19:31 "So when you are talking to somebody who has faced a lot of adversity and overcome a lot of challenges, and someone calls them 'That's a stong person', you said 'No. That's a TOUGH person.'" Love it.
@djlipomi
11 ай бұрын
:)
@abdelmounaimsiffour3783
4 жыл бұрын
people like you makes students love science thanks sir
@djlipomi
4 жыл бұрын
Thanks!!
@ri3oz
7 жыл бұрын
I wish my teacher explained as clearly. Good work man!
@smitashivraj1793
4 жыл бұрын
Hello Dr. Darren Lipomi. I really enjoy all of your videos. I was always interested in polymers and material science. Thank you for all the helpful videos! Regards Smita
@djlipomi
4 жыл бұрын
Thanks!
@parimisreekar
2 жыл бұрын
Awesome lecture… was struggling with leathery vs rubbery vs rubbery flow comparison. Those graphs on right side and explanations really demystified it. Thank you Liporni.
@RidheshChachapara
6 жыл бұрын
one of the great lectures i have ever attended.....
@djlipomi
6 жыл бұрын
Thanks!
@enescaglarkorkmazgoz7897
3 жыл бұрын
STUNNING! Thanks for the content; I am glad to see something real before the midterm exam
@MrClaycorn
7 ай бұрын
Thank you from the UK bruv
@djlipomi
7 ай бұрын
Glad it was helpful!
@asyuki193
2 жыл бұрын
Thank you, this lecture was so precise and clean.
@duylinhpham4139
5 жыл бұрын
Great explanation. can't wait for your talk in emts2018 Hanoi.
@djlipomi
5 жыл бұрын
Thanks!
@matthieumanghardt4362
6 жыл бұрын
I think your student was right. If the response of the top spring was instantaneous when you applied the force (leading to a vertical line on the graph) then you should have an instantaneous response when the force is removed. The length of the vertical line after the force is removed should be equal to the length of the first vertical line. There is also no reason why the final strain should be equal to the elastic strain (the strain at the top of the first vertical line). It could be higher or lower. Apart from this your explanations were remarkably clear, thanks!
@djlipomi
6 жыл бұрын
Thanks for the kind words. I should have been more consistent in the response and recovery phases. The responses are never truly instantaneous, since all of the components are acting at the same time. You're right that the final strain does not necessarily equal the initial strain, since the Maxwell dashpot will never recover. The Voigt-Kelvin dashpot will recover fully, however. This is called the Burgers 4-element model. A more accurate drawing is here: pocketdentistry.com/4-rheology/#f0060
@JAlanne
6 жыл бұрын
thank you. This really helps me understand it much better.
@stochioiuconstantin546
5 жыл бұрын
Good day, Really comprehensive explanation. I would like to comment on the last model, as I agree with the student on the elastic deformation . It should be equal in amplitude with the deformation on the beginning of the load.
@djlipomi
5 жыл бұрын
Thanks. See my comment on this issue in the description.
@rufigeisa18
4 жыл бұрын
Thank so much !! Now, I actually understand :)
@djlipomi
4 жыл бұрын
Thanks!
@ainunzulfikar
6 жыл бұрын
thank you prof. Lipomi
@user-ex1yd3mo1c
6 жыл бұрын
Very clear! Thank you so much !
@HenoMarkarian
6 жыл бұрын
Thanks from Iran
@djlipomi
6 жыл бұрын
Thanks for watching!
@PavanKumarPonnekanti
Жыл бұрын
Dr. Lipomi, Thankyou for the great lecture, but, at what regime does the complex model accomodate in the relaxation modulus graph.
@klemenmlakar96
6 жыл бұрын
Superb explanation! :D
@Mike71857
2 жыл бұрын
Wow, very great lecture! I wonder for what happens microscopically at a semi-crystalline polymeric sample between the proportionality limit and the elastic limit. Why if the sample deformation is still reversible the stress in that region is not linearly proportional to strain?
@smallfish2354
5 жыл бұрын
Hi Darren, I have a question; 34:35 where you describe the behaviour of the polymers in the different regions, in the glassy region you described the behaviour as having "complete elastic recovery", wouldn't that only be the case in hypothetical purely crystalline polymers?, in reality wouldn't the amorphous regions of a given polymer still give some losses there? Many Thanks and I really enjoyed the video, Tom
@adamneil4576
3 жыл бұрын
Yes.
@nanak3363
6 жыл бұрын
at 7:20 what if we take polymer which has more ionic character than covalent character , will the graph be still same ? at 19:45 why the extra strong one is not tough one ?
@cosanostra8341
2 жыл бұрын
Hello, thank you very much for the explanation!! I did nanoidentation on a same photoresist (CAR) with 3 different layer thicknesses (4.5um, 5.2um and 6.5um) with a penetration depth of 500nn. i'v come to the conclusion that when the thickness of the photo resist is bigger, then the foto resist is harder. Do you have an idea why?? Thank you very much!!!
@sashasooshi393
2 жыл бұрын
Thank you so much for your superb explanation. I am wondering about the difference between Visco-Elasticity and Visco-Plasticity. It would be really kind if someone can please explain them to me.
@brendansullivan4872
4 жыл бұрын
Like a champ
@aniawo5119
6 жыл бұрын
Thank you sir ☺
@ramprasath9835
5 жыл бұрын
Dear Prof I need what is the right method to find viscosity for high concentrated PEO Polymer solution, I used Plate and cone method but at high conc the viscoity is fluctuating at high shear rate but at low conc it is constant
@zainnano5388
2 жыл бұрын
Sir I need all lectures about polymer chemistry that u have done.
@ramonr.5957
4 жыл бұрын
Can this model be applied to EVA (Ethylene Vinyl Acetate) ?
@romeokoolsoul
5 жыл бұрын
Hi Prof. Lipomi, I'm just wondering if you can provide a reference regarding breaking/rupture of covalent bonds at ultimate tensile stress, at your earliest convenience please . Thank you
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