New sensor material for measuring deformation, humidity, temperature, pressure ... and then what?

Hi Habra!
It so happened that I was born in the Soviet Union. It was a small science city near Moscow, in a family of researchers. He grew up in the best traditions of the end of the Soviet era, studied in an ordinary school. Physics and mathematics were easy for me, but the humanities are not very good. In high school, he began preparing for college, and on weekends he dug potatoes and collected Colorado beetles, but he dreamed of being a businessman and wearing a red jacket. As planned, I enrolled in a decent technical university, graduated from it, and received the degree of engineer-physicist, like my father. But the desire to earn more than my parents left me. Therefore, the career of a physicist did not please me. And now I work in the investment business. Everything would be fine, but somehow we talked with parents about what they are doing now. It turned out that after 20 years of work, they came from theoretical science to practical. And it was here that they encountered a very banal and simple problem - how to make a useful and marketable product for a consumer from a scientific discovery? But first things first.

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In order not to bore you with long, albeit colorful, stories, I will go straight to the point. In the scientific group in which my parents work, new material was developed. No, this is not graphene, but also very interesting. This is a transparent organic conductive film with a thickness of 5 to 25 microns, which has a very high sensitivity for measuring temperature, pressure, humidity and deformation. The high sensitivity of the film in comparison with classical metals is inherent in the nature of the material itself. It is caused by a soft crystal lattice, which can be deformed much more strongly than the lattice of inorganic materials, and the response of electrical resistance is significantly higher (compared to metals).
In addition, the Seebeck effect is observed in the film.(thermoEMF). This effect in films was discovered relatively recently, incl. it has not yet been fully studied and optimized, but as a first approximation, the following is obtained:

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Rin = 40 kOhm (different for different types of sensors)
Delta T = 10 degrees C
U = 500 μV
I = 500/40 000 = 0.0125 μA

Film thickness 25 μm indicated since it was for such a measurement data. Theoretically, it can be minimal (about 5 microns), but then the question arises of the thickness of the contacts.
You can also use the properties of the film in flexible electronics

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The use of films in flexible electronics allows you to get away from the problem of combining organic and inorganic materials. Due to the organic origin of the film, it is very easy to apply it to polymer organic matrices (the Young's modulus in this case will be of the same order), which increases the strength with respect to classical solutions based on metals.
In addition, due to the flexibility of the film, it can also be used in the textile industry, namely by stitching sensors directly into clothing.
All technical calculations and links to articles will be below. But this is all in theory, but what in practice? Where can all these wonderful properties be applied? The first thing that came to mind was medicine. I forgot to mention that the film is completely biocompatible (there are corresponding certificates), this means that the film is not rejected by the human body. Why medicine? It's simple, parents work in Europe, and here most of the money is in this sector. But the crisis began, and funding was frozen. By that time, there were already developments. For example, a device was developed for measuring intraocular pressure using a contact lens, the matter remained small - wireless transmission of the recorded signal. But there is no “electronic engineer” in the team and a lot of problems follow from this. There is no funding, so you can not hire a specialist on the side. So it’s impossible to bring the product to the “box” without an external development order. Local doctors say that measuring and monitoring intraocular pressure is very important in determiningglaucoma at an early stage, when it can still be cured. I am not a specialist in this field, incl. No comments.
The pig eye was used in this experiment, I hope that animal advocates will not be offended in their feelings by the picture below.

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Next was the idea to develop a system for monitoring human activity, capable of taking on-line all the main indicators: pulse, temperature, pressure, respiration, movement, etc. But again, everything came up against electronics, and let's say the signal output to the smartphone via bluetooth with the ability to transfer data further over cellular networks. I think it makes no sense to write the scope of such solutions.
Heart rate sensor. Laboratory development. Yes, all this is already in one form or another, but do not forget about the unique properties of the film, such as biocompatibility, flexibility, low cost, sensitivity and ease of use.

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Ability to measure breathing:



Laboratory sample of the device. The film is installed here.

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But it was decided to start with more local and simple devices - the endotracheal tube was modified. The principle is very simple, a small strip of film is glued onto the inner surface of the tube, which very accurately measures the pressure of the air entering and leaving the lungs. Such a system allows avoiding damage to the lungs due to too high pressure in the vital support system.

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Around this stage, I learned about the work aimed at commercializing research data. Naturally, I tried to find investors in Russia (the benefit of the specifics of my work allows, there are exits for both just wealthy people and owners of large enterprises), but none of those I met are interested in investing in medicine, which is generally very characteristic of all emerging markets such as Russia. And here’s what I’ve come to, there is a new interesting patented material, cheap to manufacture (in laboratory conditions 1 sq. Cm. Costs about 1.5 euro cents), this is on the one hand. And there are investors who are ready to invest both just a lot of money and a lot of money in production, but the production of the finished product, and not the film itself, is on the other hand. But the problem is that there is no product.
One of the ideas for starting work in Russia was to combine film and RFID tags. Those. creation of not just tags, but tags that can provide on-line information about temperature and / or humidity in each package / container (storage). Or biotags for measuring the "average patient temperature in a hospital" at the touch of a button. Another solution (proposed by one large corporation, but still at the stage of "interesting development"), the use of labels in automobile tires for measuring pressure. You can fantasize quite a lot about the combination of film and RFID technology, especially if you recall the effect of thermoEMF, which theoretically improves (?) The performance of passive tags. But the problem is the same, there is no person who could even connect RFID and film at least on their knees and show how it works. Not to mention
So we come to why I decided to write this post. Actually I found Habr in search of information on RFID. I honestly tried to figure it out myself, but I realized that all physics and radio electronics were too long in my life and I now get closer to concepts like IBIDTA, ROE, etc. Of course, I still had friends who didn’t go into business, but stayed in R&D, and we have already begun to cooperate in this area, but everything is moving very slowly and so far it is not a fact that it will end with something really interesting. But I really want the path from the laboratory to production to be as short as possible, and not drag on for several decades, as is usually the case.
Recently, I more and more like crowdsourcing to solve any problems. So I decided to write a post here. On the one hand, on Habré there are a lot of professionals who know how to work with their hands (more than once I was convinced of this by reading various articles) and maybe someone will want to try to make a sensor using these films. On the other hand, many of you work in industries where the use of films can be an interesting solution, both for introducing a new monitoring system and for optimizing existing solutions. And of course it will be interesting to hear your ideas on how to use such films. And if there are people from R&D who are interested in cooperation at the level of scientific groups, then I will only be glad.
In other words, I invite everyone to take part in one of the most interesting phases of the development of something new - to bring new material from the laboratory to mass production. And what the hell is not joking, if you get something interesting, then in addition to those potential investors, about whom I wrote above, there are always kickstarter and other similar resources.
Well, and a little more for a fantasy flight: the sensitivity of the film (size 1 sq. Cm with a consumption of 25 mW) allows you to measure the temperature change in an isolated room (room of 20 squares) when a person appears there. There were ideas to supply gamepads for PS and Xbox with sensors to measure the player’s heart rate and hand humidity, but they just released new devices, although if there are people from Sony or Microsoft, I will be glad to cooperate. Also, high sensitivity allows you to think about the use of films in inclinometers. This film is a synthetic material, which allows you to change its structure and properties (within the reasonable) depending on the goals. For example, slightly changing the structure of the film, we get a strain-sensitive sensor that stably works in a wide range of temperatures (from 140 K to 350 K). Or changing the structure a little more, we get a humidity sensor working from 10% to 100% humidity. There is no need to “dry” the sensor after use. And in the end I would like to add that these films are quite durable - some samples have been working for about 15 years, i.e. almost from the moment of their synthesis.
For other technical data and proofs, please follow the links below:

Links to some articles:
1. Ultrasensitive Piezoresistive All-Organic Flexible Thin Films
2. Highly piezoresistive textiles based on a soft conducting charge transfer salt
3. Linked Crystallites in the Conducting Topmost Layer of Polymer Bilayer Films Controlled by Temperature: From Micro- to Nanocrystallites
4. Direct micro-patterning of TTF-based organic conductors on flexible substrates
5. All-organic pressure sensor for monitoring quite large pressure values ​​with a high level of measurement accuracy

Disclaimer: as I already wrote, I am now very far from science as a whole, so if somewhere I didn’t write something correctly, please do not blame and give my comments in PM, I will correct it. In general, I am sorry to consider this article as a translation from a scientific language into a less ordinary one. If there are questions in essence, to Wellcome, I will try to answer myself, and if it does not work out, I will redirect them to competent people.

UPD 1: As I promised, I am posting additional material. Presentation with some technical details.
UPD 2: Do not consider it as PR, but because I received several messages in PM from friends of habrayuzer not having the opportunity to write here, I think it is right to leave my email for questions: i.laukhin at gmail.com
UPD 3:Dear habra people, unfortunately I did not manage to send / give samples of material to everyone from the first time. But at the end of the year I plan a second "distribution of elephants", incl. if someone is still interested write in a personal, comments here or by e-mail i.laukhin@gmail.com

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