PNIPA shows LCST at 32C. Below LCST it absorbs water molecules, do these H2O molecules chemically attached there or just entraped ?

10 October 2017 0 2K Report

Poly(N-Isopropylacrylamide) shows a phase transition at lower critical solution temperature (LCST) 32 C. Below 32 C it absorbs water molecules but when temperature is increased above 32 C it shows a hydrophobic character by expelling the water molecules. My interests is to know that these water molecules are really attached chemically with the PNIPA polymer chain or just entraped there ?

Badges
Science topic

More Muhammad Irfan's questions See All

What are sources/equipment's generating Alternating Magnetic field at high frequency (300 - 500 kHz)?

A nano-composite material (polymer doped with Magnetic Nanoparticles), just need to be tested to study for any heat generation in the presence of alternating magnetic field only. For that purpose...

11 December 2019 4,945 1 View

What is the difference in Mag NP's of single domain and Superparamagnetic? with heat generation point of view e.g Neel's & Brownian relaxation ?

As given in figure 3 of ref paper attached, that magnetic nanparticles of single domain and superparamagnetic type are magnetized in the same direction. My question is than what is the difference...

05 June 2018 1,205 3 View

Is it possible to distribute iron oxides Np's in water, I tried with tip-sonicator but nanopaticles quickly set at the bottom of container ?

I am trying to prepare a polymer nanocomposite solution, the plan is to first prepare polymer separately and separately distribute iron oxide nanoparticles (having no coating) in de-ionized water....

03 April 2018 818 6 View

Why PNIPAAm is a negative temperature responsive polymer ?

Please explain .

05 June 2017 9,702 4 View

Polymer composites suddenly solidifies?

I am making polymer composite by solvent mixing method. When I am trying to add filler solution in polymer solution it quickly get solidified. How to make them then uinform? It doesn't give time...

03 March 2021 7,540 4 View

How the parameters (such as Mw, Chemical bonds, polymer bland and so on) affect the mechanic property of polymer (such as storage, loss modulus) ?

Anyone can recommend any books on such topics? Thanks in advance.

02 March 2021 8,457 2 View

12% ledeburitic cold work tool steel, etched for revealing retained austenite, any help for clarifying?

Hello everyone. Given microstructure image belongs to a 12% ledeburitic cold work tool steel (annealed and tempered). The sample was etched with picral (100 mL ethanol and 4 g picric acid). I...

02 March 2021 4,119 3 View

How do I determine the degree of polymerization of PEG 400 based on NMR integration?

Hello, I am working on the photocatalytic degradation of PEG 400. I would like to know if it's possible to determine the degree on polymerization based on NMR integration, or by the MW of the...

02 March 2021 6,186 3 View

How to polymerize TEOS?

I want to polymerize TEOS on a surface. I know that NH4OH is a preferred catalyst and an alcoholic solvent should be used .But I can not find certain amounts of each material to use. Does any one...

02 March 2021 1,404 6 View

Why almost every element would be metallized in sufficiently high pressure and low temperature?

(This statement is from wikipedia, BTW). What is so special about metallic bond that is limiting high-P low-T state of a matter (as long as individual atoms exist, not white dwarf of neutron star...

02 March 2021 3,309 2 View

Ester cleavage conditions?

Hi all, I need to cleave the ester in Ethyl 2-amino-1H-imidazole-5-carboxylate to make the carboxylic acid and retrieve the product from solution to use in downstream applications of linking to...

01 March 2021 8,766 3 View

Can polymer concentrations be calculated based on the number average molecular weight?

Hello, I spin-cast two different polymers onto wafers and measure their height as a function of initial concentration. For polymer A, I have the weight-average molecular weight (Mw) as well as...

28 February 2021 7,882 2 View

POlymer+DMSO solution and moisture??

What could be the reason of moisture at the sides of Vial when I am preparing my polmyer+DMSO solution for membrane fabrication? What etiquettes I am possibly missing here?

28 February 2021 6,516 5 View

Can I use TCA instead of TFA for protein analyis in RP-HPLC?

I am trying to analyze lipase using the reverse phase-HPLC C18 column. In the literature, 0.1 % TFA was and 60% ACN was used. Can I use TCA in place of TFA? If any other methods are available to...

25 February 2021 2,388 3 View