provided in 4.5 lb. containers. To simplify the production, portions of the resin and

curing agent were transferred into opaque HDPE bottles.


Table 3.1 Typical properties of Silastic T-2 Silicone Moldmaking Rubber (from Dow
Corning product information sheet)
Test Unit Result
As Supplied
Base Color Translucent
Viscosity Centipoise or mPa-s 50,000
Curing Agent Color Transparent
Viscosity Centipoise or mPa-s 550

As Mixed 100 Parts Base to 10 Parts Curing Agent by Weight
Viscosity Centipoise or mPa-s 55,000
Specific Gravity 1.12

As Cured 24 Hours at 25C
Durometer Hardness, Shore A Points 42
Tensile Strength Psi 800
Elongation Percent 300
Tear Strength, Die B ppi 120
Linear Shrink Percent < 0.1


 Two vinyl terminated linear PDMS oils and one bulky vinyl terminated oil were

added to the resin to change the mechanical properties of the elastomer. A variety of

non-functional PDMS oils of varying molecular weights were also examined for surface

energy analysis. The molecular formula, viscosity, and molecular weight of each

additive are given in Table 3.2. All were obtained from Gelest, Inc. and stored at room

temperature. Five solvents were used for contact angle analysis: 1-Propanol (Aldrich,

99+% spectrophotometric grade), acetonitrile (Aldrich, 99.93+% HPLC grade), N,N-

dimethylformamide (Aldrich, 99.9+% HPLC grade), diiodomethane (Aldrich, 99%), and