Engineering360: "Transparent polymer is as strong as aluminum"

This is great for weight reduction in automobiles. Glass is a fairly large contributor to vehicle weight, and reducing weight is the best way to improve both performance and economy.

A bonus, is this weight reduction is located well above the center of gravity.

Hope this makes it to market soon. It would be a great replacement for the Lexan windows in my race car.

Might this be good for spacecraft windows (redundants)? Or is there a problem with thermal expansion and contraction?

This is great news for the reasons stated above. Also, many modern cars use the windscreen to stiffen the chassis.

What is the scratch resistance and transmission of UV and IR light?

I suspect that existing scratch-resistant and UV-blocking coatings could be applied to this material.