Making nylon

this video is sponsored by audible nylon is an extremely important family of polymers that can be used to make a huge range of different products it can be strung into fibers to make things like clothing and textiles or mould it into plastic parts and tools nylon was first used to make the bristles for toothbrushes and it's still being used today it's also used to make women's stockings which have become known as just nylons there are many forms of nylon but the most common ones are nylon 6 and nylon 6-6 each type of nylon gets its name from the length of its building blocks for example nylon 6-6 is made from two ingredients where each one has six carbons nylon six on the other hand is made from just one six carbon chemical there are other forms of nylon like nylon four six or nylon six ten but they're not as common the different lengths of the building blocks gives the final polymer different properties which makes them useful for different things for example nylon 610 is better at retaining its properties when wet so it's the nylon of choice to make things like toothbrush bristles anyway I decided to make nylon 6-6 and there's two major ways to do this industrially adipic acid is first combined with hexa methylene diamine to form a nylon salt the nylon salt is then heated processed and extruded as nylon 6-6 the other way is to first convert adipic acid to a de poil chloride and then reacted with hexa methylene diamine for this video I've decided to go with the second method because it has a much prettier demonstration however I do plan to cover the industrial one sometime in the future okay so to start things off I need to convert the adipic acid to a defile chloride and to do this I'll be using four main chemicals DCM DMF adipic acid and exile chloride the adipic acid was made in a previous video and I'll have a link in the description if you want to check it out instead of eggs a little chloride it's possible to use other chlorinating agents like thionyl chloride but they're a lot harder to get a lot of them are listed as precursors under the Chemical Weapons Act so they're not exactly the best thing to own the adipic acid isn't super pure so before getting started I decided to clean it up a little I dumped it all into a beaker and then I added a whole bunch of distilled water although adipic acid isn't very soluble in water we still don't want to add too much here before continuing I quickly check the pH which came out to be around three which is expected for a dybbuk acid I made a solution of about 6 molar sodium hydroxide and I started to add it slowly the sodium hydroxide is a strong base and it will quickly react with the adipic acid to form sodium adipate and water unlike adipic acid sodium adipate is very soluble in water so as we continue to add the sodium hydroxide the solution should clear up I know I'm done adding sodium hydroxide when I get a pH of around 7 all of the adipic acid should be in the form of sodium a debate and the cloudiness here is due to impurities the impurities that are present seem to be very small particles which tend to easily pass through filter paper so to get rid of them I have to instead filter it through something called sea light which is very similar to extremely fine sand the solution passes through relatively slowly but the stuff that I collect is crystal clear once everything is being filtered I wash the beaker and the funnel with a little bit of distilled water I again wait for all of this to pass through then I take away the funnel and I drop in a stir bar so now that I've cleaned things up a little bit it's time to regenerate the adipic acid to do this I add 6 molar hydrochloric acid until I get to a pH of around 1 the hydrochloric acid reacts with sodium adipate to make a dip academy implore ID is very soluble in water but the adipic acid isn't so it precipitates out I continue adding the hydrochloric acid until I get to a pH of about 1 the beaker is placed in a freezer and cooled to around 5 C and then the adipic acid is filtered off the beakers washed a few times with a small amount of distilled water once everything was pulled through I turned off the vacuum and did one final and thorough washing I turned the vacuum back on and I left it running for about 20 minutes to try to dry it up as much as possible I scraped the adipic acid out of the filter and I let it dry for two days when I came back it was a relatively dry powder and I transferred it back to the original container okay so now we're ready to do the actual reaction and I start by dropping in a magnetic stir bar I then add 5 grams of adipic acid followed by 70 milliliters of dichloromethane and the last ingredient is a small amount of dimethyl formamide which will be acting as a catalyst I took away the funnel and I replace it with a vacuum adapter above the adapter I attached a small addition funnel and I added 11.6 milliliters of Uggs a low chloride oxalic chloride is a very dangerous and corrosive liquid and you can see it fuming it's a very strong chlorinating agent and I do my best to avoid working with it to the vacuum adapter I attach some tubing which leads outside this reaction produces a lot of hydrochloric acid gas as well as carbon monoxide so this definitely cannot be done in a closed space my work space is extremely well ventilated and I just added this tubing as an extra precaution when I was ready to get things started I turned on the magnetic stirring most of the adipic acid is not going to dissolve and this is perfectly fine I open the addition funnel and the example chloride is added over the course of about five minutes my dichloromethane and adipic acid aren't perfectly dry so there's a little bit of water present the first little bit of exalted chloride that's added is going to react with the water and it can sometimes be pre vigorous it's highly unlikely that it would ever cause it to bubble out of the flask but it's just a good precaution to take anyway so as I said the initial reaction is just with water which produces hydrochloric acid gas carbon monoxide and carbon dioxide once it reacts with most of the water and gets rid of it it will start to do what we actually want it to do which is react with the adipic acid when it does it will convert the carboxylic acid groups to acyl chlorides and lead to the formation of a de poele chloride it will also produce carbon dioxide carbon monoxide and hydrochloric acid gas as side products this is why it's really important to have good ventilation because you really don't want to be breathing in hydrochloric acid or carbon monoxide because exile' chloride reacts with water and I want to make sure that all of the adipic acid is consumed I need to use an excess of it I used about twice the amount that was required which assures that the reaction will go to completion but it also means that example chloride will be left over at the end I'm now just going to quickly go over the mechanism in the first step the electrons on the nitrogen of DMF move to form a double bond the other double bond opens up and the electrons go to the oxygen the free electrons of the oxygen then attacked the carbonyl of eggs aloe chloride and open up the double bond the electrons on the oxygen then moved to reform the carbonyl and the chloride is kicked off the free chloride then swings back around and attacks the double bond this leads to a cascade of electrons jumping around and the formation of the active villes Meyer reagent the carbon bonds in the exalted chloride are broken apart and it leads to the formation of carbon monoxide carbon dioxide and another chloride ion the chloride then attacks adipic acid and pulls off an acidic hydrogen the electron shift and the carbonyl is opened up the free electrons on the oxygen then attacked the bills Meyer reagent and kick off a chloride the chloride ion that's kicked off will then attack the carbonyl a carbon oxygen bond is broken which regenerates our DMF catalyst and forms the final acid chloride product the reaction is then repeated to the other side of a diptych acid after the last bit of exile chloride was added it took about three hours for the adipic acid to completely disappear during this period the bubbling slowed down a lot and the solution slowly became more and more yellow a deploy L chloride is slightly yellow so this color change is a good sign eventually all of the adipic acid was consumed and there was no visible bubbling from this point the solution was stirred for another 24 hours 24 hours later the solution is significantly more yellow it's also a Paik due to impurities which will need to be filtered off to do this I filter it through some see light and glass wall before filtering through the actual solution I wet the C light and the glass wool was a little bit of DCM it's important to use glass wool and not just regular cotton because the example chloride and the atom oil chloride would probably destroy it I tossed away the solvent that passed through and then I started filtering the real thing one thing to be aware of is that a deployed chloride is sensitive to water so it will react with moisture in the air in theory it's best to do this in a water free environment but I don't have one so I try to just filter it as fast as I could one thing that's helpful is that we have excess eggs a low chloride leftover eggs a lil chloride is much more reactive so in theory it should be able to pick up the water and protect the atom oil chloride once everything had passed through a small amount of dichloromethane was used to wash the round bottom as well as the funnel when this was done I took away the funnel and I dropped in a stir bar okay now I need to get rid of all of the dichloromethane as well as any unreactive eggs a la chloride and to do this I set up a simple vacuum distillation I set up a hot water bath and with strong stirring I slowly turn on the vacuum it's really important to engage the vacuum slowly otherwise it could bubble out of control I continue with the distillation and unfortunately at some point it becomes opaque again this isn't a huge deal but it does mean that I have to do another filtration anyway I keep going until it completely stops bubbling and I'm left with this dark orange residue in a previous run that I did it didn't turn orange and I just had a yellow liquid I'm not exactly sure why there was such a difference here in either case though I had a mixture of a deployed chloride and a bunch of solid impurity unfortunately most of the impurity comes from the dirty adipic acid that I started with if I started with very pure adipic acid I probably would have had relatively clean out of oil chloride at this point anyway it is what it is and I now need to separate my atom oil chloride from the other solid junk to do this I start by adding 50 grams of dry cyclohexane the cyclohexane will dissolve the auto coil chloride but it won't dissolve the other stuff after its added I put the stopper back in and I stir it for about 10 minutes to filter it off I do the exact same thing as before where I pass it through see light and glass wall before I pour it in I wet things with about 2 grams of cyclohexane anyway the cyclohexane solution is added to the funnel and it slowly starts to filter through at this point we can see that the solution itself is yellow and the orange color is coming from the solid stuff I added as much as I could without including the solids to try to get it to filter through as fast as possible once almost everything had filtered through I pour it in the last bit that remained the flask in the funnel was then washed twice first with 10 grams of cyclohexane and then with 16 grams in total I use 78 grams of cyclohexane which is almost exactly a hundred milliliters I wait for everything to pass through when it stops dripping I take away the funnels and I cap the bottle what I have now is roughly 0.2 molar out of oil chloride solution which will be used directly to make the nylon the solution is a little bit opaque because some of the outer pol chloride reacted with water in the air and precipitated a dybbuk acid to make the nylon I need to make a solution of hexamethylenediamine when I open the bottle and take a look inside it's completely solidified and it has formed some very nice crystals with a lot of difficulty I scraped out 4.4 grams and added it to a beaker hexamethylenediamine is quite corrosive so it's important to wear gloves and be careful when handling it I added 50 milliliters of distilled water and I stirred it until everything dissolved some of the flakes floated to the top and started to zoom around which I thought was pretty interesting anyway once almost everything had dissolved I topped it off to about a hundred milliliters with the heads of methylene diamine solution prepared I'm ready to make the nylon the a deploy chloride seems to have gotten a little bit cloudier but that's not really an issue to make the nylon it's pretty simple I first add a little bit of hexamethylenediamine solution and on top of this I carefully add an equal amount of a deploy L chloride the add a polo chloride is dissolved in cyclohexanol which doesn't mix with water and it's less dense so it floats on top because they're not mixed the only place that polymerization can take place is at the interface between the two solvents using a pair of tweezers I can pinch the nylon and pull it out of the beaker the gooey string is wrapped around a glass stir rod which I can then turn to pull out more nylon what's interesting here is that the nylon I'm pulling out is not actually a string it's more like a tube the tube isn't hollow though and it's often filled with hexamethylenediamine solution so it's important to be careful when handling it so now to talk a little bit about what's going on here when the a de poele chloride comes in contact with the hexa methylene diamine it reacts to form an amide bond however on one end of this newly formed molecule we have an acyl chloride and on the other we still have a free amine so now the reaction can repeat itself and it keeps doing this over and over to form a very large molecule known as a polymer it looks like there's a whole bunch of nylon here but it's a little bit deceiving because it's being puffed up a lot by the water that's being pulled up with it it eventually runs out of either the hexamethylenediamine or the atom oil chloride when I squish it with my fingers you can see that there's a lot of liquid with the nylon to try to clean it I dump it all into a water bath without destroying the nylon I manually pull it apart to try to give it a better washing after about 30 seconds I just leave it there to soak and I move on to making more nylon I tried it again using the same amount of each ingredient but this time in a much larger beaker it ended up being pretty much the same thing and the only difference was that it was a little bit faster there's a larger surface area between the two layers so we pull more nylon with each turn it was a little bit tedious doing all this turning so I tried to make things a little bit more automated a glass stir rod was taped to an electric drill so this time I just need to click a button to pull out the nylon for this run I decided to see what would happen if I just mix the two layers together instead of pulling the nylon out as I continue to stir it slowly forms the nylon and turns into a somewhat disgusting mess after about a minute of stirring I'm left with an alien like blob stuck to the end when we take a closer look we can see a whole bunch of air as well as liquid trapped inside I then attempted to get creative by adding some flora scene to the hexamethylenediamine flora scene is a highly fluorescent molecule especially under UV light I actually made it in a previous video and if you're interested in checking that out there's a link in the description I turn off the lights and I turn on my UV light and then I carefully add the add apoyo chloride just like before I use the tweezers to pull out some nylon what's kind of cool is that we can tell how much water we're pulling up with the nylon based on how bright it flores's at some point I accidentally got the nylon stuck to the side of the beaker at first it was a mistake but it ended up being pretty interesting in hindsight I wish I put down the glass rod and using my fingers I probably could have pulled off a super thin sheet of nylon in another run I just poured in the Attic oil chloride and then did absolutely nothing I left it for about an hour and I wanted to see what would happen if I just let it react passively when I came back the a deploy L chloride layer was no longer yellow I poked around with a Gloucester rod and tried to pull some nylon using tweezers but it appeared that everything had reacted what's interesting is the same amount of nylon has formed here as all of the other runs in the other runs when I pull it out using tweezers it's an extremely thin layer and it makes it look like I'm pulling out a whole bunch of nylon however in reality there's actually only a very small amount Tron I used a lot more of each and I thought it would take a while so I used the drill as well near the end it got super messy and was pretty gross looking you I ended up having to transfer the huge messy blob and restart with a fresh glass rod the nylon from all of the runs was combined in the same Bowl and given a thorough washing mixed with the nylon is a lot of unreacted at apoyo chloride hexa methylene diamine and also the flora scene that i added in after a thorough washing and having to change the water several times I'm left with relatively clean looking nylon I personally didn't do it but to clean things further it might be an idea to do a dilute acid and a dilute base wash anyway the nylon was taken out and squeezed tightly to get rid of as much water as possible I then spread it out on some paper towel and let it dry for a couple days when I came back I had some nice and dry nylon with a mass of about 0.75 grams it was a little bit tough but still quite easy to break apart using my fingers all of the nylon pieces were then shoved into a small test tube I started blasting it with a heat gun and the goal now is to completely melt it the melting point of nylon is around 265 C so this is going to take a lot of effort it's also possible to use a Bunsen burner or a blowtorch but I really didn't want to burn things I occasionally had to stop and shove everything down to the bottom using a metal spatula once I got to the last little bit I continued heating it until it completely liquefied you'll notice here that there's some bubbling going on and these are impurities that are boiling off the major impurity is hexa methylene diamine which boils around 205 see the boiling eventually dies down a lot and I decided that I was pretty much done I allowed it to cool and to get out the nylon I smashed the test tube which kind of exploded I found the end piece that flew away and this is the nylon that I got despite the fact that it was low quality and dirty I was honestly impressed with it the portion that was in contact with the test tube was very shiny and smooth but the inside was a little bit bubbled up after seeing what I made here I decided that I would for sure make nylon the other way the other way is a lot cleaner and I should be able to get a much higher quality nylon out of it a big thanks goes out to audible for sponsoring this video and supporting my channel audible offers an unmatched array of content including audio books original audio shows news comedy and much more they're offering a one month free trial to all of my viewers which you can get by going to audible.com for word / nyle read it takes me a really long time to edit all my videos and to keep me motivated I usually listen to podcasts or audiobooks I just finished listening to the power of habit by Charles Duhigg and I definitely recommend checking it out it's a very entertaining and informative look into how habit influences our lives and what we can do to change it if that kind of book isn't your thing though there's loads of other books you can listen to like Game of Thrones or even chemistry textbooks so if you want to help out my channel you can sign up for your free trial at audible.com forward slash nyle read and claim your free audiobook so as usual I'd like to thank everyone who's supporting me on patreon everyone who supports me will see my videos 24 hours before I release them to YouTube on top of this all of my supporters can directly message me on patreon with any questions or comments that they have and I do my best to respond within about a day or so to all of my patreon messages if you support me with five dollars or more you'll get your name at the end of the video like you see here you

Channel: NileRed

Views: 2,647,414

Rating: 4.9085145 out of 5

Keywords: nylon, prep, adipic, acid, nile, red, chemistry, hexamethylenediamine, polymer, demonstration, fluorescein, educational, nilered, science, plastic

Id: HTh_5CWMSoQ

Length: 25min 48sec (1548 seconds)

Published: Sat Apr 22 2017