From the LA Times:
This week, our friend to the north introduced the first in its new line of all-plastic notes — a cool $100 bill made out of a single sheet of plastic polymer and tricked out with all kinds of high-tech security features.
In a statement, the Bank of Canada said that the new notes will last twice as long as paper money and will also be recycled, which makes them generally greener (even though the $100 bill is kind of yellowish in color).
But the real impetus to move to plastic money was making the money more difficult to counterfeit.