Polymer industry ozone depletion

In industry, lower esters, such as ethyl acetate (b.p. 77°C) and butyl acetate (b.p. 127°C), are used as solvents. For example, butyl butanoate has replaced the ozone-depleting tri-chloroethane as a cleaning solvent in the manufacture of electronic components such as computer chips. Higher nonvolatile esters are used as softeners (called plasticizers see Section 12-15) for brittle polymers—in flexible tubing (e.g., Tygon tubing), rubber pipes, and upholstery. 

Polymeric foams are widely used in a variety of industries. Polymer nanocomposite foam based on combination of functional nanoparticles and foaming technology leads a new class of material. Polystyrene (PS) foam is our main focus, which possesses about 26% of the polymer foam market of U.S. (2001 data), second only to polyurethane (PU) (53%). Polymer foaming with CO2 has been an active area recently because of restrictions on the use of ozone-depleting substances. CO2... 

HCFC/HFCs) currently widely used in the foam industry. However, HCFCs still destroys the ozone layer (much less than CFCs). Although HFCs are considered to have an ozone depletion potential of zero, they are still greenhouse gas. The second type is hydrocarbons. Due to their high flammability and volatile nature, hydrocarbons are considered as fire hazards. The third type is inert gases, e.g. H2O, CO2, and N2. CO2 has better solubifity in polymers than the other two and supercritical state of CO2 is relatively easier to reach. In summary, in all these potential alternatives, CO2 is the most preferable because it is nonflammable, inexpensive, essentially nontoxic and environmentally friendly. ... 

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