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Best Polymers for Humidity Sensing

Best Polymers for Humidity Sensing

Best Polymers for Humidity Sensing

(OP)
I am working on a capacitive humidity sensor, using polymer as a dielectric between two electrodes, does anybody know which polymer would react best to water vapor or water moisture or Rh (Relative Humidity)?

RE: Best Polymers for Humidity Sensing

Cellophane is best. Nylon would also work.

RE: Best Polymers for Humidity Sensing

(OP)
Thank you! Would cellophane detect full range of relative humidity from 0% to 100%?

RE: Best Polymers for Humidity Sensing

I believe if cellophane is exposed to 100% humidity it will can swell so much that will not return to the same dimensions when dry. It depends on the temperature.

RE: Best Polymers for Humidity Sensing

Unless this is for a school project, it seems to me to be a hobby post.

Digikey lists 643 humidity sensors; can't see the world needing yet another one.
https://www.digikey.com/products/en/sensors-transd...

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RE: Best Polymers for Humidity Sensing

(OP)
Thanks for your reply. if Cellophane will at 100% Rh, swell and may not come back to its original position, or the reaction time will be very slow, it will not work in my application. , so what do you suggest? Do you have any other suggestions?

RE: Best Polymers for Humidity Sensing

You could just buy one; the cost to design, build, and calibrate one would be orders of magnitude more than

From Digikey https://www.digikey.com/product-detail/en/neptune-... $22 with ±1% accuracy, which is already less than the engineering time it took to find it.

Or this https://www.digikey.com/product-detail/en/sensirio... at $5.29, but ±1.5% accuracy

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
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RE: Best Polymers for Humidity Sensing

(OP)
Thanks for your reply, we are not hobbyists' and this is not a hobby project for us, we are serious in designing the sensor that will work better than your suggested Sensirion part from Digikey. We have designed the sensors and the probe to read the capacitive sensor with success and we are looking to have expert suggestions to improve our design. If you can suggest your ideas we highly appreciate. Please let us know if you can help.

RE: Best Polymers for Humidity Sensing

Work better in what way?

RE: Best Polymers for Humidity Sensing

Quote:

we are serious in designing the sensor that will work better than your suggested Sensirion part from Digikey. We have designed the sensors and the probe to read the capacitive sensor with success and we are looking to have expert suggestions to improve our design.

You claim to not be hobbyists, and are therefore likely to be students, who are forbidden from posting their coursework questions on this site. A company cannot possibly contemplate designing a "better" humidity sensor and have not even done basic research into dielectrics. Even a cursory literature or patent search would have resulted in a better starting question.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm

RE: Best Polymers for Humidity Sensing

How long we can store ABS in natural way?

RE: Best Polymers for Humidity Sensing

Decades.

I have a 32 year old motorcycle whose original-equipment ABS fairings are still in fine shape.

More details = better answers.

RE: Best Polymers for Humidity Sensing

What doesn't keep are the asinine coatings they put on to some tools that turn into goop after a year or so; I don't know if it base material was ABS or something else, but the goo is sticky and annoying

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm

RE: Best Polymers for Humidity Sensing

Karthik To answer your question on the storage time on ABS.

For quality retainment purposes it recommended storing ABS no longer than 3 to 5 years.


BudgetMoldking
Feel free to take a look at our website: Budget-Molding

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