How to remove the KOH from ethanolic etherification without using extraction method?

Etherification was carried out between aromatic -OH group and alkyl chloride in the presence of ethanolic KOH. The precursor is a bulky dye compound that consists of an aromatic -OH group and an...

04 May 2019 2,639 4 View

Why this polymeric DSC have three peaks and no dip?

The sample is polymer and I sent this sample for analysis. The obtained DSC curve was kind of unexpected. The curve looks different from what I have studied and seen before. 1. Why the glass...

31 December 2017 8,521 9 View

Is it possible to get the higher molecular weight(Mw) first before getting the lower Mw during the Soxhlet extraction of the polymer?

I tried to extract the polymer through Soxhlet extraction. According to some references, the sequence for the organic solvents is methanol, acetone, hexane, toluene, and chloroform. The...

11 December 2017 4,920 3 View

Can I use cellulose Soxhlet thimble instead of glass fibre thimble for the Soxhlet extraction in polymerization?

I read that most previous studies used glass fibre thimble instead of the cellulose thimble. The solvents are methanol, acetone, hexane, toluene, dichloromethane, chloroform. If I use cellulose...

04 May 2017 1,408 3 View

Why the entire FTIR spectrum shifted to the left after dimerization?

01 February 2017 9,964 3 View

How can I get freshly powdered KOH from commercially bought KOH pallets?

The KOH absorb atmospheric moisture quite fast when I manually powdered it.

01 February 2017 3,914 4 View

Which is the suitable NMR solvent for compound that does not dissolve in DMSO-d6 and CDCl3?

I would like to scan NMR for a compound name : 4,4'-dibromo-2,2'-diaminobiphenyl. According to some papers, the NMR solvents used are either CDCl3 or DMSO-d6. However, when I try to dissolve my...

31 December 2016 2,950 10 View

What is the purpose of adding HBr in bromination? Hbr/Br2 system.

Is the HBr was added to prevent the formation of HBr as by-product from Br2 during the reaction (minimize the wastage of Br2)? And to move the reaction forwards faster?

11 December 2016 4,878 7 View

Why DMSO is used even though the compounds are soluble in DMF?

I get to know that the solvent DMF is technically similar to the DMSO for organic synthesis, just that DMSO can dissolve more compounds than the DMF. Is there any special reason that DMSO is used...

10 November 2016 6,668 7 View

Can the commercial reusable dry ice packs be used as dry ice in my experiment?

I have a few packs of reusable dry ice-gel packs. They are sent along with the chemicals in a box for keeping the chemicals cool. Is it possible for me to use that "gel" as dry ice to reach the...

09 October 2016 9,004 5 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 can I selectively dry etch Ti on a polymer substrate?

24 February 2021 5,378 1 View

How to do a surface treatment of uncoated TiO2 with polymer?

Basically, I would like to know how to treat or coat on the uncoated bare TiO2 (Ti-OH rich) surface with polymer which has anchoring groups in the polymer structure like trimethoxygroups. What is...

21 February 2021 4,657 6 View