Polyolefin

[10-K]

Would clothing made of this polymer good for hiking?

Here's a description from Campmor:

Benefits of Polyolefin:

Wicking- Polyolefin material wicks moisture away from the skin more effectively than any other fiber, keeping the wearer warm and dry.
Superior Insulation- Polyolefin has the highest insulating capacity of any fiber, natural or man-made.
Warmth without bulk while being extremely durable.
Will not fade when exposed to sunlight
Washable and care-free.
Does not retain odors.
Sounds great but I've never heard of it before.

[Persistent]

Polyolefin is a general term referring to polymers of olefins (such as ethylene, propylene, butadiene, etc.). In this case, I am confident that they are referring to polypropylene which does exhibit the properties stated and is commonly used in camping/hiking clothing.