47 min . Jun 15, 2026 . Engineering Materials Science and Engineering
In a world where clothing is constantly produced, purchased, and replaced, there is still a lot to learn about fabric. What may seem like an old, familiar industry turns out to be full of advanced physics, materials science, and engineering challenges. MIT Mechanical Engineering Principal Investigator Svetlana Boriskina develops new fabrics that can provide thermal comfort indoors and outdoors, resist dirt, and create color without dyes or pigments. She shares insights into exploring new areas of research outside her comfort zone, lessons from the textile industry, and what fabrics can teach us about nature itself.
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Svetlana Boriskina: Just think of it like waves in the sea right? If there is a small rock. A large wave will just roll over that rock like it's nothing. But if it were a small wave, it would scatter on that. So that's exactly what we are trying to achieve.
John Harrold: Hi. Today we have Svetlana Boriskina, who's a principal investigator in mechanical engineering, here to speak with us. Svetlana, welcome.
Svetlana Boriskina: Hi, John. Thank you.
John Harrold: So what are we going to talk about today?
Svetlana Boriskina: We're going to talk today about something very unusual, but something, you actually encounter a million times every day. And that's fabrics, textiles and garments that are made out of them.
John Harrold: That sounds really interesting. So why don't you tell us a little bit about how you got into to the idea of researching fabrics?
Svetlana Boriskina: Well, it's an interesting story, but also to most people, I think the idea of talking about fabrics may not sound that interesting, right? Because that's an old topic or perceived an old topic. Textiles have been with us for centuries and thousands of years. So people think of it as an old technology. And that's how I was thinking about it until about seven years ago or so. Because by training I'm actually an optical engineer and scientist and photonics, optoelectronics, advanced materials. So materials, we normally say things that are more advanced than fibers and textiles. But then a while ago there was this call from ARPA-E. They were searching for cooling technologies. And what's ARPA-E? ARPA-E it's a branch of Department of Energy of the United States. And they are focusing on advancing new technologies that are more ready for immediate commercialization.
Svetlana Boriskina: And more applied majors and fundamental research. And so the DoE supports.
John Harrold: Cool.
Svetlana Boriskina: So they were in search for this, commercialization of the idea technologies that would provide cooling capability. And they defined it very broadly. It could have been cooling on the building level. It could have been cooling on individual room level or electronics or whatnot. And well, we always need money, right? So we were thinking, what can we, propose for this specific call? And with my background in optics and photonics, I was thinking, okay, can we utilize radiation as a way to remove energy or prevent energy from going from one place to another to achieve cooling?
John Harrold: And while we're talking about radiation, right, a lot of people think about radiation as something like nuclear. But radiation is really just a way that energy moves, right?
Svetlana Boriskina: Yeah, it's just a way of energy moves as a wave. And that wave could be different.
John Harrold: Yeah. So light radiates, you know, microwave is radiation or just even the heat coming off of, of your arm. That's radiative.
Svetlana Boriskina: Absolutely. Yeah. Or from the sun or from the sun comes the sun. We see light. But also part of that energy comes as heat. We feel it on our skin. It's invisible, but it's absolutely real. Wave that is carrying quite a lot of energy, actually, for sunlight is half of the energy of sunlight is in that invisible part of radiation in the, inside.
John Harrold: Yeah, yeah. Because the the heat that we feel is the same as the light that we see. It's just all just different wavelengths.
Svetlana Boriskina: Yes, absolutely.
John Harrold: And this is known as the infrared?
Svetlana Boriskina: Well possible that we don't see is infrared yet. Yeah I will I said just not sensitive to that part. But our skin is and the same with our bodies. Indeed we also radiate infrared light not as much as sun. So that's why we cannot really heat the room by our bright personalities. But nevertheless, that's, heat loss or an opportunity to achieve heat loss from a human body through radiation. So what happens? Normally with textiles? They block that pathway. They trap radiation that otherwise would come from the naked skin. And they keep it close to the skin and that it does not allow us to cool down as efficiently as we would like to. That's why in the summer, people usually strip down to, as much as it can. But, the reason usual textiles do not allow us to utilize this channel fully because they absorb radiation. So pretty much it gets converted into heat.
Svetlana Boriskina: Now, conductive heat inside the textile and it stays close to the border. So we started thinking, okay, we want to achieve energy savings. So we don't cool down our huge rooms or buildings as much. If we can achieve cooling on the individual human level, because that's who is going to feel was it's cooler or not, right. The building itself doesn't really feel anything. We only have to maintain the temperature to keep people in the building happy. So if we can just alter their clothes in such a way that they share the energy more efficiently, if it's, too hot, and then maybe we don't need to reduce the, temperature overall in the room as much as we normally do. So we can save on our, electricity costs.
John Harrold: Right? So it'd be like wearing, like, a button up shirt, but it feels like you're wearing a t-shirt or a tank top. Or, like, not ideally, it would be like you're wearing nothing and you very efficiently radiate out through the textile, and that trigger chain can. Okay.
Svetlana Boriskina: Why regular textiles do not allow, for this functionality to be enabled. So for that to understand that, you need to look at the molecular structure of the textiles. And that's where it gets interesting and very advanced, not thousands of years, but like modern time. Because, all this absorption, this energy conversion into conductive heat is because of molecules that are vibrating and pretty much just trapping this light and converting it to heat. So it depends on what kind of atoms are present in a polymer molecule, because most fibers we wear, or all of them almost. Are made of polymers.
John Harrold: So polymers, that's like plastics, right?
Svetlana Boriskina: Some of them are plastics. Not every polymer actually is a plastic.
John Harrold: Right, right.
Svetlana Boriskina: So properly a plastic is a thermoplastic polymer. So that's a polymer that can be melted. And by melting you can make it into fiber for some plastics are not capable of doing that like cellulose for example, that is more traditional material, traditional polymer for textiles and fabrics where it's not a thermoplastic, so we cannot melt it. But nevertheless these are all organic, molecules which have different atoms in their composition, different bonds connected to atoms and the composition of those atoms. And structure of the bonds dictate what, frequencies of invisible or visible light are absorbed. And most polymers absorb very efficiently across the whole in infrared spectrum. So that means no matter how you engineer the fiber or textile, just because the material itself is going to absorb all that heat, there's not much you can do.
Svetlana Boriskina: But then we found, well, there are glasses that are transparent in the infrared, but we cannot really wear glass on our body. Right. We can use them in optical experiments, but that's not a good fiber making material because. So.
John Harrold: Well, I mean, imagine, you know, the goal of a fiber is to move flexibly, right? So there's this amount of motion that it wants to have and things that are very brittle, like glass or, you know, wood or well or other things, unless you, it, it would actually cellulose. So what is it now this is used to make fibers and that's, that's, what is it called?
Svetlana Boriskina: It's called rayon. It's regenerated cellulose fibers. It's actually very popular. New research direction in, sustainable fiber production. But glass, I mean, you can make glass fibers. They're just not good for wear.
John Harrold: Yeah, like fiber optics do that.
Svetlana Boriskina: Yeah, but it's not it's not going to. Right. You just get something very comfortable and cheap because you want to make it on scale. So.
John Harrold: So how did you connect this. Well your knowledge of okay, well I know that glass is transparent to these things and you're not very well, but these polymers aren't. And like, how did you. Well two things. One, well how did you connect those dots. And to how did you I guess believe that you could connect those dots.
Svetlana Boriskina: Well initially I guess I just refused. Ok, there was a group of us working on this. It's not just myself. And all of us wanted to make it work and, initially. So there are so many materials available, surely we can find something then the more we looked. We realized that's why it's so hard, because there are not many materials or any, almost that can achieve this functionality while also being flexible and abundant. But the rationale for looking for a good material was pretty clear, because the more different bonds you have, the more likely you will be absorbed across the whole, spectrum of infrared radiation. Because every bond has its own vibrational frequency and just bond like all the atoms connecting to each other.
John Harrold: Yeah, just like two carbon atoms connect. That's one size bond when you have, like, a nitrogen and, you know, oxygen that's a different size bond. And and they're similar sizes, but those sizes are close enough or different enough that it, it interact with light differently. Right.
Svetlana Boriskina: And they allow for different types of interactions. So it could be stretching. It could be rocking. It could be different types of deformation. And atoms are different in sizes and masses too. So you can think of them as a bunch of pendulums. Each of them moves at a different, isolation or frequency depending on its, mass and the length of the rope it's hanging on. Right. So if all of them would be the same, then you would only have one frequency, so that would be one absorption. Okay. Absorption line. But if you have many, many different pendulums, each of them are moving at different frequencies. This pretty much covers the whole spectrum and extinguishes the whole spectrum of infrared radiation that our body is trying to use to cool down. Right? So that drives us to the search of simple materials that only have one type of bond, maybe two types of bonds.
John Harrold: So you're looking for like the 1 or 2 pendulums that are going to be swinging at the right frequency to let all this heat out. Right.
Svetlana Boriskina: So you have windows outside of those frequencies where you have transparency and the heat can come out. And we found one material which is actually very abundant. It's thermoplastic, and we use it every day. Everybody does, just not for the purpose of wearing it.
John Harrold: Polyethylene?
Svetlana Boriskina: Yeah. So it's a material used for plastic bags. So every time you open in your plastic package that's most likely polyethylene or milk bottles made of polyethylene. So it's everywhere. It's actually the most mass produced plastic on Earth and cheap.
John Harrold: And cheap.
Svetlana Boriskina: Yeah. Yeah. Definitely. Right, right. So while, you know, even think about the cost. Right. Yeah. But it's very simple. If you look internally, if you have a capability microscope or some characterization tool to look internally, you'll see that it has only two types of atoms carbons and hydrogens. So it's pretty much long carbon - carbon - carbon - carbon - chains. And then hydrogens are like dangling over that chain. So that means there are only two types of bonds. So that not so many different types of vibrations to absorb. And when we measured it confirmed this, hypothesis. So there are very sharp absorption peaks and then big transparency windows in between. So there was also one problem with polyethylene.
John Harrold: Yeah.
Svetlana Boriskina: Which you can probably guess if you saw a plastic bag I mean it it's a plastic bags rip when they're pretty thin and when they're thick enough for the bottle, they don't really probably feel good to wear that too. But it's also transparent.
John Harrold: Oh yeah. That would be awkward.
Svetlana Boriskina: That would be very awkward. Right. So but so that was actually the biggest problem to solve for making textiles out of it. Yeah. Because the material itself provides this nice transparency. But then we needed to engineer it to be not transparent in the visible.
John Harrold: Well, don't they dye fabrics?
Svetlana Boriskina: It's not just that. That's one thing, but it also may affect your infrared properties because now you will be adding..
John Harrold: Oh, because dyes are made of stuff.
Svetlana Boriskina: Of course. It is organic molecules.
John Harrold: Oh yeah. Oh that's right. Yeah, yeah.
Svetlana Boriskina: And also another issue with polyethylene. It's actually very hard to dye near impossible. And that's why inside with respect we realized why it's not conventionally used in textile production because it's very neutral. It's impossible to attach anything to it. Again because of simplicity of the structure. There are no functional groups that can serve as receptors for dyes to attach to, because how you normally dye textiles, you just dump them in, water solution of those organic molecules, which are colorants. And then they attach, they find some, areas on the polymer where they can attach form additional bonds, and then they just hold on tight. Yeah, yeah. So polyethylene doesn't have any of the sides to attach.
John Harrold: So that's why just to I guess just to summarize, where we're at, you're looking for a new material that can be used for making clothes that are cooler, right? And looking at all the material. And you came across polyethylene and I assume that a material that is really hard to make or expensive probably wasn't going to work out anyway. So you're looking at all the material that was that was easy to produce, that had the infrastructure that could scale and do this. And you came across polyethylene, which seemed perfect, but it's transparent, right? It has the right pendulums, but they're also letting invisible light right. That. Yeah, that we can't do. And so this dye thing so so what do you do now that you have like we have a perfect material but it's just not going to work the way it is. But we don't want to change it too much. Otherwise the things that we're using it for. Right?
John Harrold: Is that's the stage where we're at.
Svetlana Boriskina: That is the stage. So we just needed to find the trick which would make that material, not transparent. in the visible.
John Harrold: Oh. Is that. Oh, it seems so easy to say.
Svetlana Boriskina: Oh, well, if you know how optics works, it's actually not that complicated. Okay. Because really, all white colors that we see, paper or anything else, it's, it is out of structural coloring. So it's just - it is out of scattering. There are many, many since it could be a roughness on the paper or individual particle in the. Chalk or anything. So what is happening is just light is scatters in every direction and gets all reflected back. So it's not a property of the material per se. It's more a property of the composition of that material on what length scale it's being shaped. And so you just need to shape it on the length scale, which is on the same order of magnitude as the radiation you are trying to scatter.
John Harrold: So you're saying that the, the colors that we see is just different light scattering or moving around, off of the object. Right. And that is a function of the shape of the object and the size of the light.
Svetlana Boriskina: Yes. And of course absorption lines. Yeah. In this case we say there are no absorption lines. So it becomes purely a function of incoming light. So what are the spectra. What is the spectral composition of the light. Yeah. If it's white we have like all the lines in it, all the colors hidden. And so now we just need to re-engineer our material on a small enough scale. And for visible light that means hundreds of nanometers. So nanometer is 10 to the power minus nine of a meter. So it's, it's really, really small. So like I'm almost 2 million nanometers 2 billion nanometers tall right. Yeah. So we can have hundreds, so that we can maybe have like up to micron. That's okay. So anything larger will also potentially make it white, but it will also start to interacting with infrared light because remember we don't want to scatter infrared light. We only want to scatter visible.
John Harrold: Oh so that makes it a little more difficult right. Because there's just a cut off. Right. Exactly. So infrared invisible light or right next to each other. Right. Close enough.
Svetlana Boriskina: So infrared, the peak of infrared, light spectrum that our bodies emit is about ten micron. So that's approximately like I don't know one fourth of, of the thickness of our human hair.
John Harrold: Okay.
Svetlana Boriskina: Small but the wavelengths of visible light is in order of magnitude smaller than that. Okay. It's below one tenth.
John Harrold: Yeah. Yeah. So we have this range of opportunity right. So it's ten times smaller.
Svetlana Boriskina: So that means we can actually shape something that it's large enough for visible light but too small for infrared yet relatively just then think of it like waves in the sea. Right. If there is a small rock the large wave will just roll over that rock like it's nothing, right. Yeah, but if it were a small wave it would scatter on the outside. Yeah. So that's exactly what we are trying to achieve.
John Harrold: So is that hard to do, like because I mean making polyethylene is seems pretty easy. But then you put this extra layer on top, like how hard is it to to work on that scale?
Svetlana Boriskina: Well, that's actually where I first realized the, how advanced fiber and textile industry actually is. And technology actually is because we take it for granted that I think we talked to the beginning and I never really saw how small those fibers are and what kind of precision is needed to fabricate them. And then when we realized what scale we need, we started looking. And it's actually very doable. And it's amazing at what scale and rate of production textile technology operates, and has been operating already for a long time. So we can spin kilometers of these fibers, which are just a few micron or tens of microns in diameter, and we can we examine bundles where we have hundreds of them in a bundle or whatever number we need by design in that bundle. So that makes you think it's actually fascinating.
Svetlana Boriskina: And it's an ultimate additive manufacturing technology that we had for centuries already without ever calling it that.
John Harrold: Right. Additive manufacturing is like a new thing, right? It was a past decade. And additive manufacturing. That's when we talk about like 3D printing. Right? Right. Yeah.
Svetlana Boriskina: So that means we are not subtracting from the material to cast it into a certain shape. We're adding to it. So we start with individual building blocks and then we build, build, build until we build a 3D structure in whatever form we need. And that's what we do with fiber. We start with a really tiny, slim fiber, and then we put it into model over yarn, and then we put them together in textile in different variations that can be done. And you pretty much have hundreds or thousands of completely different materials with different properties, which all start from the fiber. So anyways, that's where we realized it's actually very doable. It's a little bit on a small scale of a fiber, but still doable. So and we quickly, try to find somebody who can give us some sample to try, because initially it was just a conceptual theoretical standard which is optical modeling.
Svetlana Boriskina: We predicted that it's possible, but we wanted to see if that's real. That's where we realized it's actually very hard to find, anybody who can give you a sample of polyethylene yarn because they're not normally used to textile production. They're used in, more industrial applications like nets, fishing nets or geo-textiles, something you use in the garden. But you can use those are much larger fibers. So they were not good for us. And because they are large, they look like bulk they look transparent. So that's no good. But then we found some partners that helped us with initial prototyping. And that's where we realized if we really want to study it to, this idea to have an effect, to ever be implemented as any, commercial application. We really need to establish the whole pipeline of making these fibers and testing them.
John Harrold: So so yeah, it's like interesting because you say, well, we have natural fibers and we also have a lot of polymer fibers that they go through. And they make this. And okay, we have this, another polymer which is similar. We can just put it in the pipeline. But but it's actually much more complex like that. Like the current manufacturing of textiles is even more particular about each one of these different processing things. So even a small, well, small change, but a change in the material, even though it's same category material has to be processed differently. Right?
Svetlana Boriskina: That is the fact that, yeah, it can be in principle, if it's a thermoplastic, a standard equipment can be tuned to spin any kind of fiber with variations. But the biggest limitation was really we don't have this industry anymore in this country. So it's all very centralized. It's very localized in, Asia, in Indonesia, China, Bangladesh. And usually they make everything on such a large scale that it's very hard to produce like one bobbin of it yarn that is new because you need to stop the whole production and just do that one thing for you. And like who is going to do that? And so it's really hard to prototype to do something new because of this mass scale production. And it wasn't like that even a few decades ago, because actually we are sitting in Massachusetts and right here next door, like 40 minutes from here is it is Lowell.
Svetlana Boriskina: Which, which is a town in Massachusetts, which used to be the birth place and the Center of Innovation in textile industry for a couple of centuries before. Oh yeah. And then, everything just relocated at the end of last century, beginning with this one, everything relocated to Asia and all those buildings of original mills, empty. Well, now they're filling with other businesses. But we really lost this whole local industry that would allow for rapid prototyping intestinal and innovation. And now it's much harder to innovate in this space just because this initial, burden of overcoming the scale, you cannot start on a large scale.
John Harrold: So I assume there's many people around the country and in the world that is also doing research like this alongside of you. Right? So is this a common? Is this a common complaint from other researchers or from other researchers?
Svetlana Boriskina: Yeah, it's a big issue. We have people come in from all over from small companies looking for partnerships and opportunities to use spinning equipment that we now have, because we do a lot of it. Yeah, that's we cannot do anything until we do it. And thanks to State of Mass., well the Commonwealth of Massachusetts who helped us with some semi-industrial scale equipment, that's very rare to find. Literally you can count it on like fingers on one hand in this country. And then we acquired some smaller prototyping equipment so we can now try small on one fiber. And then we can scale it up to yarn and make a textile because, yeah. Without that, you cannot try anything. Also, you cannot usually you don't have enough material to go, to a big industrial extruder because that requires kilograms, tens of kilograms of material for just one run.
Svetlana Boriskina: And sometimes if it's a new synthesized fiber, that's actually a fun fact that I didn't know because I'm not a chemist, am I? So now we have equipment that can work with just a few grams of material. To me, it's very little like what is a few grams? And then it was that successful. We can go and spin it on a kilogram level. And then when you talk to a chemist that actually synthesized this new promising polymers and they tell them why it's just a few grams and say oh my God, Sveta a few grams is a lot, we cannot start or make a few grams usually start from much lesser material. Oh yeah. Yeah. So that eliminates this gap of innovation that you really need, fabrication capabilities on different scales to try out first material to evaluate its opportunities. And on this and it can go into mass scale production.
John Harrold: So I'm just curious, what was it like going from innovative materials and thinking about optics and, and all the stuff that you're good at and then realizing that you need to manufacture this, even on a small scale. And the best thing to do is build it in your lab. So then you had to learn how to make how was what was that like? Like turning on this machine or building this machine for manufacturing, you know, going from the place that you were before into this new, new type of work.
Svetlana Boriskina: It was a big step. Maybe now, thinking back in the right respect, if I knew how hard it would be, maybe it would give me pause. But, I think it was a great adventure. I don't regret going on that path because it brings up so many things you never thought about it. So say you get an equipment and then you realize, well, it was a very expensive equipment, but then it's almost as much to just install it and run it. And you never thought about it. You never saw how many hook ups you need to connect water, air, electricity. What's not to find your own large enough to operate it? And it's just like one thing after another, after another. And then you realize you need some additional auxiliary equipment to run it.
Svetlana Boriskina: But it also, I think, changes, the way how you think about innovation and it forces you to, innovate differently, knowing like everything that comes down the line, some early decisions you can make that will terminate, maybe some materials or, take you on a different path because you now understand, like the whole complexity of this topic. Yeah. It was fun. Yeah.
John Harrold: I think it's like a rabbit hole is the deeper you go, the more exciting it gets. And that's one of the things that I, I really love walking around here at MIT is you see a lot of people building stuff, like they're just going and doing it and taking those that that extra step to applying things. And it's it's a nice I don't know if it's the attitude around here or just some of like maybe the people are doing it as a lot of momentum of like, let's build it ourselves and make it make it happen. Is there a lot of support for this here? or were you trying to learn on your own how? I guess, how did it feel like some of that first steps of like solving some of those problems of the hookups and the finding the space and all that?
Svetlana Boriskina: A little bit of everything. So I had to learn a lot by myself. But of course, you learn by asking others. And that's something I had to learn to do more, to reach out to a broader range of people you never normally think of talking about. And everybody knows something in some area more than you do, right? So you can always learn from people and, just this culture, like you said, where people delve into science without maybe even fully understanding that is what drives innovation. Well, that's fun, that's, that's the fun. Yeah. You just need to switch the mindset, because I have a long history of working in different institutions before coming to my team. So I originally came from Ukraine, from Kharkiv Ukraine, and that's where I studied optics, photonics, and even some large like radio antennas for different types of radiation waves.
Svetlana Boriskina: And then I worked for a while, as a postdoc at the University of Nottingham. And then, when I first came to this country, I was at Boston University. And I mean, they all had their strengths and interests in research, but I don't think any of them had this same culture of just jumping into new areas and like, using the community around you to learn and advance new directions.
John Harrold: I'm so glad you want to be here. So we get to talk about this stuff. Yeah. You know, I, I did a little bit of homework, and I had the chance to to hop into one of your classes and there's just something that I'd love to talk about. If we can move on a little bit or come back to something we talked about the the dying. Right. So talking about how it's really not trivial to to die, these fabrics and all these types of things. So can you talk a little bit about the difference between natural and synthetic fibers and the dyeing process and how that, that kind of is a little bit bigger than it was a lot bigger to me when you presented it. And so I'd love to kind of like, you know, get the story again. Right? Yeah.
Svetlana Boriskina: So people normally saying that natural textiles, good. Green and fuzzy. Right. You know, good for the planet. But once you fully understand what it involves to make a textile out of a natural material, you realize this story is not quite that simple. So it's a lot of work processing. Not only dyeing but also how you go from an initial material that is not thermoplastic. So you cannot simply melt it. It's not water soluble. So you need to somehow convert it into a form that you can make fiber out of it. Right. And so a lot of this is heavy chemical processes involving high temperatures, multiple chemistries, multiple wash in between chemistries. So just to make a fiber itself or make a yarn out of fibers that nature already made for us, like from cotton, wool or as a natural materials. But then dyeing it is another story.
Svetlana Boriskina: So you need to find that I dyeing that throughout history there was a big search, for natural materials. And now we are mostly using synthetic dyes and how to apply that dye that also uses the high temperature, some additional chemistry that is needed to make that dye attach.
John Harrold: And because dyes have changed a lot, right. Like I remember when I was younger, my parents would tell me about, oh, you got to make sure you the colors will wash out of your things and they'll fade. But now I don't even think about it. And clothes I've had for, you know, years and years and years look pretty much the same as when I first had it. So. For the most part. Because that's that's different. That's the dye, right? Because those are the synthetic dye.
Svetlana Boriskina: So guys, come back to but also it's processing because initially there is some dyes. It needs to be removed. Not everything attaches. So that creates a lot of waste water because you've done properly. And you then need to wash it during production enough times. So there is no more washing out after when you actually get it to wear. Right. And that is a lot of waste water. So it's literally thousands of liters of water to make one white T-shirt, believe it or not. No. If you yeah, if you color it, it's going to be even more because it's throughout the whole cycle. You need to wash your original material multiple times. Then you need to wash it after you leave it or knitted. And then if you colored additional water usage and then all that water goes into rivers. And that's actually, what was happening here in, rivers in Massachusetts when the industry was still here.
Svetlana Boriskina: If you look at archival photos, they were all yellow. Blue. Well, not normal blue colored, blue, red, all sorts of very unnatural bright colors. Now they're all clean because there is no more contamination. Plus we have clean facilities. But now in Asia, a lot of rivers look the same way, so it's terrifying. There are huge rivers and they carry enormous amount of this excess dye. And other chemicals that it is out of fiber and textile production. Is it really difficult to collect that water and like pull the dye out? Is that why is it just a waste? It's expensive. It's expensive. So people are now moving. There's a lot of regulatory pressure like a lot of countries. Obviously nobody wants that in their backyard. We didn't doesn't mean China, wants it. So they are pushing back on that too. That increases the cost because it's much easier to just wash and dump the wastewater.
Svetlana Boriskina: So that puts the pressure on, producers to change the practices to have more closed cycle. And in some cases, you can recycle this dye, but it's just the cost ultimately. And textile industry updates on such small margins, actual producers like brands may be making a lot of money, but people who are actually making and dyeing these fibers, they don't have much leeway. So it's in many cases just economic decisions.
John Harrold: And I guess that leads me to another kind of question, right? Because I mean, everyone's, you know, for the most part had the experience of picking out clothes either to wear to buy or you're looking at things that you like. So now that you have this intense knowledge of both the industry and the technology, how does that affect, I guess, how you pick clothing or look or how you look at clothes?
Svetlana Boriskina: I think it didn't, but because what I value in clothes and many other items is durability. Maybe it's my childhood background growing up in the Soviet Union, I don't know, but I really like when things are durable. I think that's the best way to achieve sustainability, because if you have to remake something many, many times, that's not very sustainable. If you have something that lasts for many years and maintains its, underlying function and material properties, and maybe even at the end of its life cycle, it can be reused for something else. So I'm pretty conservative, have always been with my clothes, but now that I understand better, like why some materials somewhat durable than others and but new, understanding for me was that synthetics are actually, if you properly do the analysis of the cycle, they are not actually bad. So I don't know, maybe some people will hate me for that.
Svetlana Boriskina: But you don't. You shouldn't feel guilty. wearing synthetics. Because actually. Well, we see one of the problems they have is depletion. Depletion of fossil fuels because most of them come from fossils, but they don't have to. Now, they are new synthesis process that you can use sugarcane, for example, to make polyethylene or polyester. So it's more expensive. But if needed, the industry can quickly adapt and make the same thermoplastic synthetic materials from natural products.
John Harrold: And I hear, you know, a lot about materials and clothing and garments made from 100% post-consumer recycled materials, right. Like this. So your your polyethylene material, there's a lot of it around that's been made. Does does your process lend itself towards something that can be post-consumer recycled.
Svetlana Boriskina: Absolutely.
John Harrold: The post-consumer recycled. So there's two types of well maybe more. But there's two main types of recycling. One is like I have a bottle in my hand, I use it for a bottle and then I go recycle it and become something else. But then there's a lot of other things where I've made a bottle, and then there's some scraps and I'll take that and recycle that. So like, industrial recycling is much easier to do because it's much cleaner but post-consumer recycled where it's gone onto a shelf and it's gone into my house. And then I've put it out the curb. That type of post-consumer recycled material that's a little harder to use,
Svetlana Boriskina: much harder. And several reasons for that. So one is and just collection, right. How do you collect it when it's distributed all over? Then in what shape it arrives to? Recycling may be so dirty you can no longer use it. Or maybe it's very degraded because it was in the sun for too long. So the polymer chains are just broken by radiation. But another important fact that, especially with textiles, is most of them are made from a blend of different materials. So is it a purely cotton? right? where polyester and cotton is mixed together, or some other mixtures. And the most common mixture is spandex and say polyester or spandex and cotton, because any elastic, garment that we wear has that spandex core that makes it elastic, it's only 5 to 10% of the total mass of that garment, but you cannot remove it.
Svetlana Boriskina: And to recycle spandex, you need to use a completely different process than recycle polyester or cotton. So mechanical separation is not an option. It's going to be so expensive. So chemical separation is possible. But you need to have more chemistry and high temperature and all that. So it's not practical. So that's why most of textiles are just, discarded, burned in some cases, to recover energy but not really recycled even though individual ingredients in them are fully recyclable. But once you put them together, you can no longer recycle. And when what you mentioned, you see, products advertised as being post-consumer recycled, that's actually in most cases it would be bottle recycled into a textile, which is on one hand, what is a good thing? At least it's used once more. But think of it, you could recycle it to a bottle again and then again and then again.
Svetlana Boriskina: And if you decide to do textile, that's pretty much the end. Then at least at the current technology. Yeah. So that drives importance of thinking. How can we make textiles more material so you can actually recycle it as a whole. And the assumption that our technology chiefs we now have elastic polyethylene variety and non elastic. So if you put them together you can have a fully recyclable. No. But also you need to make sure that it doesn't degrade right. Because if after way it's so dirty yet you can no longer recycle it without some additional cleaning, that's also not good. So that's where materials that are stain resistant are super important. And again, polyethylene is one of those. The reason you cannot color it is because nothing attaches. You cannot stain it. So that's another advantage of that material. But it's more general.
Svetlana Boriskina: It's not like there is only one magical material that's good, right? For different applications there may be different material solution found. Nowadays, as long as you understand underlying principles like what is the properties of the material you need to look for is that properties are going to be bundled with some other properties. So the material that's like its grip, like one is what's one you improve, the other one you degrade. And also what are underlying, engineering principles. So materiality maintaining properties so you can still recycle it. And as I said this you need to be able to trace in the recycling. That's more like regulatory rather than material. But in many cases in order to recycle into like shoes or textiles, you need to be able to trace the whole history of that material. And that is very hard.
Svetlana Boriskina: If it's came from some waste you have no control of, like, what do you do about it?
John Harrold: Yeah. So I guess that some those are some interesting problems or challenges coming up. So are there are there any other challenges that you can think of that are really relevant to this industry, some future things that you're looking to work on or that the industry is talking about trying to solve?
Svetlana Boriskina: Yeah. So this amount of waste is obviously an important problem, not just for textiles for anything, but because textiles are produced by billions of garments a year. It really is a problem of waste. So Massachusetts, for example, bans discarding of textiles. You have to recycle them. I wonder how many people actually know that because there is no enforcement. And for the most part, they will be reused as some industrial cloths, but not really recycled into anything. So another issue is people are looking for alternative materials, for making fibers and textiles ideally sustainable in the sense that they are abundant. Right. And can be converted by available, processes. And people are looking at proteins as well as cellulose based materials.
Svetlana Boriskina: But insulation in many cases, I guess is a problem with many industries, but with textiles in particular, because it's such a long history, people tried so many things. And for the most part people don't remember, they don't study history of textiles and they try again the same thing that was tried and discarded before. And also because it's so old technology, maybe there are no good books or papers like research papers, protocol and all this prior efforts. So I feel like there is a lot of movement, which is always good that people try new things, but it could be more efficient if they actually checked what has been done before. And worked more like with, informative guesses of like, what can you do? And another, not so much.
Svetlana Boriskina: Maybe challenge, but aspiration because when people talk about it once textiles, usually what comes to mind to regular person would be some electronic textiles or textiles at performance. Unusual function. So that's important. That becomes a challenge of integration. And recyclability will come down the line. There's a challenge to it because if you embed electronics, how are you going to separate it after. For the most part this imbedding electronics is still a big challenge in many cases. You see in research labs, Samsung is like just a glove or some garment that looks like some normal thing you can wear, but what you don't see there is like a lot of wires and some big equipment behind. And yeah, that is actually measuring responses or like doing something.
Svetlana Boriskina: So there is still a big gap to overcome to fully like pack it into something that's fully in the garment level rather than like attachments.
John Harrold: All right. Well, I guess I'm gonna I'm gonna put some pressure on. All right. In 20 years, what are we going to see? What's the future look like of of garments, of textiles in 20 years from now?
Svetlana Boriskina: That's a big, I guess, like aesthetics comes in cycles, so I'm not going to go there.
John Harrold: Yeah. It's true. I hope the 80s don't come back. But you never know. Right?
Svetlana Boriskina: But, I think just by necessity of generating, less, waste, we will have more recyclable materials. And this technology is awesome. Well, it always has been, but now we are alleviating the demand for specific functionalities and cooling. In the one that brought me into this field, I don't think it's still, it's still unsolved, right? It's still a big challenge to do it passively. You can use air conditioner or you can run some liquid inside your garment. But to do it fully, passively, we're still not quite there. And with, our research, we tapped into radiation. We now tapped into conduction because we can engineer the fibers to be very conductive. So you can remove heat more efficiently that way.
Svetlana Boriskina: But I think it is more to do because a lot of this, early research, they are not very practical to mass produce, even if they achieve cooling, like you see a tiny patch on somebody's hands showing, okay, this patch is cooling, but to make, the same technology on a scale of billions of clothes, we have nowhere close to that. So new colorants, are always of interest. So now there is a little bit of cycling back. Also, let's use again natural colorants. I mean, they may use. they may be useful for some applications. Not all. And I think overall drive it is for me intellectually. And I think it's useful for production to, to have multiple functionalities embedded into one textile. And maybe if you have a colorant that's simultaneously anti-microbial, feature or simultaneously coolant. Right. So then you can have fewer materials, cheaper and easier to fabricate.
Svetlana Boriskina: So yeah, to me ultimate challenge is how many different properties can you pack in the minimum number of ingredients in the textile?
John Harrold: It's really interesting. Looks like we're kind of coming to a time on this. So if people want to learn more about this work, where should they look? Do you have a course on MIT Open Learning?
Svetlana Boriskina: Yeah, we have a course on, MITx. I also teach residential course and that was actually also, interesting to me. When I started there, I realized there is not much information, so I needed to created my own knowledge piles, sort of. And it was initially very hard. Now that we have AI tools and like more accessible, I guess it gets a bit easier. But, there was little knowledge and I started building this course, and I wanted to try it out on the, public to see if there is interest. Should I even go further into that field or. It's so old that nobody cares. And then my first foray in that field was a course I offer during IAP. So it's an independent activities period. And here at MIT in January which is just like a short course.
John Harrold: Right. For a month.
Svetlana Boriskina: Yeah. Yeah, it was a short course just eight lectures for a month. And it's open to the general public. So like people in Cambridge, sign up and I expected maybe ten, 15 people I booked a small room and then 250 people say, wow, I was completely shocked. I was like, no way that there is such a big interest in such an old topic. So I had to book a much bigger room. I was scrambling, and, there were many people from just a, community of Cambridge asking really good questions, even though they are not experts in textiles. A lot of students, too. That's created the nucleus for the course I eventually developed as a residential course. And converted it into MITx. So I'm writing a book now, which is like the material textbook for the course material. So it was a much longer and deeper journey that I ever imagined will happen when I just started looking into, fibers and it all.
John Harrold: All right. Well, thank you so much.
Svetlana Boriskina: Thank you.
