Parylene

Name:
Parylene
Detailed information:
Generic name for thermoplastic film polymers based on p-xylylene and made by vapor-phase polymerization.

Derivation:

p-xylene, CH3C6H4CH3, is heated with steam at 950C to produce the cyclic dimer di-p-xylylene, a solid that can be separated in pure form. The dimer is then pyrolyzed at 550C to produce monomer vapor of p-xylylene, CH2:C6H4:CH2, which is then cooled below 50C and condenses on the desired object as a polymer having the repeating structure —(CH2C6H4CH2—)n, with n about 5000 and molecular weights of about 500,000. The polymer is used as a protective coating. Films as thin as 500 Å to 5 mils are obtained.

Use:

Thin coatings of high purity and uniformity on almost any substrate that will resist a high vacuum, as paper, fabric, polyethylene and polystyrene film, ceramics, metals, many solid chemicals; electronic miniaturization systems; capacitors; thin film circuits.