Polymers that aren't brittle at the cryogenic temperatures found on Titan?
According to NASA1 the main factor inhibiting the widespread use of polymer materials in space environments is oxygen erosion, the materials tested so far to be proven effective in space are  Teflon, Mylar, Kapton and Tedlar.
Further experimentation is being conducted on board ISS according to their website2.
I do not believe there are polymers currently capable of handing the cold, pressure, and oxygen erosion of Titan, as such, the probe3 Huygens sent to Titan was constructed of aluminum coated Kapton, which seems to be the industry standard for space environments.
References:

https://www.nasa.gov/centers/glenn/shuttlestation/station/misse.html
http://www.spacestationresearch.com/tag/polymer-erosion-and-contamination-experiment-polymers/
https://en.wikipedia.org/wiki/Huygens_(spacecraft)