To make informed design decisions when working with polymers, it's imprortant to have a solid understanding of material properties of plastic. Below you'll find an index of common plastic material properties and standard test methods, including their descriptions with several helpful diagrams. It's also important to understand plastic material properties and the terms used by suppliers, and how their materials perform in various conditions. This understanding will also help you compare different grades.
Detailed material properties of plastics information for specific grades of plastics are available in the Prospector Plastics Database.
Also, be sure to reference an excellent article written by Micheal Sepe titled Getting the Most Out of Your Plastics Data.