Parylene series of materials Parylene C

1.Basic information of Parylene C

Product name: Dichlorop-xylene dimer

Alias: Parylene; Parylene C, Dichlorodi-p-xylylene, Dichloro-[2,2]-paracyclophane

Purity: ≥99.5%

CAS Number: 28804-46-8

Molecular formula: C₁₆H₁₄Cl₂

Molecular weight: 277.193

Appearance: white crystalline powder, white particles

Melting point: 165-167°C (MP)

Storage conditions: Store at room temperature

Usage description: Parylene C is a protective polymer material, which can be vapor deposited under vacuum. The penetrating power of the molecules enables it to form a pinhole-free high-quality protective layer inside, at the bottom, and around the component. It can be used in microelectronics, semiconductors, printed circuit board biosensors, cultural relics protection and other fields.

2.Introduction of Parylene C

     Compared with parylene N, only one hydrogen atom on the benzene ring is replaced by a chlorine atom. Parylene C combines effective electrical and physical properties, and has lower permeability to moisture, liquids and corrosive gases. It can provide a pinhole-free coating barrier and can be applied to the coating of key medical electronic components.The advantage of Parylene C is that it is deposited on the substrate faster than parylene N. The disadvantage is that the film has poor thermal aging resistance, UV aging resistance, and radiation aging resistance.

3.Coating examples¹

   316L grade stainless steel is selected as the substrate, and the coating steps are as follows:

 (1) Adopt dipping method (solution: 0.5 vol% methacryloxypropyltrimethoxysilane dissolved in 50% water/50% isopropanol, immersion time: 30 minutes, drying treatment: high pressure argon at 65°C Dry under air for 30 minutes), cover a layer of silane coupling agent A174 on the surface of stainless steel metal;

(2) Coating by CVD method through Para Tech Coating Scandinavia AB equipment. Parylene N dimer, as the precursor, decomposes into reactive monomers at 650℃, and then spontaneously deposits and polymerizes at room temperature.

4.Parylene C film properties

Table 1. Thermal properties of parylen C

Table 2. Mechanical properties and barrier properties of parylene C

 Table 3. Electrical properties of parylene C

References:

1.Parylene coatings on stainless steel 316L surface for medical applications—Mechanical and protective properties,Materials Science and Engineering C,2011,doi:10.1016/j.msec.2011.09.007