For those that are interested in the different materials & why vinyl causes static but leather doesn't. Leather would be similar to human hands for the purpose of comparison.
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The following table shows you the triboelectric series for many materials you find around the house. Positive items in the series are at the top, and negative items are at the bottom:
Human hands (usually too moist, though)
Very positive
Rabbit Fur
Glass
Human hair
Nylon
Wool
Fur
Lead
Silk
Aluminum
Paper
Cotton
Steel
Neutral
Wood
Amber
Hard rubber
Nickel, Copper
Brass, Silver
Gold, Platinum
Polyester
Styrene (Styrofoam)
Saran Wrap
Polyurethane
Polyethylene (like Scotch Tape)
Polypropylene
Vinyl (PVC)
Silicon
Teflon
Very negative
(The above list is adapted from Nature's Electricity, by Charles K. Adams.)
The relative position of two substances in the triboelectric series tells you how they will act when brought into contact. Glass rubbed by silk causes a charge separation because they are several positions apart in the table. The same applies for amber and wool.
The farther the separation in the table, the greater the effect.
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So if you wear nylon clothing and rub against vinyl seats, there is a great difference in charge. The nylon will strip free electrons from the vinyl. Now your body has free electrons. Touch the metal car, which is neutral, and the electrons ZAAAAAP from you to the car.
The full article discussing the above material list is
HERE