Product name: Octafluorocyclobutane

CAS: 115-25-3

Molecular formula: C4F8

Molecular weight: 200.03

EINECS: 204-075-2

Octafluorocyclobutane Chemical Properties

Boiling and Melting Points: It has a low boiling point (approximately -6.04°C) and a melting point of approximately -41.4°C. It easily exists in a gaseous state at room temperature. After liquefaction, it requires pressurization or low-temperature conditions for storage and transportation.

Density: Its gaseous density is much greater than that of air (relative density to air, approximately 6.0, air = 1); its liquid density is relatively high, approximately 1.51 g/cm³ at 25°C.

Solubility: It is extremely insoluble in water (approximately 0.001 g/L at 25°C) and in most organic solvents (such as ethanol and ether), but soluble in some perfluorinated solvents (such as perfluorohexane).

Stability: Its vapor pressure increases significantly with increasing temperature (approximately 1.7 MPa at 20°C). It is non-corrosive, non-flammable, and does not support combustion.

Octafluorocyclobutane Use

1. Electronics Industry: Plasma Etching and Cleaning

This is one of its primary applications. In semiconductor and chip manufacturing, octafluorocyclobutane can be used as a plasma etching gas. Using a high-frequency electric field to generate a plasma, it selectively removes specific areas of materials such as silicon and silicon dioxide, enabling precise fabrication of chip circuits. Furthermore, its inertness prevents it from reacting with chip components, making it suitable for plasma cleaning of residual contaminants after photolithography, ensuring chip precision.

2. Electrical Equipment: Insulation and Arc-Quenching Medium

Due to its excellent insulating properties and non-flammability, it can replace some traditional insulating gases (such as sulfur hexafluoride (SF₆), which offers stronger insulation but a high greenhouse effect). It is used in electrical equipment such as high-voltage switches, transformers, and capacitors to provide insulation, prevent arcing, and extinguish arcs. It is particularly suitable for applications where safety and environmental friendliness are crucial. 

3. Refrigeration and Heat Pumps: Environmentally Friendly Refrigerant (Alternative Uses)

Its thermodynamic properties are well-suited to medium- and low-temperature refrigeration needs, and its ozone depletion potential (ODP) is zero. It has been used as an alternative refrigerant (replacing ozone-depleting refrigerants such as chlorofluorocarbons) in certain low-temperature refrigeration systems and heat pump equipment. However, due to its potential greenhouse effect, its use must be regulated in accordance with environmental standards.

4. Other Industrial Applications

It can be used as a gas insulation material, creating an inert protective atmosphere in sealed electrical cabinets and precision instruments to prevent oxidation and moisture.

In polymer synthesis, it can be used as a polymerization reaction medium or foaming agent (decomposition conditions must be controlled) in the preparation of fluoropolymers.

It can also be used as an inert shielding gas in specialty welding to prevent the weld from reacting with air and degrading weld quality.