Dear all:
I've been bugged by a question: For preparation of water-borne polyurethane, why is it OK to disperse NCO-terminated polyurethane prepolymer into water? Doesn't NCO react readily with water?
For some cases NCO is blocked first, but in most cases unprotected NCO is exposed to water...
Hi, all:
Can anyone help me with "laser hardening"? It appears to be a common process to increase the surface hardness of the metal (correct me if I'm wrong), and I also learned it can increase the damage threshold of optical windows. I've googled it but couldn't find why it works. Appreciate...
Do flexibility and flatness defy each other inherently? Or is it more about a matter of how the film is processed? Commercially available Kapton films and PET transparencies are flexible and "look" flat, and I'm wondering if a better processing can bring roughness down to 1 nm rms?
Thanks.
simonwei
Hi,
I'm looking for commercially available films with following properties:
1. Heat-resistant up to 160 oC
2. Surface roughness rms below 1 nm
3. Stand-alone
4. 0.1 ~0.5 mm thick
I've tried some Kapton films but the flatness is not desirable. Can anyone suggest other. Thanks.
simonwei
