Molecule of the week published by ACS - Where you can quench your hungry for chemistry and very special molecules.

https://www.acs.org/molecule-of-the-week/archive.html?archive=All

Fundamental concept of Magnetic resonance spectroscopy.

https://www.youtube.com/watch?v=Sn3dNMv-67k

25/09/2024

Q: How do you determine the order of a particular experiment based on change in conc. vs change in time?

Q: How can one get this information from NMR titration experiments at different temperatures?

A: Find the suitable internal standard that will not be involved in the reaction, then prepare stock solutions using a known concentration of this standard. Then add the reagents, and run the NMR titration with time, and record the NMR over a time window. Run at least three different temperatures. Plot the concentration change vs time change graphs to understand which linear fit will match the above figure. Then you can calculate T1/2 as well. Once you know K, at different temperatures you can also find the activation energy (Ea) by using the Arrhenius equation.

09/01/2024

Crystallinity of polymeric materials

Heating enthalpies of different polymers when they gets 100% crystalline. Practically it is impossible to measure, so an extrapolation of flory fox equation can get this value.

The % crystallinity can be calculated from the Equation below.

Where Xc is % crystallinity, delta Hm is melting enthalpy of crystallization peak obtained from DSC. Delta Hmo is melting enthalpy of hypothetical 100% crystalline material given by TA instruments.

08/20/2024

There are hundreds of videos on extrusion, and I have chosen the best-explained one to save time for my readers.

Extruders are commonly used in polymer processing units to compound polymeric materials. Compounding is a process where additives such as plasticizers, colorants, and thermal and UV stabilizers are fed into the system along with the polymer. This process enhances the material properties, making it suitable for niche applications.