Sylgard 184: PDMS

Sylgard 184, a Dow Corning Corporation product, is a silicone elastomer kit. The kit contains two chemicals: Base (part A) and Curing Agent (part B), that are mixed in 10:1 mass ratio. Both the chemicals are transparent, but quite viscous in nature. Please don't use pipettes to draw the chemicals as they are pretty thick. Also, wear gloves when handling these chemicals.

The Base (part A) contains the followings:

1. Dimethyl siloxane, dimethylivinyl terminated - 68083-19-2
2. Dimethylvinylated and trimethylated silica - 68988-89-6
3. Tetra (trimethoxysiloxy) silane - 3555-47-3
4. Ethyl benzene - 100-41-4

VOC content: 8 grams/liter

The Curing Agent (part A) contains the followings:

1. Dimethyl, methylhydrogen siloxane - 68037-59-2
2. Dimethyl siloxane, dimethylvinyl terminated - 68083-19-2
3. Dimethylvinylated and trimethylated silica - 68988-89-6
4. Tetramethyl tetravinyl cyclotetra siloxane - 2554-06-5
5. Ethyl benzene - 100-41-4

Maximum VOC content including water: 85 grams/liter

Sylgard 184 has been used in making solar panels. Here is a Youtube video.

Spin Casting of Sylgard 184

Sylgard 184 can also be spin cast to produce PDMS. Although it has not been studied extensively, a couple of papers describe spin casting of Sylgard 184. Normally, the base (part A) and the curing agent (part B) are mixed in 10:1 ratio as recommended by the manufacturer, and then dissolved in a n-alkane like n-hexane or n-heptane before spin casting.

• Patrito et al (Langmuir, 2006, 22, 3453-3455) diluted the Sylgard mixture to 5 weight percentage in n-heptane, and then spun cast at 3000 rpm for 30 seconds to produce 220 +/- 30 nm thick coating.
• Lange et al (Anal Chem, 2009, 81, 10089-10096) dissolved the 10:1 Sylgard mixture to hexanes to 26 weight percentage, and then spun cast at 2000 rpm for 120 seconds to obtain ~1.4 micrometers thick coating.