I have to say that no matter what I'm wearing, I'm a very sweaty person by the time I make it into work. And that was on a 6 mile commute. I've just got a brand new 14 mile commute, and I expect I'll be at least as bad.
I have very short hair, which towel-dries nicely. I used to keep a face cloth at work and wipe down with that, then apply deodorent and hair wax. I also showered before leaving. Always a complete change of clothes at work, which I carry in in a rucksack. New workplace has a shower - hooray!!
Best of luck. I reckon that's quite a nice distance to commute.
Ellie