EPJ Plus Highlight - Does that “green” plasticiser make my PVC flexible enough for you?

A snapshot of the simulated PVC/DOP system at a 30 wt% PVC concentration after minimization. Red, green, yellow and blue spheres represent O, Cl, C, and H atoms, respectively.

A study of an eco-friendly solvent helping to make PVC plastic more flexible reveals the molecular-level interaction of hydrogen bonds between the two ingredients

What gives plastic objects their flexibility and reduces their brittleness is the concentration of plasticiser. For example, a chemical solvent of the phthalate family called DOP is often used. The trouble is there are concerns that phthalates present health risks. So there is a demand for more alternatives. Now, scientists from China have examined the effect of using DEHHP, a new eco-friendly plasticiser, used in combination with PVC. For a plasticiser to work, there has to be adequate hydrogen bonding with the plastic. By combining experiments and simulations, the team revealed why the polymer-solvent hydrogen bonding interaction's strength decreases with dilution at a molecular level—which is a phenomenon also observed in the DOP-PVC combination. These findings have been published in EPJ Plus by Yang Liu from Nanjing University and colleagues.

The team studied the polymer-solvent interactions at various temperatures and concentrations. Specifically, they looked at the effects of DEHHP concentration in relation to hydrogen bonding interactions, as a means to evaluate its ability to make plastics flexible. This eco-friendly plasticiser is an ideal model because it has only one kind of hydrogen bonding interaction—between polymer and solvent—and is free of other potentially interfering hydrogen bonding interactions.

They found in stretching experiments that when the temperature increases or the PVC concentration decreases, the interactions between polymer and solvent were weaker in the PVC-DEHHP mix than in the PVC-DOP combination.

Then, they used what they refer to as low-field hydrogen Nuclear Magnetic Resonance (NMR). This shows that the number of polymer-solvent complexes decreased as temperature increased. Furthermore, they looked into simulations of the molecular dynamics to study the role of polymer-solvent hydrogen bonding interactions. They demonstrated that when the temperature was high or the PVC concentration was low, faster molecular motions resulted. This also led to the disassociation of the hydrogen bonds in the hydrogen bonding system.

This was our first experience of publishing with EPJ Web of Conferences. We contacted the publisher in the middle of September, just one month prior to the Conference, but everything went through smoothly. We have had published MNPS Proceedings with different publishers in the past, and would like to tell that the EPJ Web of Conferences team was probably the best, very quick, helpful and interactive. Typically, we were getting responses from EPJ Web of Conferences team within less than an hour and have had help at every production stage.
We are very thankful to Solange Guenot, Web of Conferences Publishing Editor, and Isabelle Houlbert, Web of Conferences Production Editor, for their support. These ladies are top-level professionals, who made a great contribution to the success of this issue. We are fully satisfied with the publication of the Conference Proceedings and are looking forward to further cooperation. The publication was very fast, easy and of high quality. My colleagues and I strongly recommend EPJ Web of Conferences to anyone, who is interested in quick high-quality publication of conference proceedings.

On behalf of the Organizing and Program Committees and Editorial Team of MNPS-2019, Dr. Alexey B. Nadykto, Moscow State Technological University “STANKIN”, Moscow, Russia. EPJ Web of Conferences vol. 224 (2019)

ISSN: 2100-014X (Electronic Edition)

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