all right hi youtube this is mr lim here again this is our video on polyamines all right so we're going to be learning about polyamines duh all right so polyamines it's a condensation polymerization again all right making a small product a small molecule as a byproduct of water this time we're combining a carboxylic acid with an amine right which means that we're uh and then they're going to form an amide group as the uh as the link between the two monomers okay so it's an amide group so it's going to look like this c o o n and then a h okay and that's going to be the link between the two substances okay um so polyamides can be formed from a dicarboxylic acid and a diamine okay and the backbone chains of all the atoms between the two carboxylic acid groups and between the two amine groups so let's try this one here one for butane di amine okay so butandi amine so here is one amine group here is the other amine group and we've got a whole bunch of hydrogens there and then what's the other one ethan dioicic acid off that's nice and easy uh ethan dioic acid also known as oxalic acid okay so there are my two functional groups also very my two monomers as we said before we're going to combine the carboxylic acid part will take away that part and one of those hydrogens and they're going to form a water okay and then you're going to be left with an nh here in h with a c o oop not with that o with a c o there okay that o here that one there goes to the h2o so that's why that's there's no o between those ones there so let's try and drop this one out okay um so let's draw this out all the carbons between the amine groups how many are there there's four of them so four carbons between the amine groups then it goes to an n and a h and it goes to the carbon which is part of the other one there but also with a double bonded o okay to another carbon with another double bonded o with another n with another h with another bond to the four c's with another bond to an n with another bond to a h with another which now we're going back to that c and that o there and we can continue on okay and now you notice that i'm drawing this n in green but really it can be in red as well because it's coming from the red monomer okay remember you leave these open ended right so that's two repeating units there okay um so you can see that the uh the amide group that's formed is well bidirectional which means that like you know there's one going that way one going that way right one going that way and then one going that way okay which means that we can tell that it's from a two a diatomic silica acid and a die amine all right um so that's on that one there okay so let's try uh what have we got one three cyclohexane diamine and methane methylpropandioic acid okay so let's draw a cyclohexane uh cyclohexane and a one three so this one we'll call it the number one and then it's gonna be two in this corner um two in that corner and then three in this corner so that's where the number three will go okay and then methylpropandioic acid so propane dioic acid propandioic acid and then it's got a methyl group and it can only be on that one there okay so that one that's that one there so let's put these two together okay so here i have my hexagon okay i'm gonna have an n here connected to a h okay draw a proper bond there okay and then an n here connected to a h which is connected to c from the protein dioic acid the methylprep and dioic acid okay so it's going to have the cc and then the extra methyl group there this carbon is going to have a double bond to another n to another h and then this is where it goes to another hexagon and then where is it going to come out up here another n h and then you can bond it to another c c with a double bonded o with more carbons here and then another double bonded o and another n with another h going to another uh going to another hexagon all right remember to make these open ended put brackets around it how many repeating units have i drawn two repeating units okay and then when you do draw these out in tests don't forget to draw out all the um all of the wasabi's the hydrogen atoms okay so let's move on uh polyamides can also be formed from a monomer with one carboxylic acid group and one and an amine group so again an amino acid just like the uh polyesters can be formed from a alcohol and a carboxylic acid on the same molecule so the backbone of the chain is all the atoms between the alcohol oh yep i haven't just copied and pasted this from the other slide from between the amine and the carboxylic acid functional groups okay so let's try this two amino pentanoic acid okay so pentanoic acid two amine so two is here that's a stupid place to put the amine group i'm changing that that doesn't say 2 that says 4. otherwise it just looks like the last one we did because you know mr lim never just reproduces stuff fat that would tear it be terrible all right here's all your extra hydrogens how many carbons have i got in between the amar amine group and the carbon i've got four effectively so those are going to be making up the four of the backbone okay so let's draw this out so one two three four there's going to be a a double bonded there and n h here and then another four and then a double bond here at the end here and there okay and let's just call that the ends okay remember i've got to put in this part here which is not on the which is not in part of the backbone it's going to be a side group or side chain of some sort all right so where will that go that will have to go on the carbon that is also attached to the the nitrogen so that one is going to have to go on that one there and if you if you think about it there's going to be a nitrogen over here as well and so therefore that's going to that's going to be over here as well okay so you're just going to be able to see it uh as the one on the end the one that's not part of the backbone because it's not in between the carboxylic acid and the amine right don't forget all your other atoms they're honest i never forget them all right and then you'll be able to put them together okay um you have a go at doing a four amino benzoic acid just if you can't if you don't know what a benzoic acid looks like here is your carboxylic acid group because you have to have the carboxylic acid coming off the benzene ring and then since it's on the four it has to be if this is one that's two that's three that's four so therefore the amine is on the four which is over here so that's the n and the h2 okay so you draw that one out and see what that looks like okay and that's it adios