Good day!

Your spectra looks pretty the same as the spectra of melted PVDF, cooled between two KBr windows (crystallization process was not influenced by the nature of the support). Here is the referencing paper (Fig.1c):

Article Characterization of PVDF Membranes by Vibrational Spectroscopy

Best of luck in your research!

Yours sincerely,

M.Sc. Vadym Chibrikov

Department of Microstructure and Mechanics of Biomaterials

Institute of Agrophysics, Polish Academy of Sciences

Thank you for your answer Vadym!

Indeed, my spectra are very similar to those in this article. Unfortunately, there are no peaks at 1260cm-1 in the article like in my FTIR spectra.

I still need to do more research, but I thank you for your help.

Sincerely

Alban

Alban Morali I still have two options - one came out to my head, and the other I have found in paper.

1. My idea: I wonder, should we suppose that the peaks that you have marked with the red dotted line are just shifted peaks from the blue dotted line (beta phase), but for the yellow, blue, orange and grey spectra only? However, as far you are saying that everything was done on the same way, then it is not working.

2. Idea what I have found: you may be mistaken in your last statement (FTIR curves of reagents). I have found that 1260 cm-1 wavelength intensity is extremely strong for samples with low PVDF and high DMF content (see Fig.5 on link), and is attributed to the C-N asymmetric stretching vibrations of DMF:

Article FTIR studies of DMF plasticized polyvinyledene fluoride base...

Also, at the same paper on Fig.4 800 cm-1 also show appearance of some weak wavelength intensities with changing DMF:PVDF ratio, partially confirming the previous hypothesis about 1260 cm-1 wavelength intensities. However, the origin of that wavelength intensities is unclear for me.

Best of luck in your research!

Yours sincerely,

M.Sc. Vadym Chibrikov

Department of Microstructure and Mechanics of Biomaterials

Institute of Agrophysics, Polish Academy of Sciences

🇺🇦🇨🇦

Vadym Chibrikov

I totally agree with you on your ideas.

For the first one, I thought about it too, but as you said, everything was done the same way. Also, I can find this peak on different samples, always very close to 1260cm-1. For samples that I am sure were in Beta phase (industrial or electric pole), the peak is also always around 1275cm-1, so there doesn't seem to be any shift.

For the second idea, you are absolutely right, DMF shows a peak around 1260cm-1 but some things leave me doubtful. Even though there is a peak for DMF around 800cm-1, it seems to be very low so I don't know if I should consider it or not. The other thing that really makes me skeptical is the fact that these peaks are not present on the samples that I did not dry. Whereas the likelihood of me being able to scan over an area where there is still DMF left is much higher than on the dried samples. Maybe I should go futher on this explanation and try to be sure it is or not link to DMF.

Thank you very much for your time and interest in my question.

Sincerely

Alban

Good day!

The other reasoning why yo do not have intensity shift from 1275 cm-1 to 1260 cm-1 is that actually you do have intensity at 1275 cm-1, which is weakly, but seen, however, being overlayed with 1260 cm-1 wavelength intensity. Also the other fact that seems to be strange for me is that for the same curves with 1260 cm-1 and 800 cm-1 wavelength intensities you do have intensity at 1100 cm-1, that also differ from the blue and green spectra.

Here on the spectra we may see that some kind of intensity at 800 cm-1 appears with the addition of BaTiO3:

Article Hybrid fibrous (PVDF-BaTiO 3 )/ PA-11 piezoelectric patch as...

However, this peak is clearly not dedicated to BaTiO3, as far pure BaTiO3 has no intensities at 800 cm-1:

Article Study of dielectric property on BaTiO3/BADCy composite

Here, I have found that 795 cm-1 and 811 cm-1 intensities may be attributed to alpha and gamma phases:

Article Fabrication and characterization of 3D printed BaTiO 3 /PVDF...

And I suppose that this is it, since you have this very weak peaks not only on "control" green and blue spectra, but also on grey and yellow one.

As for 1260 cm-1 intensity - or it is a Nobel price, or some rookie mistake that we are missing about the methodology, since no authors report something like this to happen. If you want, you may share your steps and we will try to make another progress.

Best of luck in your research!

Yours sincerely,

M. Sc. Vadym Chibrikov

Department of Microstructure and Mechanics of Biomaterials

Institute of Agrophysics, Polish Academy of Sciences

Hello Vadym !

Sorry for the late reply.

Actually my procedure is based on this acticle. I use the same way to prepare my samples.

Article One-Step Solvent Evaporation-Assisted 3D Printing of Piezoel...

Once it's printed, for my "b4 sample" I put it in a vacuum oven at 90°C for 5h.

After that I do FTIR on some different point of my sample and also on both face.

Thanks for your help again it's very appreciated.

Have a good day

Alban

Good day, Alban Morali! Hope you are doing well.

I suppose you should obtain representative number of spectra (maybe 10-20) from different sides and batches, and average them. It should possibly reduce this noisy peaks if they are outliers. If no - so it should be a matter of some troubles with preparation technique, I suppose.

Best of luck in your research!

Yours sincerely,

M. Sc. Vadym Chibrikov

Department of Microstructure and Mechanics of Biomaterials

Institute of Agrophysics, Polish Academy of Sciences

Hello Vadym Chibrikov

Yes, I agree, this seems to be the right thing to do. I'm going to do another round of FTIR analysis on my samples and hopefully I won't be bothered by those noisy peaks.

Many thanks for your interest in my research. I also wish you good luck with yours.

Best regards

Alban

Hey Vadym Chibrikov ! Hope you're doing great.

Just to let you know, after a few more analyses, I finally found out where the peaks were coming from: a contamination due to silicone.

Indeed, for other samples I use a silicone bath and apparently I contaminated this sample by handling it.

When I look at the silicone FTIR graph, the "troublesome" peaks match.

So better late than never as they say ahah. Thanks again for your help and best wishes for this new year and your research :)

Alban

Good day, Alban Morali! Hope you are doing well.

I definitely agree with you - better later than never. You should definitely cover you experience on that contamination in your following papers - I will be waiting for :)

Best of luck in your research!

Yours sincerely,

M. Sc. Vadym Chibrikov

Department of Microstructure and Mechanics of Biomaterials

Institute of Agrophysics, Polish Academy of Sciences