Self-Healing Material

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This is a self-healing polymer. It's not sticky but it does stick to itself!
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[@SteveMould]

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[@aaaaaa-rr8xm]

1k views in 4 minutes, congratulations!

[@Godwinsname]

What's the deal with Patrick Stewart? I feared he died seeing those candles.. :o but he lives, luckily :)

[@julian-io5wl]

If this polymer is crosslinking at room temperature how can it be that there are stil functional groups available for the self healing process. Normaly you would expect them to react with other functional surroundig them. I can imagine that there are weak chemical bonds that are broken(maybe by UV-Light) and reform all the time and when two seperate pieces come into contact they will also form between them.

[@krekre001]

Using the phrase... self healing....i would expect that if you scratched it...the scratch would heal.

[@playerunknown6932]

From the first three minutes, it can be inferred how cold welding works in space; since there's no oxygen covering the metal, it allows the ion lattices to re-bind.

[@ruebancastro3189]

'I can't put metal back together.' then cuts metal and tries to put it back together. Scientific method at work. I love you Steve, make it tangible for us all.

[@tehs3raph1m]

just wasnt pushing hard enough... friction weld my guy

[@jaimedelgado7529]

Mercury

[@Twargan]

@@tehs3raph1m you're right and wrong. Welding metal happens from either heat or pressure. Or a combo of both. Something like tig welding would be 100% heat where as explosion welding is 100% pressure. Friction welding is a combination of both.

[@sethreign8103]

Some people just need a visual for what pressing two pieces of metal looks like for some reason.

[@superoxen]

Works for gold

[@loganh2735]

"Cold welding" totally blew my mind, and learning about it made it much easier to understand how a similar effect is possible here on earth. Awesome video!

[@DragonMan-tj3eg]

Holy shit you just made me realize that too

[@loganh2735]

@@DragonMan-tj3eg Glad to help!

[@chiryosaki5682]

Take a micrometer and tighten it with force. Also cold welded but not in a vacuum.

[@ykshay]

@@xenstence yes, I'm 5 days old and I know about cold welding, I can't believe these freaks don't know about cold welding bro, heh

[@KuraiKuroNeko]

Same, but now Sci Fi really feels more fictional, the more we learn about the true nature of space... imagine how many metal things could accidentally touch eachother in random situations, or the regulations created around the material plus alternatives potentially found that might replace metal, if we really became a space-exporing species. The possibilities are fun to imagine, for new-age Sci Fi media that features updated sciences!!!

[@Giraffemini]

Asking the question "Why DONT things heal or stick back" is such a great explainatory tool here! I wish some of my teachers had that way of explaining stuff back in the day.

[@kmktruthserum9328]

I highly doubt I would have paid attention to them still😂

[@Silly468]

This material repairs itself better than I can repair my life

[@williamm4366]

No you can do better, you can go into your local club of brazilian jiujitsu and never quit.

[@Silly468]

Ah yes, thank you

[@LargestBin]

True

[@autumn689]

Ngl this self healing material reminds me of skin

[@helloworld2409]

buddy a broken window repairs itself better than i can repair my life

[@SunderMun]

At Uni I did a project on self-healing materials, taking inspiration from Mussels. We were trying to replicate the self-healing properties by making an organometallic aerogel. Was really interesting but the scope ended up becoming multiple PhD thesises (no idea how it ended, if it has yet)

[@shinybreloom4027]

please tell me more

[@articxunodorseggnej8016]

Big brain clams

[@xsatsuki98x]

That sounds cool! I can't wait to read your publications soon

[@marcusrobinson1778]

@@xsatsuki98x he said he didn't publish

[@warfootages5578]

CAN I HAVE your Email ? Or any Contact information?

[@Isolanporzellator]

A part of our group happens to be working on exactly such polymers, so I am somewhat familiar with the topic. There are 3 main ways to get self-healing polymers (sorted from least likely to most likely to explain this polymer): 1) Simply using a highly elastic resin, which causes stress to deform the material rather than break actual bonds. Over time and sometimes with a bit of heating the original shape is restored. An example of this being used is the "scratch shield", which is a highly elastic clearcoat used by Nissan to give their car finish the ability to heal moderate scratches by itself. Clearly your material has bonds fully broken upon tearing, so this is not the technique that's being used here. 2) Separated reservoirs of unpolymerized monomers and initiators/crosslinkers/catalysts. These can be either capsules or vascular systems spread evenly throughout the polymer. Upon injury, the monomer spills into the cracks and comes into contact with the initiator/crosslinker, causing it to polymerize and heal the injury. An early example of this is the use of Dicyclopentadiene monomer capsules that, when released after an injury, are polymerized by Grubb's Catalyst through an olefin metathesis reaction (doi.org/10.1038/35057232). The healing process uses up monomer and thus can only be performed a very limited number of times. In case of a full tear, the spilled monomer would polymerize on the loose end. Once fully polymerized joining the ends would no longer cause the polymer to heal. It seems unlikely that this technique is being used in your material. 3) Reversible bond breaking and formation (Also called "Intrinsic self-healing"). Polymers of this type have specific functional groups that can connect and disconnect with corresponding groups in a reversible manner. After a tear, rejoining the ends causes loose chains to reconnect to each other, healing the polymer. Closed chains can also be opened and then rejoined to form new links. There are numerous ways to achieve this, some examples include: 3a) Reversible formation of covalent bonds, for example via Diels-Alder-/Retro-Diels-Alder reactions (DOI: 10.1126/science.1065879). Some chemical bonds can be reversibly broken and reformed. After joining the ends together, chains in both ends can break apart and recombine with chains from the other end, reestablishing covalent links. Usually, energetic triggers like heating or UV-light are required to facilitate the mending process. You did not use any such triggers, so this is probably not what you have. 3b) Reversible supramolecular bonding. I am quite certain that this is what makes your polymer mendable at room temperature. There are several interactions that can cause polymer chains to stick to each other without any covalent bonding (ionic attraction, coordinative bonds, hydrogen bonds and π-stacking interactions). These can sometimes also be broken and reestablished at room temperature. You can imagine these supramolecular polymer networks to be like ball and stick magnet toys for children. Your sticks are short polymer chains with negative endgroups (ionic groups or chelating Lewis bases) and your balls are positive metal ions. The combination of both can form large networks of interconnected or entangled chains. The sticks can be flexible, but are not broken apart easily. However, the forces connecting balls and sticks are much weaker and so these connections can be rearranged with a relatively low activation energy, causing the material to stick to itself easily even after being fully disconnected for a long time. Even lower activation energies would be needed for hydrogen bonding networks (replace opposite charges with hydrogen bond donors and acceptors, H-bonds are significantly weaker than ionic bonds). An example for this is published here (doi.org/10.1038/nature06669). I think self-assembly via hydrogen bonding is the most likely explanation for the behaviour of your polymer, though of course I can't say for sure. An interesting example of an elastic polymer that sticks to itself but not other stuff is Parafilm, which is just a mixture of polyethylene and wax. It can't truly "self-heal", but it goes to show that even much simpler polymeric systems can show some of these properties. I just wasted an hour of my time to write this... oh well.

[@629Justme]

No you didn't. You are among interested parties. Well, I am. Have you posted on Quora? Another place for detailed answers.

[@hyperplayability6290]

Not a waste. Was very interesting to read :)

[@crackwitz]

This post needs to be... stickied!

[@coltongerber1879]

You did what I do when I see a video touching on some area of materials science I know about! Glad to know I’m not alone

[@psilovecybin5940]

You shared knowledge. No waste of time at all. Thank you very much thats was very informative.

[@rebecacedeno1856]

I think the mechanism that puts the pieces back together is supramolecular interactions. The polimer chains are functionalized, at their ends there is an additional bonding, like a puzzle piece. So when you put them back together the puzzle pieces at the end of the polymer chains meet the other puzzle piece.

[@fedormedin8861]

Can it be a 2d polymer? Two polymers reacts not only on ends but on long parts of molecules

[@supercuriousbrain]

Great analogy

[@nathanaelvetters2684]

Yeah. The selectiveness of the reactivity is interesting though. It needs low activation energy, doesn't react with simple ions or molecules like from air or other surfaces, but very readily reacts with the end of another polymer chain. It really must be like a puzzle piece with a specific shape, but then what keeps some oxygen atoms from coming together and taking up part of the open reaction site, blocking another polymer chain from bonding there?

[@eeurr1306]

@@nathanaelvetters2684To actually find out, wed need to calculate the electromagnetic fields with 100% detail.

[@AutistiCat2406]

Yeah but that means repeated use can make it worthless because itll all bond back together like a normal polymer at some point

[@Rappid_]

i have no clue what this man is saying but also understand it all in perfect detail

[@MadeInFranceASMR]

So is this like an atom-level Velcro?

[@7evYT]

YES!

[@TheLouisph]

not really

[@Eznet089]

How are these sub comments so different lmao

[@7evYT]

@@Eznet089 Most likely because every individual believes their opinion is the right one. 😄

[@CanIHasThisName]

@@7evYT In this case it's down to how strictly you want to follow the definition of each thing. Velcro doesn't really bond, it hooks.

[@petergoestohollywood382]

“Cold welding” doesn’t actually have to happen in the vacuum of space. From experience I know that if you polish two quartz glass plates very flat and smooth and then stick them together, they will permanently bond as well. It’s pretty awesome!

[@calipete]

This I would like to see! I've never heard of that.

[@gtijason7853]

@@calipete I've been able to Lap 2 copper heatsinks so "flat" in terms of the bottom surface of one and the top of the second that they transfer heat as good or better than with thermal interface materials. I'd say what happens would be called "Wringing" The phenomenon you speak of is routinely used to test the flatness of precision gauge blocks used in metrology: their ability to "wring" together both confirms their flatness specifications and is useful for storage, when a very light film of oil enhances the wring - and thus keeps corrosive environments away from the calibrated flat surfaces when the latter are not in use. Wringing is thought to be a combination of . . . 1. Molecular Attraction - accidental cold welding or, as Richard Feynman put it, when the interfaces between like materials are very flat, there is "no way for each atom to know which block it is in", so the bond across the interface gets more and more like the normal molecular forces holding the lattice together the flatter the interface 2 Suction - i.e. the blocks have expelled air from between them and air pressure helps force them together 3 Surface Tension - From any water vapor that gets caught between the blocks.

[@Meme-2038]

Cold welding is with metal, you said that happened with quartz without a vacuum. Quartz is not metal, it is a crystal

[@janvisagie231]

@@Meme-2038 I thought glass is amorphous not crystalline.

[@FaeAstray]

@@janvisagie231 Quartz and glass aren't the same.

[@randomstuffloool]

Props for the cameraman for going monucle size and recording the split

[@liandoaethend2403]

This teaches better than the chemistry class in my school

[@collinandersen3369]

You don’t know how long I’ve been wondering why metals don’t self heal. I asked this to one of my metallurgy professors and he acted like I had asked a stupid question and blew me off. Thanks for finally scratching this irritating itch!

[@keykilla78]

Must not be a very passionate professor then, either that or he didn't know himself and didn't want to admit it. You'd think they'd be exuberant to have the opportunity to explain the finer details of their field of expertise to a genuinely curious student.

[@KaliTakumi]

Willing to bet he didn't know the answer and thought it was a silly question to wonder in the first place. Oh how wrong he'd be

[@elevatedaspirations]

@@keykilla78 not everyone can be perfect at their jobs

[@danieldimitri6133]

There are actually videos of microscopic gold wires self welding in microprocessor production or something to that effect.

[@jondo7680]

That's why stupid people are happier. If you would be to stupid to ask this question or if you would be that stupid professor you would be happier than knowing how stupid that person actually was to you.

[@miriamrosemary9110]

Thanks for explaining why things that are broken apart and not sticky don't self-heal/weld! I never knew that! And also that polymer seems really cool and probably has tons of applications :)

[@purplepowerranger23]

I immediately thought of resealable food packaging

[@sphygo]

It does indeed. It's called self-fusing silicon tape and it's used mainly for pipe repairs and thermal/electrical insulation in areas where temperate or moisture makes regular adhesive struggle. Only downside is how hard it is to remove afterwards since you can't just unwrap it like tape, it has to be cut off.

[@frailvoid5844]

Yoo you’re right about the many applications like I just thought if they made condoms with this material it could save us a lot of trouble and maybe even spare some of us from the agony of existence

[@navster100]

@@frailvoid5844 it would be really hard ot get off after

[@2lefThumbs]

@@frailvoid5844 yeah, but you'd have the more important agony of tearing the damn thing off

[@teolopezpuccio739]

I may have experienced a self-glueing sticker once. This vid left me thinking if it was something similar. It was in an airport, a self-service baggage drop-off station automatically printed the long paper strip that you attach as a tag to your bag, with its identifying information. I remember the tag had one printed paper side, and another plasticky side that surprisingly didn't stick to your hands but glued firmly to itself when you bent it around the handle of your bag and made it touch itself. I remember being baffled that it didn't feel like the familiar adhesive side of a sticker at all. It didn't stick to the handle of your bag either which made it really convenient to detach later without leaving residue. Has ayone else ever come across this?

[@nguyetha7280]

Well at first, i thought this video is gonna be about mental health, how to heal ourselves and things like that. It turned out to be about real self healing material, and the way Steve simply explains and provides scientific information about it was just... interesting :D the content was not what i expected it to be, but i watched this vid till the end and learn something new, thank you.

[@BlackWolf42-]

Steve, when you join those two pieces together, is the reaction endo or exothermic by chance? You probably won't be able to feel it but a FLIR camera may show if it gets warm or cooler.

[@SteveMould]

Really good question. I might give that a try. Need to find my FLIR. The issue is I push it together with my fingertips which would probably swamp any slight changes in temp.

[@iangabriel5536]

@@SteveMould If you do, please update us!

[@Lishtenbird]

The process did remind me of metals getting welded back at high temperatures. But surely if (low enough) pressure moved the melting point to room temperature, this would've been noticeable in general use...

[@elliotmarks06]

@@SteveMould it also may be hard due to heat from friction...

[@edwardlees4585]

@@SteveMould Can you push two ends together with two wooden spoons or plastic tongs to avoid heat transfer?

[@JohnBaleshiski]

Love your humor of putting up a Patrick Stewart (fixed) shrine. You are fantastic. Thanks for regularly making us smarter.

[@aneeveewhohasinternet1871]

This guy is amazing lmao

[@BirdThatEatsPrometheussLiver]

Humor? /j

[@ehsanalmassi453]

I thought he had died and I quickly rushed over to google. He is not dead

[@nipun108]

@@ehsanalmassi453 yeah same. This joke confused me, lol.

[@tjenadonn6158]

@@ehsanalmassi453 Bold of you to assert that Patrick Stewart is mortal.

[@isadorah4969]

I used to always ask myself as a kid why cut things can't be put back together. Then I graduated at Chemistry but never realized how obvious it is LOL Prob because I work with water so no time to think about materials anymore. Thank you for pointing it out! This self-healing polymer is indeed very interesting

[@cocobos]

The quality of this video is marvelous!

[@NathanielCoran]

4:41 Sorry to have to correct the science here, but I think you'll find that a Polymerization reaction is actually when you send two or more monsters from your hand or field to the graveyard in order to special summon a fusion monster that lists those monsters as fusion materials from your extra deck

[@MexNoir]

shit he's right

[@Dexuz]

Unexpectedly expected comment.

[@humphreywolfe]

*Yu-Gi-Oh Master Duel moment*

[@PixelionRules]

Yes.

[@Hdx64]

I ritual summon a like for you, put a card facing down and I'll end my turn

[@Somethingcorporate99]

This is really interesting, I have "self healing" cutting mats for cutting fabric on and always wondered how they were self healing

[@jek__]

I believe those operate by a different principle- Self healing cutting mats are basically super dense and short brushes, so when you cut into them your blade goes between the bristles. It's less that they self heal and more that they avoid being cut in the first place

[@ivan_valerian]

@@jek__ I dont think that they're self healing at all even, cause when you bend the mat in the opposite way, you can see the creases and cut on the mat itself

[@ErisApplebottom]

@@jek__ thats cool, i want one

[@deletedddddddddd]

self healing mats dont actual heal, theyre just dense plastic that when cut it shouldnt leave ridges but they usually do...

[@makosen]

Majin Buu paper

[@pingipingipingi]

Have stopped the Vid. to write this because iam so amazed!!! Your style to explain is BRILLIANT 👏

[@gemmibear]

Fantastic explaination, even if you aren't sure. I was trying figure out why I'm able to puncture a film on a bottle of insulin so many times without destroying it. Easy to understand and funny, too. I'm a fan. Thanks!

[@dwo356]

It is so awesome that you anticipated the question of what would happen in a vacuum when discussing cutting a metal. It was the first thing that popped into my mind and I'm so thankful I didn't have to ask or look it up. Thanks!

[@shinesunarjo3638]

Thats what makes him great

[@LGreenGriffin]

I typed the comment, thought to myself, "Wait, he'll probably address this," and then an astronaut appeared.

[@benjaminsmith3625]

It's left me wondering about non-oxygen atmospheres though!

[@scottb9997]

If you do want to go deeper the process is called cold welding

[@tissuepaper9962]

@@scottb9997 yeah lol cold welding was my immediate first thought when he asked "why isn't metal self-healing?".

[@jonathanCRoberts]

You're obsession with Patrick Stewart is so... understandable and relatable. Thank you for sharing this passion with the world!

[@ommsterlitz1805]

It's more like a passion for Jean-Luc Picard

[@Grandwigg]

Sir Patrick Stewart is responsible for my Earl Grey addiction. It's nice to see kindred spirits. (Also, the Captains series interviewing the actors was amazing)

[@horacegentleman3296]

Only if you pretend the Picard series isn't real.

[@daltonwatson2058]

Sir Patrick Stewart's favorite cartoon is Beavis and Butt-Head.

[@canadiankazz]

Where were you when I was failing high school chemistry?! You explained things much better than my teacher ever did.

[@101perspective]

I used some of this self-amalgamating repair tape on a damaged carpet cleaner hose and it worked really well. It's kind of spooky even how it works. It's so different from what we are used to that when you first start wrapping it around the hose you think there is no way this is going to hold. Yet, seconds later it's like having a brand new hose.

[@lidarman2]

I use a self-amalgating tape all the time at work and yes, you stretch it to activate it. It actually does a great job sticking to itself when you do it right. And to float a ship in a gallon of water you simply make the container the same shape as the ship so that a thin film of water floats the ship up to the draft height.

[@Validole]

You just need a really small ship. In all honesty, I somehow doubt it would work? A gallon of water would need to be raised very high to counteract the force of the ship. If you made such a container, the ship would simply settle to the bottom of the container and push out all of the water.

[@bismuth7730]

Ship could only float if it displaced the same weight of the water, so the ship would need to weigh just as much as a gallon of water.

[@lidarman2]

@@bismuth7730 The ship can displace the weight of the ship in water with only a gallon if the container the ship is in is strong enough and can fit snugly against the ship. Here is how. Take the snug fitting container (Which has a height of the draft of the ship and fill it with water. Now place the ship in the water. It will displace the weight of the ship in water and float with a small amount of water between the hull can container. The rest of the water displaced will overflow the container and be gone. Now if you remove the ship, there will be hardly any water in the container. You will get the same result if you just start with that small amount of water. One does not have to literally displace the weight in water, one just has to effectively do it.

[@saltananda3227]

@@Validole the container would go half way up the ship, be perfectly formed to the ship (but allow a slight gap evenly around), and sealed airtight. The pressure of the ship would be evenly spread upon all the water encapsulating it, therefore it wouldn't sink or hit an edge unless an external force was applied. Basically a "shell" surrounding the ship with a thin layer of water.

[@2869may]

@@saltananda3227 Can you elaborate on how the "sealed airtight" part works....?

[@Charles_Snow]

I've always wondered what makes something "self healing". Ever since I bought a self healing cutting board for crafts. I'm not sure if it's made of the same material. Thank you for another amazing video!

[@TimothyFish]

Self healing craft boards seem to be rubber glued to a base that is hard to cut. The rubber doesn't actually heal, but the slits don't remain visible because the base keeps the rubber in place.

[@axuwu6939]

@@TimothyFish This should be easy to test out by making a cut then pulling at the sides! I want a self healing cutting board to try this now. For science!

[@JungleLibrary]

Self healing cutting boards are different, they basically compress the surface rubber so that if it's cut, the compressed rubber expands to fill the gap, but it only works so many times

[@jasperfk]

@@TimothyFish I vaguely recall some self-healing cutting boards that have micro-tubes of epoxy resin which ‘heal’ (fill) lacerations in the cutting surface, too.

[@maxnovakovics2568]

@@TimothyFish i knew it wasnt self healing when i saw the one on AvEs bench

[@IAmEric85]

They have this issue in space, where oxidation is very slow to nil due to lack of oxygen. Tools and stuff get fused... cold welded mentioned at 3:00

[@EthanD19]

Self fusing silicone tape. It is a rubbery substance and have worked with it a lot it’s great for everything on a car (wiring looms mostly for me). It’s water proof, air tight, high temp proof, non conductive, high pressure resistance, oil proof and leaves no residue when cutting it. Perfect for wiring looms (near where oil can leak or near very hot components), coolant leaks, air leaks, oil leaks, wiring wrapping, waterproofing connectors. Good stuff a bit better then duct tape BUT doesn’t stick to any surface but itself which is a benefit but a pain to wrap in a circle around itself in a tight space.

[@luci4087]

0:44 the “shrine” to patrick stewart. lol nice.

[@jmmahony]

Unintended cold welding in space also happened on one of the Gemini missions, when they opened the hatch for a space walk. As the hatch hinges opened, the scraping between the two metal parts of each hinge cleared away the oxide layers enough so that the two parts of each hinge started to weld together in the open position, so when the walk was over they had a hard time closing the hatch.

[@HawtDawg420]

Interesting! Unfortunately though, a quick Google search led me to articles that say that while cold welding was originally thought to be the culprit, a SPRING that failed to compress was the real cause of the hatch not closing. Still, it's an interesting phenomenon that I had no idea about.

[@melody3741]

Nope - it was a theory but not what actually happened.

[@paaaaaaaaq]

@@melody3741 Bang! Debunked! Hang on a second, what happened then?

[@EazyDuz18]

space is fake

[@Jupesonshrooms]

thanks for the invention idea my friend much love 💡

[@jakupeli4959]

i learned so much from this video, this is amazing

[@10yrs.istillcantthinkupawi11]

Dude I am actually blown away and baffled by the oxidation explanation. I just assumed that when you cut something (specifically metal) all the particles just naturally start to reorient to compensate for the new gap in space that is created and so when you would try to rejoin the two points they would just naturally start to repel because of the new orientation of the atoms would cause electrons from one piece to be repelling of the electrons on its counterpart and so on and so forth... I really want to see two solid pieces of metal rejoin into a singular piece in space right now oh my God that sounds amazing

[@joeshmoe7967]

Or here on earth in a vacuum chamber? I am hoping some youtuber tries this. I would have to see it to believe it.

[@beeble2003]

There's no orientation. The electrons around atoms are in constant motion so, when you ionize an atom by removing one of the electrons, that positive charge isn't localized on one side of the atom.

[@hawq2483]

kzbin.info/www/bejne/ppLZoWmapdhpp5I

[@hawq2483]

kzbin.info/www/bejne/op-6cpieorGbrrM

[@wyattoutlaw2370]

I don’t think that’s true. Metal won’t stick to itself just because it’s in vacuum.

[@markusschnepf]

honestly, I thought the thumbnail image was clickbait. I DO know these "self healing patches" that have small pockets filled with glue. but this polymere is impressive and so are Steve and his videos

[@jam99]

I never go anywhere without self-amalgamating tape.

[@VulcaNtGoF]

@@jam99 Nor do I. I used to manufacture it, so I have literally dozens of pounds of the stuff in multiple sizes and colors.

[@Hiyori..]

I remember doing a similar thing with tape and also with clay

[@lgbthater]

These are the kind of people who give me hope for KZbin. Scientific content that is creative, informative, and actually gripping. Makes me wonder what my science teacher was doing 😂 Amazing job Steve!

[@humanistwriting5477]

I think this material is awesome, I am going to share this with my boys for sure! Just for engagement; Another cool thing about metal cold welding is that you can do it in the atmosphere! Obviously with gold, but also with oxidizing metals you just have to design the joint to push out the oxidized material as the material is pushed together But, even then there is an amount of time that you have to wait while holding it all steady for it all to weld together, it starts at random locations in a process called galling, and eventually becomes one solid unit. The amount of time is dependent on the temperature I find it absolutely crazy that there is amount of contact time required for the metal lattice to fully recognize that its one unit again!

[@takuma359]

big brain

[@AkiSan0]

well, as with crystallization lattices dont magically occur. ;)

[@takuma359]

@@AkiSan0 also big brain

[@DEtchells]

I used this stuff for ultra-waterproofing a fiber optic connection. It worked super-well. Here in the US, you can find the stuff under the brand name of X-Treme silicone rubber self-fusing tape. Very useful stuff, and it really does fuse to itself; once it’s together it’s a solid mass that you have to cut to separate. It takes a second or two, but you need to make sure you put it where you want it!

[@dickJohnsonpeter]

Awesome! I just ordered some on Amazon. It looks like this stuff is pretty common so I'm going to look for it in the stores now.

[@tasnimulsarwar9189]

@@dickJohnsonpeter kindly update if you can after you had some experience using it.

[@Dpix1990]

It's called SOS Silicone Tape here in Australia if anyone is looking for it.

[@dickJohnsonpeter]

@@tasnimulsarwar9189 will do.

[@tasnimulsarwar9189]

@@dickJohnsonpeter thank you good sir.

[@zenithproject817]

Holy shit the space welding is amazing

[@Warhawk76]

Love the Sir Patrick shrine, so appropriate to have one.

[@gabbylikeskicks]

0:40 legit checked if he was still alive after I saw that

[@AshrellStudios753]

So is he?

[@stan52323]

​@@AshrellStudios753 Google it

[@Kelvinkelvin666]

@@AshrellStudios753ya

[@conkerthesquirrel4331]

I'm an injection molding process engineer and this is one of the most interesting things I've ever seen on the internet. Making flow fronts "re-bond" after they go around a core or other feature in an injection mold is a very difficult. We look at is a minimizing the weld line as you can't make these polymer chains truly re form. Typically this is done with greater injection speeds or higher temperatures. Albeit, greater injection speeds induce shear, therfore.. also heat related. Very very cool video. Thanks Steve!

[@ItsWaltieTime]

This explains why I find so many plastic water valves that fail at the seems in the equipment I service. Mystery condensation appears in the cavity... follow the mist.... mind boggling micro hole allowing water to leak. You'd never see it with the water off, looks perfectly solid.

[@pumpkinpooper]

Uh..sir with that pfp ,sure we all beleive u really is an engineer molding process injection

[@lizard-breathOG]

@@pumpkinpooper not to say it doesn’t take intelligence to do what his job requires, but I ran plastic injection mold machines since I was like 12 in my dads shop. You have to understand what the buttons do, how to change the molds in and out, how to unclog it, and what to do when the plastic is shooting into the mold weirdly. Plus a few other things I’m sure I missed.. now granted, that is only one type of machine that’s usually in these shops, and if you have multiple of each type of machine, it’s usually from different companies so they all run differently. (These things cost around $150,000, from what my dads told me) I personally don’t know how to do all of these things, seeing as I only ran machines as a teen in the summers every year until I graduated. I never did most of the other stuff personally. but my older brothers and dad do. All it takes is working in a machine shop for a few years and having someone teach you everything through those years. It’s just like being a mechanic. You have to understand the machines you work on, and that they’re all similar but still have important differences. that doesn’t require a degree, it just requires on the job learning for years!

[@pumpkinpooper]

@@lizard-breathOG i do respect u for explaining this , dear lizard breath. btw u said it does not require a degree so basically what ur comment is implying is that the orginal person who posted the main comment is dump.. ? right if thats what u are implying , i am 100% agree with u that guy is probably dump{guy posted main comment} u sir are a chad giga cool chad

[@lizard-breathOG]

@@pumpkinpooper well, I’m not saying he’s dump😂 more so I mean, he probably has put in a lot of work over the years to learn all these things, but it’s not like you need a degree to do it. (So I don’t think he’s stupid, you just don’t have to be a genius) It’s just on the job learning for a long time. The machines are actually pretty complicated and some of them have like 40 buttons or touch screens. And you have to know how to download the info from the computer onto the machine, but I think that just takes knowing how to open files from a USB stick onto the machine. Also the molds in the plastic injection machines are anywhere from about $8,000 to like $200,000. It just depends on the size, how complicated it is, etc. so the fact that he’s the main engineer guy means he’s proved himself to the company with his knowledge and productivity! Also you have to be hella strong to move those things. One of my brothers lost a finger cause he wasn’t paying close enough attention when putting a mold in the machine 😂 I bet this guy is just your average machine mechanic/operator who has learned his specific trade well!

[@bioluminescence2391]

Floating a cruise ship with a gallons is easy as long as you have a external shell for the ship that is tight fitting , and makes a streamline thin layer of water that can’t be compacted any more and make it stretch along the whole ship

[@balazszsigmond826]

Edit: continued the video and you spoke of this... It is very much possible to "cold weld" metals, but only if the parts are completely flush and without any oxidation. Depending on the success of the cut, the material will be just as strong as if it was never cut in the first place. Dad went to a metalworking school and had his practice at a forge. He saw the process and even though cold welding is never perfect, I found the idea bonkers and fascinating.

[@Moofy]

2:35 YOU just BLEW my mind! 🤯

[@DrNEMO]

You got me with your little Patrick Stewart altar 😂 Beautifully explained and incredibly entertaining, as usual, Steve!

[@MrM6d]

But just a hedge bit creepy too.

[@user-ti5gy5py1y]

@@MrM6d You don't have little Patrick Stewart altar, do you?

[@MemekingJag]

@@user-ti5gy5py1y he doesn't have a little Patrick Stewart altar >.>

[@meekotheotter2801]

@@user-ti5gy5py1y imagine not having a Patrick Stewart altar haha, this guy must be really boring and weird

[@yakubyakub8849]

I love that you actually play devils advocate and answer any questions I had

[@EthanNeal]

2:45 if I remember right, it is possible to cold weld some metals even in the presence of oxygen. You just need two surfaces that are flat enough that don't oxidize and then squeeze all the air out from between the two pieces.

[@SianaGearz]

I've heard it said that you can cold weld gold on Earth but it takes something like centuries.

[@alexoja2918]

Some machined surfaces will stick to each other really strongly. Feels like a weld but it breakable.

[@talibong9518]

Like explosion welding, where 2 sheets of metal are forced together by explosives that squeeze out everything in-between them.

[@jeffs-reviews]

Take two blocks used to measure calipers, the smoother and more parallel the sides the better and they will stick to each other without any glue or "healing"

[@SianaGearz]

@@jeffs-reviews The blocks are very smooth and covered in a layer of grease. If you follow a procedure which pushes out the air, what you get is blocks held together essentially by vacuum, not too different from a suction cup on a tile. They will not weld together.

[@christatler7378]

In the electrical industry we use a tape called amalgamating tape. The tape is used for wrapping up joints made in cables that are outdoors like power lines. It is extremely stretchy and when applied it is stretched an wrapped around, and as it tries to shrink back it kind of bonds and the layers stick together similar to the polymer in the demo. I was always fascinated by this tape but couldn’t work out how it could work because it wasn’t sticky. What’s even more fascinating is why most materials don’t bond back together. Good demo and liked the shrine to PS.

[@LUMIX.]

Or by using the metal combining formula in vacuum, it's basically just that the polymer has a really low joining temperature that makes it join. Example Gallium.

[@gucciyae312]

"Life a knife that cuts you the wound heals But that scar, that scar remains" I feel like my comment is underrated

[@juliusc.2088]

Have you read into the following paper: 10.1038/s41578-020-0202-4 I belief there is more to it than the localized chemical reactions that you also mention (i.e. polymerisation). Aluminium, for example, can also have a variety of self-healing mechanisms, e.g. based on a reaction with oxygen. The product (Aluminium-Oxyde) is not permeable to O2 molecules, so it prevents further oxidisation after physical damage to the surface. For the polymer, it might be that the force from pushing the two pieces together is enough activation energy to initiate reactions. If that would be the case, maybe a thermal image would indicate an exo- or endothermal reaction. You could also change the topological structure of the stripes to see, if that impacts the self-healing mechanism. Maybe some adhesion effects are in place.

[@TROPtastic]

I'm no materials expert, but I believe the protective oxide layer in aluminum is a different type of self healing than whatever is going on here, since that only protects against further oxidization (unless the layer is damaged) but it doesn't allow two pieces of aluminum to be joined into one after separation.

[@beautifulsmall]

Applied science channel Google scientist Ben Kraznow , this could be one for him. Super in depth science of the wonders of nature.

[@ssnjr1299]

@i don't make memes put it back then

[@SteveMould]

Hi Julius, thanks for the insightful info, really appreciate it. If you're interested in joining my Discord where we chat through ideas here's a one time link: discord.gg/VzsRmy7A

[@humphreyjones1828]

The micro capsules sounds exactly like ancient Roman concrete. It contained bits that when exposed would kind of mend the break in the road

[@simplysierra9483]

It’s like when storing latex you gotta powder it so they don’t fuse. But at an expedited rate. Pretty much immediate. Amazing.

[@williamdrayer5166]

I suspect this is indeed a crosslinking reaction, and probably more specifically a tautomerization so that it can occur appreciably at room temperature (keto-enol is the simplest example for those unfamiliar, probably along similar lines due to the stability of the resonance structures especially with ketones but this is probably a more complex reaction). The (mild) pressure application probably pushes the equilibrium enough to significantly increase the crosslinking fraction. Probably also at play here is the viscosity dependence on pressure (and to a lesser extent, temperature). I agree it almost certainly is not self-healing capsules. playing with the pH of the polymer could also reveal the mechanism along similar lines to keto-enol structures requiring the proton in the pseudo-ring. source: polymer engineer PhD candidate

[@hitmanRazo]

I'll take your word for it lol

[@Defensive_Wounds]

Is this why even when he crushed it in his fist at 7:15 while trying to pull it apart, it still stuck to itself?

[@tonyguy9762]

Tautomerism requires strong reagents, typically something like sodium hydroxide (aqueous) would be able to produce conditions that would yield less than one percent resonance structure (enol) and this would only occur in polarising conditions. In the solid state molecular collisions are unlikely between the two surfaces in same way as if in the liquid phase. Also you would expect a product of a tautomerism reaction to have to leave the chemical system to drive such a reaction, for a stoichiometric reaction you would require reactivity to the order of say sodium hydride, and then it would have to evolve an equivalent of hydrogen. And the material is in its solid state, between the lower glass transition temperature and the melting point, so viscosity isn't relevant. I suppose ligation due to the molecular motion exhibited by elastomers in that range could be called solid state complex formation. ATB with the research.

[@williamdrayer5166]

@@tonyguy9762 my mention of viscosity dependence on pressure precisely points to the idea that the added pressure may induce more liquid-like behavior. I'm more confused that you mentioned this is lower than the glass transition but also call it solid state: I particularly study polymer glasses (or supercooled liquids, if you prefer) and particularly object to calling a glass a solid. There is no distinction between the molecular behavior of a liquid and a glass, so the collision behavior should be indistinguishable. Viscosity is absolutely relevant: glasses only appear "solid" to us because of the mismatch of viscosity (or relaxation time) and the observation time window (for us humans, on the order of tens or hundreds of seconds). I certainly do not deal with chemistry much, so I have no guess as to that. But this is clearly an amorphous crosslinked polymer, that appears to form crosslinks when pressed together.

[@williamdrayer5166]

@@Defensive_Wounds yes this was part of my thinking

[@diarya5573]

One of my biggest aversions to material sciences was trade secrets. It's such a stupid thing getting in the way of faster growth, I tended towards things that, you know, can't be patented

[@mattheffron391]

In terms of propagation of the information and growth of the knowledge, patents are nearly as good as "freely available". Neither keep the information secret. Trade secrets are, by definition, secret. However, if discovered independently and disclosed, the trade secret has no value per se.

[@kjdude8765]

@@kirayoshikage4057 I tried reading this with an open mind but I couldn't figure out any way to read this and it not be totally racist.

[@diarya5573]

@@kirayoshikage4057 Mmm yeah the rich white elites definitely don't play their part in screwing everyone else in the world eh

[@TomFoolery9001]

@@kjdude8765 Yep, anyone who really believes what he believes is just out of touch with reality. Greed is very independent of any religion and tying it to one religion is just crazy and stupid.

[@RoflcopterLamo]

@@kjdude8765 what he say?

[@archonwarrior9146]

As a polymer chemist (in master studies) myself i am pretty amazed by this. There are multiple theoretical ways for self healing polymers, but due to the fact that you can literally fold this one together and don't require it to be damaged, the most likely theory is: Highliy functional side chains, that allow for strong interactions (probably VdW-forces) without binding as this would make the polymer itself VERY rigid and it probably would be unable to bend like that

[@budzillasohoski9858]

I literally sit down on the edge of my bed for like 20 minutes after I do laundry and try to figure out where the hell that one missing sock went…I’m 50…still no answer. You’re splitting atoms and polymer chains. You are a smart cookie.

[@mattheffron391]

Similar to cold welding, I recall seeing a discussion in a Caltech publication that cleaving a diamond in a vacuum would leave 2 surfaces that could be brought back together and rejoin. IN THEORY, if the surfaces were perfectly realigned, then the diamond would have no optical defects evidencing the cleave and rejoin.

[@alexlutz2221]

@@MonkeyJedi99 Gage blocks aren't wrung together causing the same type of thing as the tape though. I believe it's due to them being such a tight match that wringing them pushes most of the air out of the gap creating a slight vacuum. Not completely sure on that but I do know that it's not magnetism as I believe ceramic gage blocks will do the same thing and it's not cold welding as the joint isn't strong enough for that and there is a very very small oxide layer formed almost immediately when metal is machined and these blocks sit in a box specific gage blocks potentially not being used for years and then will still wring together.

[@MonkeyJedi99]

@@alexlutz2221 I did not even hint at magnetism, and I think you are right that the precision surfaces "wring" because of vacuum.

[@jsmith5443]

Cool

[@JamieBainbridge]

Excellent Patrick Stewart shrine, happy Captain Picard Day!

[@idontreadorreply]

Thank you, this feeds my never-ending hunger of learning something new :)

[@tantilist1449]

In the navy we have this exact thing. We call it "Cherry Tape" it is used to wrap around electronic connectors .

[@patmat.]

Awesome perspective, as a mechanical engineer I understood that glueing happened mostly at the molecular level but I never thought about it for metal or plastic cutting.

[@RealValkor]

Not gonna lie, I got mindblown to know about metal being able to glue back togheter once there is no oxygen.

[@tenorHarlequin]

This man literally answered every question that popped into my mind as they popped up.

[@SyeedAli]

I'll guess: When you apply force, that "splays" the material on a molecular level, something like how velcro works, such that if the material is pressed against the material, the two splayed surfaces will open up to one another then un-splay and close to reform a contiguous surface. Try stretching two separate pieces on top of one another, and testing what amount of pressing-force is necessary to fuse them. Try quick pulls and show pulls, etc.

[@Kay-Renee]

I love the way you explain like it's all common knowledge... Like obviously plastic wouldn't stick to itself because you just broke the perimeter of the mitochondria

[@lincolnsghost7328]

This thing about the cold welding of metal in a vacuum is something I’ve never seen or heard represented in science fiction.

[@danielweller1291]

Hey Steve! Big time fan. Great explanation of a very cool material. I've studied polymers for many years and a common mechanism for self healing polymers is using monomers that bond to one another through an array of hydrogen bonds (typically 4-6) rather than a single carbon-carbon covalent bond. Because hydrogen bonding relies on secondary forces they can be broken and reformed repeatedly. There's other strategies too but I always thought this was a fun one! Loved the video

[@wiez543]

This is what I learned in Uni, too.

[@SteveMould]

Hi Daniel, thanks for the insightful info, really appreciate it. If you're interested in joining my Discord where we chat through ideas here's a one time link: discord.gg/UemmPhW6

[@Unherd_Of]

How did I go from emotional work to fully engrossed in this fusion video. Thank you 😊

[@BlackPantherClimbing]

I have this material as a screen protector on my phone. It was said to be what NASA use to protect the windows on spacecraft from small debris. Yes; it really does heal its self. I have had it for years, I've had nasty gashes taken out of it, and it returns to normal in time.

[@richardmcdaniel4467]

Tape that only sticks to itself? Sounds like every time I’ve ever used any kind of tape!

[@StevePittinger]

I just discovered this channel a few days ago, but it didn't take long to notice and appreciate the recurring appearance of Patrick Stewart. His appearance in the various contexts is, quite plainly, comedy gold. Thank you for mixing scientific learning with light hearted humor, it makes learning of new concepts that much more enjoyable.

[@joekrater3364]

hmm... gold cold welds

[@st_kek_oparis]

I really enjoy watching such cool videos.

[@Hinotefrom183rd]

I would love to learn about how our skin cells work in this format of explanation. We’re also self-healing as well, just not like polymer-based formats. I skateboard, so it’ll be very convenient to understand how self-healing truly works on all forms of life itself. Thanks for the info! You got a new subscriber from me! 🎉

[@amasterofone]

In case you're still wondering, that has to do with cells ability to replicate and bridge the gap of an open wound. Collagen forms the lattice that this happens on. People with collagen disorders can have very stretchy scar tissue which leads to very thin wide scars.

[@blazernitrox6329]

If I understand correctly, something similar to the micro-encapsulation theory is exactly what happens in bird meat. It turns out you can literally pound a chicken breast into a flat sheet and it will remain as one solid piece of chicken, whereas doing the same with a steak will just cause it to shred. Apparently bird muscles get torn so often during flight that they evolved a special chemical for fusing the proteins back together, but only inside of a short timeframe. Cooking the meat decomposes the protein and the chemical itself, which is why you don't end up with chicken amalgam in your gut after you eat some General Tso's.

[@MeltedMask]

Interesting, must be related to 'meat glue'. Btw, main function of stomach is to denaturate organic chems and decompose proteins to aminoacids. So there is zero change it to bind with gut, even if you eat raw meat.

[@gregbits6109]

When the question’s first reversed I just assumed it was to lengthen the video, but I’ve actually never thought about what makes things NOT stick together…

[@MegaMuffinManX]

The one type of self-healing polymer that I'm really curious about is the type used in blood collection tubes. Most blood collection tubes have a rubber(?) cap at the top. To fill the tube, you pierce the cap with a needle. But when you take the needle out, it doesn't leave a hole! (Which is great, because you typically need to invert the tube after you draw blood and you don't want a contamination risk of any blood leaking out).

[@roush876]

I use insulin vials and wondered the same thing sometimes.

[@jonas36699]

I really dont think this is some kind of self healing polymer. Probably just rubber, as you said. You make a hole, but you cant see because the walls get pushed in. This also seals it.

[@dangolfishin]

Thats just elastic

[@thisreckless]

This is the same for micro mushroom grow bags. The injection port reseals but not in the sense you think. It just expands and the port closes up.

[@turfdesturcto7325]

Learnt more from this than I did in science class this year

[@ejoojoo]

hoping for a self healing 3D printing filament, it will eliminates layer separation and possibly making it non porous.

[@armadillito]

Now that could be amazing

[@ADBBuild]

How would you keep it from bonding when on the spool though? Perhaps some kind of coating that burns or melts off when extruded?

[@bluejayechaosenbybirb5865]

@@ADBBuild It might just be me, but when I think of coatings meant to be burned or melted off, I can only think of things that would either give off harmful fumes, making it impractical and unsafe to use indoors, or make a mess, potentially also mixing in with the filament as it melts. It may not be the most practical, but I feel some sort of removable thin paper shell similar to a straw wrapper could be a decent solution. Considering existing technology, a system to automatically remove and collect the paper as the plastic is printed seems fairly straightforward to design. There's also the added bonus of paper being recyclable; if the system of collecting the shell is efficient enough, they could even be directly used for multiple spools Well, if this sort of self healing material is even suitable to print with. It seems rather flexible, making it impractical to print anything intended to hold its shape Now, it's very likely that I don't actually know much about 3D printing or anything I'm talking about (after all, it's hard to know what information you don't have), but these are just my thoughts with the limited knowledge I have Wow this is a lot more words than I intended to type when replying to this comment

[@fuzzydane2090]

I think you might have an easier time post-processing existing filaments - it's possible to create gastight, food-safe prints on regular, consumer-grade fdm printers. Unfortunately I've signed an NDA, so I can't quite disclose how it's done :-/

[@SianaGearz]

@@ADBBuild You could have a carrier on the spool made out of... corrugated cardboard open on one side? Separating the layers of the plastic. You would have like a dozen or two loops side to side in their own wells, and once they're all unspooled, the cardboard protector piece simply falls down from the spool and the next layer becomes usable, and there'd be these between each layer. Honestly i haven't thought this through, i really don't know whether this would work. But it's a direction to explore, potentially, if the whole self healing filament idea has any legs to stand on - i really doubt. Another possibility is to rely on the mixing action of the nozzle, though unfortunately it's pretty weak, but maybe with CHT nozzle or an insert similar to those used in injection moulding, it could be improved. The filament could be coated with a barrier polymer that doesn't have the self healing property and prevents the filament from healing onto itself, but as it gets mixed in, during extrusion, the self-healing polymer gets exposed on the surface of the extruded bead. The fact that a very thin barrier layer would be sufficient is on your side, the barrier material could be barely a percent or less by volume and might not end up influencing the properties too much.

[@volundrfrey896]

There is this "self vulcanizing" (not sure if they're called that in english) rubber strips you can buy that does this too. They're been around for ages. Really cool stuff, I think it used to be popular for handles of different kinds before single piece stuff became cheap.

[@fauzirahman3285]

Is there a chance that this might stick with other materials that just have a similar kind of chains that it can link to? Also what's to stop it from eventually rolling up into a ball?

[@TesserId]

Loved that close up of the cut sodium. Never seen it depicted quite that way before. You could see the surface seem to bubble. What is that? Is that oxidation straight from the air? Or, could it relate to sodium pulling water out of the air? I'm tempted to say: "call in the slo mo guys", but what we may need is super macro guys who have the tech magic to overcome the sharpness robbing depth-of-field problems.

[@MrDowntemp0]

I want to hear more about how a tire is just one giant molecule please

[@kjdude8765]

Read up on Vulcanization of rubber. Basically sulfur is used to crosslink all the rubber molecules into a single durable one.

[@fluffypink90]

Look up "vulcanisation" for the process of cross-linking rubber as is done with tyres.

[@danielvalle3789]

I nearly fell off my chair over the Patrick Stewart shrine bit!!! Hysterical cuz it catches u off guard! Lol

[@WilliamWizer]

I'm sure it's not the same but it kind of reminds me of bondage tape. it sticks to itself but not to other materials.

[@Meta-Drew]

ahaha I love your Patrick Stewart shrine, I didn't know I needed that laugh

[@NicosLeben]

2:30 But you should be able to fuse gold together because it's noble.

[@meliviktoria]

I love science questions and explanations that u don’t think about everyday and now one feels like they gained a neuron ❤️✨ glad u popped on my feed, you have my subscription Steve

[@JackClayton123]

They use ultra high molecular weight polyethylene to cushion inside artificial joints. Awhile ago, they increased the strength of this polymer by gamma irradiation. The increased cross linkage significantly extended the life of these implants.

[@davidvalenzuela3144]

Piezoelectric quarts crystal powder in polymer mixture. The contact between both crystals causes enough energy to cause a bond in links.

[@iSmartMan1]

0:50 Controversial question: is water sticky?

[@Blobfishlovr69]

No it's wet

[@YeetBoi678]

Except the white variant

[@firewhite]

@@Blobfishlovr69 it’s not wet

[@dangerparade2913]

@@firewhite of course it is

[@firewhite]

@@dangerparade2913 tell me, is fire burnt? i don’t think so, so why would water be wet

[@faucamargo]

You blew my mind! Im a materials engineer and never really gave thoughts about this... amazing content!

[@tylerplayzzrecroom]

Deadpool: "Oh, great, now they're trying to make another version of me! Does that copyright symbol even work?"

[@roberts3423]

A self healing phone screen or any device, car windshield, windows, would be interesting. I know something similiar to this polymer is used with medical bandages, it sticks togheter quite well.

[@Brine101]

I first saw that stuff about 10 years ago, i mainly used it for fixing holes in air mattress tubes for nursing homes. I found it facinating it would stick to itself but not to anything else. and would create an instant airtight/water tight seal.