TPU and infrared rays

What wavelength of IR? Not that that really matters. IR is not able to break bonds or molecules. It only has enough energy to excite vibrations, which are reversibly converted to heat. For degradation or electron excitation, you need UV. These statements are not unique to TPU, either. All organic materials will act the same way.

I can imagine some unique and/or specialized circumstances where IR would appear to alter a TPU, such as the heating is sufficient to induce thermal degradation or crosslinking, but that really is not an IR effect.

John Aspen Research, -

Opinions expressed herein are my own and may not represent those of my employer.

Good to know that there are no other side effects. I'm using IR in order to temper inline wheel :)

Thanks for your response

--Armin

I'm not sure that you are accomplishing much. IIRC, inline wheels are crosslinked so that tempering will not allow you to release stresses. They are also not crystalline, so you are not increasing crystallinity either.

John Aspen Research, -

Opinions expressed herein are my own and may not represent those of my employer.

Yes, it should be so .. but the reality is different. Inline wheels are hitting sometimes very *fresh* the market with a high crystallinity of its material.

I do tempering in order to increase the crosslinks ... the result is remarkable.

--Armin

Tell me more. I'm curious about what performance changes you are seeing: increase/decrease in durometer/traction/rolling resistance, and why can't you just buy wheels that have these characteristics initially.

John Aspen Research, -

Opinions expressed herein are my own and may not represent those of my employer.

After tempering the inline wheels with IR (procedure posted in ec.sport.skating.inline ) I see an increased durometer of the working surface, less rolling resistance and good rebound. The abrasion is also decreased.

Good question :) IMHO, it isn't always in the interest of the manufacturers to sell wheels with decreased abrasion. The business of selling inline wheels is a seasonal one, so the wheel material got no time to ripe at room temperature.

--Armin