How to purify mono-BOC-ethylenediamine or N-tert-butoxycarbonylaminoethylamine by Column cromatography?

How to purify mono-BOC-ethylenediamine or N-tert-butoxycarbonylaminoethylamine (EDA-BOC) by Column cromatography? I used ethylacetate (100% ) over silica gel to purify but it does not work....

09 October 2017 1,640 4 View

How to calculate % yield and reactivity ratio in poly(Styrene methylmethacrylte) synthesis ?

31 December 2016 328 4 View

How to remove TFA salt ?

03 April 2016 5,833 7 View

How to confirm BOC deprotection by TFA ?

02 March 2016 692 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

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

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

How to reduce residual stresses in MD simulation?

I am working on a preparation of representative polymeric structures of some popular polymers, such as polyimide or PTFE for MD simulation, during which a single nitrogen or oxygen atom will be...

24 February 2021 8,105 3 View

How to identify what type of fillers are in a polymer?

Hello everyone, I have some PHAs blended with fillers and nucleating agents, yet I don't know what kind of fillers or nucleating agents. The producer has shut down and there's no way to get in...

24 February 2021 1,356 8 View

How to handle studies which report perfect effect sizes in a meta-analysis using Pearson's r?

I'm in the process of updating a meta-analysis and in one of the new studies, effect sizes are reported as Tau-U. Two of the effect sizes are reported as Tau-U = 1.00. I am using Andy Field's...

24 February 2021 2,265 3 View

How can I selectively dry etch Ti on a polymer substrate?

24 February 2021 5,378 1 View