Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
6.6
5.0
Journals
Polymers
Special Issues
Block Copolymers: Self-Assembly and Applications
share announcement

Block Copolymers: Self-Assembly and Applications

A special issue of Polymers (ISSN 2073-4360). This special issue belongs to the section "Polymer Chemistry".

Deadline for manuscript submissions: closed (25 March 2024) | Viewed by 10863

Special Issue Editor

Prof. Dr. Marinos Pitsikalis

E-Mail Website
Guest Editor
Laboratory of Industrial Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, 15771 Zografou, Greece
Interests: polymer synthesis; polymer characterization; self-assembly of copolymers in selective solvents
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

One of the most intriguing features of block copolymers is their ability to self-assemble either in bulk or in selective solvents. In bulk, the immiscibility of the constituent blocks leads to microphase separation with the formation of long-range ordered structures, such as cubic arrays, cylinders, bicontinuous phases and lamellae, with sizes comparable to the chain dimensions. In a selective solvent, i.e., a thermodynamically good solvent for the one block and precipitant for the other, block copolymers associate and form micellar aggregates. From a morphological point of view, block copolymer micelles consist of a more or less swollen core of the insoluble blocks surrounded by a corona formed by the soluble blocks. Due to their stability, variety of sizes and core–shell structure, micelles can be used in diverse practical applications, such as colloidal stabilization, latex technology, compatibilization in polymer blends, controlled drug delivery, water purification, viscosity and surface modification, etc.

Many studies, both experimental and theoretical, have been devoted to the study of micellar and associating structural parameters (critical micelle concentration, CMC, aggregation number, overall micellar size, core and shell dimensions) as well as the kinetics and thermodynamics of micellization. A combination of several experimental techniques is required to explore these parameters, including static and dynamic light scattering, neutron scattering, small-angle X-ray scattering, membrane osmometry, MO, dilute solution viscometry, electron microscopy, nuclear magnetic resonance spectroscopy, NMR, sedimentation velocity and fluorescence techniques, size exclusion chromatography, SEC, etc. Micellization is a dynamic procedure and thus can be influenced by many factors, e.g., chemical nature, composition and molecular weight of the blocks, solvent quality, pH, concentration, temperature, etc.

An enormous number of studies have been conducted using di- and triblock copolymers. However, recent advances in synthetic polymer chemistry have enabled the preparation of various well-defined complex macromolecular topologies stimulating efforts to link polymer architecture and supramolecular assembly of copolymers in selective solvents. From these reports, the macromolecular architecture has emerged as a very important parameter for the manipulation of micellar properties, thereby providing a new tool for tuning micellization behavior and for designing materials with specific applications. As a result, tapered copolymers, star-block, linear-dendritic, cyclic, miktoarm stars, graft, H-, super H-,  π-shaped and more complex brush-like copolymers have been studied in selective solvents, confirming the tremendous impact of macromolecular architecture on micellization properties.

This Special Issue will focus on recent developments on the self-assembly behavior of amphiphilic copolymers and their applications. Special interest will be given to the effect of macromolecular architecture on the micellization behavior.

Prof. Dr. Marinos Pitsikalis
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Polymers is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2700 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • synthesis of micellar structures
  • advanced characterization techniques of micellar structures
  • thermodynamics of micellization
  • kinetics of micellization
  • applications of polymeric micellar systems
  • effect of macromolecular architecture on the self-assembly behavior
  • theoretical approaches to the micellization behavior

Published Papers (6 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

22 pages, 3023 KiB  
Article
Synthesis and Micellization Behavior of Amphiphilic Block Copolymers of Poly(N-vinyl Pyrrolidone) and Poly(Benzyl Methacrylate): Block versus Statistical Copolymers
by Nikoletta Roka and Marinos Pitsikalis
Polymers 2023, 15(9), 2225; https://doi.org/10.3390/polym15092225 - 08 May 2023
Cited by 1 | Viewed by 1752
Abstract
Block copolymers of N-vinyl pyrrolidone (NVP) and benzyl methacrylate (BzMA), PNVP-b-PBzMA, were prepared by RAFT polymerization techniques and sequential addition of monomers. The copolymers were characterized by Size Exclusion Chromatography (SEC) and NMR spectroscopy. Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA) [...] Read more.
Block copolymers of N-vinyl pyrrolidone (NVP) and benzyl methacrylate (BzMA), PNVP-b-PBzMA, were prepared by RAFT polymerization techniques and sequential addition of monomers. The copolymers were characterized by Size Exclusion Chromatography (SEC) and NMR spectroscopy. Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA) and Differential Thermogravimetry (DTG) were employed to study the thermal properties of these copolymers. The micellization behavior in THF, which is a selective solvent for the PBzMA blocks, was examined. For comparison the self-assembly properties of the corresponding statistical copolymers, PNVP-stat-PBzMA, were studied. In addition, the association behavior in aqueous solutions was analyzed for the block copolymers, PNVP-b-PBzMA. In this case, the solvent is selective for the PNVP blocks. Dilute solution viscometry, static (SLS) and dynamic light scattering (DLS) were employed as the tools to investigate the micellar assemblies. The efficient encapsulation of the hydrophobic curcumin within the micellar core of the supramolecular structures in aqueous solutions was demonstrated by UV-Vis spectroscopy and DLS measurements. Full article
(This article belongs to the Special Issue Block Copolymers: Self-Assembly and Applications)
►▼ Show Figures

Figure 1

19 pages, 6084 KiB  
Article
UV-Accelerated Synthesis of Gold Nanoparticle–Pluronic Nanocomposites for X-ray Computed Tomography Contrast Enhancement
by Deizilene S. B. Gomes, Leonardo G. Paterno, Aline B. S. Santos, Debora P. P. Barbosa, Beatriz M. Holtz, Maysa R. Souza, Rafaianne Q. Moraes-Souza, Aisel V. Garay, Laise R. de Andrade, Patricia P. C. Sartoratto, Damien Mertz, Gustavo T. Volpato, Sonia M. Freitas and Maria A. G. Soler
Polymers 2023, 15(9), 2163; https://doi.org/10.3390/polym15092163 - 01 May 2023
Cited by 2 | Viewed by 2106
Abstract
Eco-friendly chemical methods using FDA-approved Pluronic F127 (PLU) block copolymer have garnered much attention for simultaneously forming and stabilizing Au nanoparticles (AuNPs). Given the remarkable properties of AuNPs for usage in various fields, especially in biomedicine, we performed a systematic study to synthesize [...] Read more.
Eco-friendly chemical methods using FDA-approved Pluronic F127 (PLU) block copolymer have garnered much attention for simultaneously forming and stabilizing Au nanoparticles (AuNPs). Given the remarkable properties of AuNPs for usage in various fields, especially in biomedicine, we performed a systematic study to synthesize AuNP-PLU nanocomposites under optimized conditions using UV irradiation for accelerating the reaction. The use of UV irradiation at 254 nm resulted in several advantages over the control method conducted under ambient light (control). The AuNP-PLU-UV nanocomposite was produced six times faster, lasting 10 min, and exhibited lower size dispersion than the control. A set of experimental techniques was applied to determine the structure and morphology of the produced nanocomposites as affected by the UV irradiation. The MTT assay was conducted to estimate IC50 values of AuNP-PLU-UV in NIH 3T3 mouse embryonic fibroblasts, and the results suggest that the sample is more compatible with cells than control samples. Afterward, in vivo maternal and fetal toxicity assays were performed in rats to evaluate the effect of AuNP-PLU-UV formulation during pregnancy. Under the tested conditions, the treatment was found to be safe for the mother and fetus. As a proof of concept or application, the synthesized Au:PLU were tested as contrast agents with an X-ray computed tomography scan (X-ray CT). Full article
(This article belongs to the Special Issue Block Copolymers: Self-Assembly and Applications)
►▼ Show Figures

Figure 1

13 pages, 2641 KiB  
Article
Reversible Thermo-Optical Response Nanocomposites Based on RAFT Symmetric Triblock Copolymers (ABA) of Acrylamide and N-Isopropylacrylamide and Gold Nanoparticles
by Nery M. Aguilar, Jose Manuel Perez-Aguilar, Valeria J. González-Coronel, Hugo Martínez-Gutiérrez, Teresa Zayas Pérez, Enrique González-Vergara, Brenda L. Sanchez-Gaytan and Guillermo Soriano-Moro
Polymers 2023, 15(8), 1963; https://doi.org/10.3390/polym15081963 - 21 Apr 2023
Cited by 1 | Viewed by 1732
Abstract
The development of composite materials with thermo-optical properties based on smart polymeric systems and nanostructures have been extensively studied. Due to the fact of its ability to self-assemble into a structure that generates a significant change in the refractive index, one of most [...] Read more.
The development of composite materials with thermo-optical properties based on smart polymeric systems and nanostructures have been extensively studied. Due to the fact of its ability to self-assemble into a structure that generates a significant change in the refractive index, one of most attractive thermo-responsive polymers is poly(N-isopropylacrylamide) (PNIPAM), as well as its derivatives such as multiblock copolymers. In this work, symmetric triblock copolymers of polyacrylamide (PAM) and PNIPAM (PAMx-b-PNIPAMy-b-PAMx) with different block lengths were prepared by reversible addition−fragmentation chain-transfer polymerization (RAFT). The ABA sequence of these triblock copolymers was obtained in only two steps using a symmetrical trithiocarbonate as a transfer agent. The copolymers were combined with gold nanoparticles (AuNPs) to prepare nanocomposite materials with tunable optical properties. The results show that copolymers behave differently in solution due to the fact of variations in their composition. Therefore, they have a different impact on the nanoparticle formation process. Likewise, as expected, an increase in the length of the PNIPAM block promotes a better thermo-optical response. Full article
(This article belongs to the Special Issue Block Copolymers: Self-Assembly and Applications)
►▼ Show Figures

Figure 1

13 pages, 1551 KiB  
Article
Synthesis, Characterization, Conformation in Solution, and Thermoresponsiveness of Polymer Brushes of methoxy[oligo (propylene glycol)-block-oligo(ethylene glycol)]methacrylate and N-[3-(dimethylamino)propyl]methacrylamide Obtained via RAFT Polymerization
by Maria Simonova, Denis Kamorin, Alexander Filippov and Oleg Kazantsev
Polymers 2023, 15(7), 1641; https://doi.org/10.3390/polym15071641 - 25 Mar 2023
Cited by 3 | Viewed by 1315
Abstract
The thermo- and pH-responsive polymer brushes based on methoxy[oligo(propyleneglycol)8-block-oligo(ethyleneglycol)8]methacrylate with different concentrations of N-[3-(dimethylamino)propyl]methacrylamide (from 0% to 20%) were synthesized via RAFT polymerization. The “grafting-through” approach was used to prepare the low-molar-mass dispersion samples (Mw/M [...] Read more.
The thermo- and pH-responsive polymer brushes based on methoxy[oligo(propyleneglycol)8-block-oligo(ethyleneglycol)8]methacrylate with different concentrations of N-[3-(dimethylamino)propyl]methacrylamide (from 0% to 20%) were synthesized via RAFT polymerization. The “grafting-through” approach was used to prepare the low-molar-mass dispersion samples (Mw/Mn ≈ 1.3). Molar masses and hydrodynamic characteristics were obtained using static and dynamic light scattering and viscometry. The solvents used were acetonitrile, DMFA, and water. The molar masses of the prepared samples ranged from 40,000 to 60,000 g·mol–1. The macromolecules of these polymer brushes were modeled using a prolate revolution ellipsoid or a cylinder with spherical ends. In water, micelle-like aggregates were formed. Critical micelle concentrations decreased with the content of N-[3-(dimethylamino)propyl]methacrylamide. Molecular brushes demonstrated thermo- and pH-responsiveness in water–salt solutions. It was shown that at a given molecular mass and at close pH values, the increase in the number of N-[3-(dimethylamino)propyl]methacrylamide units led to an increase in phase separation temperatures. Full article
(This article belongs to the Special Issue Block Copolymers: Self-Assembly and Applications)
►▼ Show Figures

Figure 1

25 pages, 4985 KiB  
Article
Phosphine-Functionalized Core-Crosslinked Micelles and Nanogels with an Anionic Poly(styrenesulfonate) Shell: Synthesis, Rhodium(I) Coordination and Aqueous Biphasic Hydrogenation Catalysis
by Hui Wang, Chantal J. Abou-Fayssal, Christophe Fliedel, Eric Manoury and Rinaldo Poli
Polymers 2022, 14(22), 4937; https://doi.org/10.3390/polym14224937 - 15 Nov 2022
Cited by 3 | Viewed by 1604
Abstract
Stable latexes containing unimolecular amphiphilic core-shell star-block polymers with a triphenylphosphine(TPP)-functionalized hydrophobic core and an outer hydrophilic shell based on anionic styrenesulfonate monomers have been synthesized in a convergent three-step strategy by reversible addition-fragmentation chain-transfer (RAFT) polymerization, loaded with [RhCl(COD)]2 and applied [...] Read more.
Stable latexes containing unimolecular amphiphilic core-shell star-block polymers with a triphenylphosphine(TPP)-functionalized hydrophobic core and an outer hydrophilic shell based on anionic styrenesulfonate monomers have been synthesized in a convergent three-step strategy by reversible addition-fragmentation chain-transfer (RAFT) polymerization, loaded with [RhCl(COD)]2 and applied to the aqueous biphasic hydrogenation of styrene. When the outer shell contains sodium styrenesulfonate homopolymer blocks, treatment with a toluene solution of [RhCl(COD)]2 led to undesired polymer coagulation. Investigation of the interactions of [RhCl(COD)]2 and [RhCl(COD)(PPh3)] with smaller structural models of the polymer shell functions, namely sodium p-toluenesulfonate, sodium styrenesulfonate, and a poly(sodium styrenesulfonate) homopolymer in a biphasic toluene/water medium points to the presence of equilibrated Rh-sulfonate interactions as the cause of coagulation by inter-particle cross-linking. Modification of the hydrophilic shell to a statistical copolymer of sodium styrenesulfonate and poly(ethylene oxide) methyl ether methacrylate (PEOMA) in a 20:80 ratio allowed particle loading with the generation of core-anchored [RhCl(COD)TPP] complexes. These Rh-loaded latexes efficiently catalyze the aqueous biphasic hydrogenation of neat styrene as a benchmark reaction. The catalytic phase could be recovered and recycled, although the performances in terms of catalyst leaching and activity evolution during recycles are inferior to those of equivalent nanoreactors based on neutral or polycationic outer shells. Full article
(This article belongs to the Special Issue Block Copolymers: Self-Assembly and Applications)
►▼ Show Figures

Graphical abstract

15 pages, 3324 KiB  
Article
Syndiotactic Poly(4-methyl-1-pentene)-Based Stereoregular Diblock Copolymers: Synthesis and Self-Assembly Studies
by Yu-Chuan Sung, Pei-Sun Huang, Shih-Hung Huang, Yeo-Wan Chiang and Jing-Cherng Tsai
Polymers 2022, 14(22), 4815; https://doi.org/10.3390/polym14224815 - 09 Nov 2022
Cited by 4 | Viewed by 1661
Abstract
Syndiotactic poly(4-methyl-1-pentene) (sP4M1P)-based stereoregular diblock copolymers, namely sP4M1P-b-polystyrene and sP4M1P-b-polymethylmethacrylate, were prepared from an α-bromoester-capped sP4M1P macroinitiator, which was chain extended with styrene and methyl methacrylate, respectively, via the atom transfer radical polymerization reaction. The α-bromoester-capped sP4M1P was generated [...] Read more.
Syndiotactic poly(4-methyl-1-pentene) (sP4M1P)-based stereoregular diblock copolymers, namely sP4M1P-b-polystyrene and sP4M1P-b-polymethylmethacrylate, were prepared from an α-bromoester-capped sP4M1P macroinitiator, which was chain extended with styrene and methyl methacrylate, respectively, via the atom transfer radical polymerization reaction. The α-bromoester-capped sP4M1P was generated by the esterification of hydroxyl-capped sP4M1P with α-bromoisobutyryl bromide. The hydroxyl-capped sP4M1P was synthesized by inducing a selective chain transfer reaction to aluminum during the syndiospecific polymerization of 4-methyl-1-pentene in the presence of a syndiospecific metallocene catalyst. As stereoregular diblock copolymers are difficult to prepare using existing methods, the current study offers an effective process for the preparation of sP4M1P-based stereoregular diblock copolymers. These copolymers were found to have well-defined architectures and they can undergo molecular self-assembly into ordered nanostructures, as evidenced by small-angle X-ray scattering analyses. Full article
(This article belongs to the Special Issue Block Copolymers: Self-Assembly and Applications)
►▼ Show Figures

Graphical abstract

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-6
Back to TopTop