Tag: Polymer characterization

Amphiphilic Poly(dimethylsiloxane-ethylene-propylene oxide)-polyisocyanurate Cross-Linked Block Copolymers in a Membrane Gas Separation

Block copolymers, including multiblock copolymers of an amphiphilic nature, because of their ability to form various supramolecular structures are attracting a lot of research interest these days. The direct influence on the supramolecular organization of block copolymers is a way of controlling both the mechanical and physicochemical properties of polymer materials obtained on this basis. *

In the article “Amphiphilic Poly(dimethylsiloxane-ethylene-propylene oxide)-polyisocyanurate Cross-Linked Block Copolymers in a Membrane Gas Separation” Ilsiya M. Davletbaeva, Ilgiz M. Dzhabbarov, Askhat M. Gumerov, Ilnaz I. Zaripov, Ruslan S. Davletbaev, Artem A. Atlaskin, Tatyana S. Sazanova and Ilya V. Vorotyntsev describe how they investigated Multiblock copolymers obtained based on PPEG, D4 (octamethylcyclotetrasiloxane ) and TDI ( 2,4-toluene diisocyanate ).*

The authors studied the realized polymers as membrane materials for the separation of gas mixtures containing CO2/CH4 and CO2/N2 and went on to show that polymers with a cellular supramolecular structure exhibit lower permeability for CO2 in comparison with polymeric film materials whose supramolecular structure is constructed on the basis of the “core-shell” principle. *

It was shown in the above mentioned article that polymers are promising as silica-based membrane materials for the separation of gas mixtures containing CO2/CH4 and CO2/N2. *

As the polymer material investigated for this article is rather soft NanoWorld Pointprobe® FMR AFM probes with a typical force constant of around 2.8 N/m were used for the analysis by atomic force microscopy of the membrane surface.*

Figure 15 from Ilsiya M. Davletbaeva et al “Amphiphilic Poly(dimethylsiloxane-ethylene-propylene oxide)-polyisocyanurate Cross-Linked Block Copolymers in a Membrane Gas Separation”: AFM Images. (a): [PPEG]:[TDI] = 1:10; (b): [PPEG]:[D4]:[TDI] = 1:15:10; (c): [PPEG]:[D4]:[TDI] = 1:15:10 [ASiP] = 0.2 wt.%, (d): [PPEG]:[D4]:[TDI] = 1:15:10 [ASiP] = 0.4 wt.%. NanoWorld Pointprobe® FMR AFM probes were used.
Figure 15 from Ilsiya M. Davletbaeva et al “Amphiphilic Poly(dimethylsiloxane-ethylene-propylene oxide)-polyisocyanurate Cross-Linked Block Copolymers in a Membrane Gas Separation”:
AFM Images. (a): [PPEG]:[TDI] = 1:10; (b): [PPEG]:[D4]:[TDI] = 1:15:10; (c): [PPEG]:[D4]:[TDI] = 1:15:10 [ASiP] = 0.2 wt.%, (d): [PPEG]:[D4]:[TDI] = 1:15:10 [ASiP] = 0.4 wt.%.

*Ilsiya M. Davletbaeva, Ilgiz M. Dzhabbarov, Askhat M. Gumerov, Ilnaz I. Zaripov, Ruslan S. Davletbaev, Artem A. Atlaskin, Tatyana S. Sazanova, and Ilya V. Vorotyntsev
Amphiphilic Poly(dimethylsiloxane-ethylene-propylene oxide)-polyisocyanurate Cross-Linked Block Copolymers in a Membrane Gas Separation
Membranes 2021, 11(2), 94
DOI: https://doi.org/10.3390/membranes11020094

Please follow this external link to read the full article: https://www.mdpi.com/2077-0375/11/2/94/htm#

Open Access : The article “Amphiphilic Poly(dimethylsiloxane-ethylene-propylene oxide)-polyisocyanurate Cross-Linked Block Copolymers in a Membrane Gas Separation” by Ilsiya M. Davletbaeva, Ilgiz M. Dzhabbarov, Askhat M. Gumerov, Ilnaz I. Zaripov, Ruslan S. Davletbaev, Artem A. Atlaskin, Tatyana S. Sazanova, and Ilya V. Vorotyntsev is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit https://creativecommons.org/licenses/by/4.0/.

Direct Observation of Long-Chain Branches in a Low-Density Polyethylene

The properties of a polymer change significantly depending on the structure of the polymer chain, particularly, with branched structures, depending on the number of branches and the length of the branch.* However, the long-chain branch (LCB) structure of polyethylene was unclear, due particularly to the complex polymer structure and the limitations of its analysis methods.

In their study “Direct Observation of Long-Chain Branches in a Low-Density Polyethylene” Ken-ichi Shinohara, Masahiro Yanagisawa and Yuu Makida measured the chain length of LCBs and the distance between branch points of LDPE by atomic force microscopy.*

The article mentions the use of NanoWorld Ultra-Short Cantilevers (USC) for high speed atomic force microscopy ( AFM probe type USC-F1.2-k0.15 ) for the single-molecule imaging by atomic force microscopy .*

Figure 1 from “Direct Observation of Long-Chain Branches in a Low-Density Polyethylene “ by K. Shinohara et al.: Direct measurement of LCB in a tubular LDPE (F200-0 fractionated). (A) AFM image of a single molecule of LDPE on mica in DMTS at 25 °C. X: 279 nm, Y: 209 nm, Z: 18 nm. (B) Length of each chain of LDPE. (C) A wire model of self-shrinking structure of polymer chain of LDPE. Main chain: red wire. LCB: black wire. The model was created to be one tenth of the length of the extended chain based on AFM observation (B), MD simulation (Fig. S1), and the molecular weight determined by SEC-MALLS-Visc experiments (see Fig. 2).
Figure 1 from “Direct Observation of Long-Chain Branches in a Low-Density Polyethylene “ by K. Shinohara et al.: Direct measurement of LCB in a tubular LDPE (F200-0 fractionated). (A) AFM image of a single molecule of LDPE on mica in DMTS at 25 °C. X: 279 nm, Y: 209 nm, Z: 18 nm. (B) Length of each chain of LDPE. (C) A wire model of self-shrinking structure of polymer chain of LDPE. Main chain: red wire. LCB: black wire. The model was created to be one tenth of the length of the extended chain based on AFM observation (B), MD simulation (Fig. S1), and the molecular weight determined by SEC-MALLS-Visc experiments (see Fig. 2).

*Ken-ichi Shinohara, Masahiro Yanagisawa, Yuu Makida
Direct Observation of Long-Chain Branches in a Low-Density Polyethylene
Nature Scientific Reportsvolume 9, Article number: 9791 (2019)
doi: https://doi.org/10.1038/s41598-019-46035-9

Please follow this external link for the full article: https://rdcu.be/bJY7S

Open Access: The article «Direct Observation of Long-Chain Branches in a Low-Density Polyethylene» by Ken-ichi Shinohara, Masahiro Yanagisawa and Yuu Makida is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.

Direct observation of dynamic interaction between a functional group in a single SBR chain and an inorganic matter surface

In the article  “Direct observation of dynamic interaction between a functional group in a single SBR chain and an inorganic matter surface” Ken-ichi Shinohara and Yuu Makida use atomic force microscopy (AFM) video imaging to closely investigate the behaviour of functionalized and unmodified styrene-butadiene rubber (SBR), as models for tire rubber, on mica surfaces.

“Using AFM video imaging, we tracked the behavior of individual SBR polymer chains on mica surfaces to reveal how polymer modification affects the interaction of SBR with mica surfaces. We measured the diffusion coefficients and spring constants of single SBR polymer chains for the first time, demonstrating that it is possible to parameterize the relationship between the molecular dynamic structure of a polymer and rubber properties of the vulcanized compound.”*

NanoWorld Ultra-Short Cantilevers (USC) for Fast-/High-Speed AFM  ( USC-F1.2-k0.15 ) were used

Figure 3 from “Direct observation of dynamic interaction between a functional group in a single SBR chain and an inorganic matter surface” by Ken-ichi Shinohara & Yuu Makida: (A) Single-molecule imaging of the structure of two isolated polymer chains of carboxyl-functionalized styrene-butadiene rubber (SBR) on mica under n-octylbenzene at 25 ± 1 °C (Movie S5). Snapshot AFM image of a fast-scanning atomic force microscopy (AFM) movie; X: 200 nm, Y: 150 nm, Z: 7.2 nm. Rate: 5.0 fps. (B) A snapshot of all-atom MD simulated structure of a single chain of carboxyl-functionalized SBR (CPK model) in n-octylbenzene as a solvent. Dynamic globular (ball-like) structures were formed partially in a SBR chain. The position of carboxyl group was indicated by an arrow. The backbone was displayed in purple. Solvent molecules are indicated by line model and hydrogen atoms are omitted for simplified to view. NanoWorld USC-F1.2-k0.15 AFM probes were used
Figure 3 from “Direct observation of dynamic interaction between a functional group in a single SBR chain and an inorganic matter surface” by Ken-ichi Shinohara & Yuu Makida: (A) Single-molecule imaging of the structure of two isolated polymer chains of carboxyl-functionalized styrene-butadiene rubber (SBR) on mica under n-octylbenzene at 25 ± 1 °C (Movie S5). Snapshot AFM image of a fast-scanning atomic force microscopy (AFM) movie; X: 200 nm, Y: 150 nm, Z: 7.2 nm. Rate: 5.0 fps. (B) A snapshot of all-atom MD simulated structure of a single chain of carboxyl-functionalized SBR (CPK model) in n-octylbenzene as a solvent. Dynamic globular (ball-like) structures were formed partially in a SBR chain. The position of carboxyl group was indicated by an arrow. The backbone was displayed in purple. Solvent molecules are indicated by line model and hydrogen atoms are omitted for simplified to view.

*Ken-ichi Shinohara & Yuu Makida
Direct observation of dynamic interaction between a functional group in a single SBR chain and an inorganic matter surface
Nature Scientific Reports, volume 8, Article number: 13982 (2018)
DOI: https://doi.org/10.1038/s41598-018-32382-6

For the full article please follow this external link: https://rdcu.be/bbERH

The article “Direct observation of dynamic interaction between a functional group in a single SBR chain and an inorganic matter surface” by Ken-ichi Shinohara & Yuu Makida is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.