therefore, prior in-use testing is particularly important.

Table 2. Plastic Compatibility Immersion: 15 Minutes at Room Temperature

Table 3. Elastomer Compatibility Immersion: 15 Minutes at Room Temperature

*Material composition varies depending upon compounding agents, plasticizers, processing, etc. Specific materials should be tested for compatibility with solvent.

Metals and Other Compatibility

Vertrel XF is fully compatible with the metals listed below after exposure for two weeks at 100°C (212°F) in sealed tubes with and without water contact.

• Zinc*
• Stainless Steel
• Brass*
• Aluminum
• Copper*

*Slight discoloration with water present

Vertrel XF is not compatible with strong bases; therefore, contact with highly basic process materials is not recommended.

Exposure Limits

Data from acute toxicity studies has demonstrated that Vertrel XF has low toxicity. Vertrel XF is a slight skin and eye irritant and has low acute inhalation toxicity.

Safety/Flammability

Vertrel XF is nonflammable and does not become flammable during boiling or evaporation. It exhibits no closed or open cup flash point and is not classified as a flammable liquid by NFPA or DOT. It is thermally stable to 300°C (572°F) and does not oxidize or degrade during storage.

Recovery

Vertrel XF is a pure component material and is easily recoverable by off-line and in-line distillation equipment, such as a vapor degreaser or still. The presence of soil, however, may alter the characteristics of the material during the recovery operation. Recovery should be closely monitored to ensure operating levels are maintained. Users should test the spent Vertrel XF to ensure proper classification for waste disposal.

Storage/Handling

Vertrel XF is thermally stable and does not oxidize or degrade during storage. Store in a clean, dry area. Protect from freezing temperatures. Do not allow stored product to exceed 52°C (125°F) to prevent leakage or
potential rupture of container from pressure and expansion. Consideration should be given to retrofit of existing or purchase of new, vapor degreasing equipment to provide vapor containment technology that enables safe and economical use of Vertrel XF. Drum pumps are recommended to dispense Vertrel XF from its container. Refer to the Safety Data Sheet (SDS) for specific handling precautions and instructions.

Environmental Legislation

Vertrel XF has zero ozone depletion potential and a low global warming potential (Table 4). Vertrel XF and its azeotropes and blends are used as alternatives to CFC-113, methylchloroform, HCFCs, and PFCs in many critical cleaning, drying, carrier fluid, and other high-value specialty uses where reliability is paramount.

Vertrel XF is accepted by the U.S. Environmental Protection Agency (EPA) under the Significant New Alternatives Policy (SNAP) program as a substitute for ozone-depleting substances. HFC 43-10mee or
decafluoropentane is exempt from classification as a volatile organic compound (VOC) by the EPA. Vertrel XF is also VOC compliant under the California South Coast Air Quality Management District (SCAQMD) regulations, which require VOC content less than 50 g/L of solvent.

Vertrel XF is listed in the TSCA inventory. It is subject to the Significant New Use Rule (SNUR) and should be used only in the indicated applications. See SDS Regulatory Section.

Vertrel XF is not a hazardous air pollutant (HAP), and, therefore, not subject to NESHAP regulation. Spent Vertrel XF is not an RCRA characteristic or listed waste. However, addition of contaminants could change that status. Vertrel XF is not included in the SARA Title III Section 313 list of toxic chemicals and is not subject to SARA Title III (EPCRA) reporting requirements.

Table 4. Environmental Properties

*IPCC Second Assessment Report (1995)

Specifications

Composition and specifications are shown in Table 5. Vertrel™ XF is listed in the TSCA Inventory.

Table 5. Vertrel XF Specifications