Self-assembly of hydrophobic-amphiphilic diblock copolymers in solution

Abstract Thermoresponsive polymers are usually characterized by a locally amphiphilic chain structure and their self-assembly in solution is controlled, in particular, by the surface activity of the monomer units or side chains. We theoretically study the condensed state of a single diblock copolymer molecule consisting of a hydrophobic block and amphiphilic block with hydrophobic groups in the backbone and pendant polar groups. The equilibrium parameters of the polymer globules of different shapes are determined using the mean-field approach to determine the most favorable structure. Morphological diagrams of condensed macromolecules are presented depending on the chain length, amphiphilic block fraction, interaction parameters, and pendant volume and length. The diagrams are compared with those of a copolymer molecule with the same fraction of amphiphilic monomer units which are regularly distributed along the chain. The diblock copolymer molecule is found to form a single spherical or flattened particle, with the core from the hydrophobic block, or a granular micelle consisting of spherical or nearly spherical particles, in agreement with the experimental data in the literature. The optimal chain parameters for self-assembly into a stable single core-shell particle are predicted.

Thermo-responsive metallo-supramolecular gels based on terpyridine end-functionalized amphiphilic diblock copolymers

MRS Proceedings ◽

10.1557/opl.2013.496 ◽

2013 ◽

Vol 1499 ◽

Cited By ~ 1

Author(s):

Jérémy Brassinne ◽

Charles-André Fustin ◽

Jean-François Gohy

Keyword(s):

Mechanical Properties ◽

Diblock Copolymer ◽

Self Assembly ◽

Micellar Solution ◽

Diblock Copolymers ◽

Solution Temperature ◽

Selective Solvent ◽

Critical Solution Temperature ◽

Terpyridine Ligands ◽

ABSTRACTA thermo-responsive hydrogel was prepared on the basis of terpyridine endfunctionalized polystyrene-block-poly(N-isopropylacrylamide) diblock copolymer. As a first level of assembly, the copolymer was dissolved in a selective solvent to yield micelles bearing terpyridine ligands at the extremity of the coronal chains. The second level of self-assembly was triggered upon addition of metal ions to the micellar solution. Mechanical properties of the accordingly obtained micellar gel were finally characterized by rotational rheometry, below and above the lower critical solution temperature.

Cyclic azobenzene-containing amphiphilic diblock copolymers: solution self-assembly and unusual photo-responsive behaviors

Polymer Chemistry ◽

10.1039/c5py00246j ◽

2015 ◽

Vol 6 (16) ◽

pp. 3009-3013 ◽

Cited By ~ 11

Author(s):

Beibei Chen ◽

Zhao Wang ◽

Jinjie Lu ◽

Xian Yang ◽

Yong Wang ◽

...

Keyword(s):

Diblock Copolymer ◽

Self Assembly ◽

Diblock Copolymers ◽

Amphiphilic Diblock Copolymer ◽

Spherical Micelles ◽

Self Assembled ◽

A novel amphiphilic diblock copolymer containing cyclic-azobenzene has been synthesized and self-assembled into spherical micelles which show unusual photo-responsive behaviors.

Synthesis and Characterization of Temperature-Responsive N-Cyanomethylacrylamide-Containing Diblock Copolymer Assemblies in Water

Polymers ◽

10.3390/polym13244424 ◽

2021 ◽

Vol 13 (24) ◽

pp. 4424

Author(s):

Nicolas Audureau ◽

Fanny Coumes ◽

Clémence Veith ◽

Clément Guibert ◽

Jean-Michel Guigner ◽

...

Keyword(s):

Diblock Copolymer ◽

Self Assembly ◽

Diblock Copolymers ◽

Colloidal Stability ◽

Aqueous Dispersion ◽

Degree Of Polymerization ◽

Solution Temperature ◽

Thermoresponsive Polymers ◽

Aqueous Synthesis ◽

Reversible Addition

We have previously demonstrated that poly(N-cyanomethylacrylamide) (PCMAm) exhibits a typical upper-critical solution temperature (UCST)-type transition, as long as the molar mass of the polymer is limited, which was made possible through the use of reversible addition-fragmentation chain transfer (RAFT) radical polymerization. In this research article, we use for the first time N-cyanomethylacrylamide (CMAm) in a typical aqueous dispersion polymerization conducted in the presence of poly(N,N-dimethylacrylamide) (PDMAm) macroRAFT agents. After assessing that well-defined PDMAm-b-PCMAm diblock copolymers were formed through this aqueous synthesis pathway, we characterized in depth the colloidal stability, morphology and temperature-responsiveness of the dispersions, notably using cryo-transmission electron microscopy (cryo-TEM), dynamic light scattering (DLS), small angle X-ray scattering (SAXS) and turbidimetry. The combined analyses revealed that stable nanometric spheres, worms and vesicles could be prepared when the PDMAm block was sufficiently long. Concerning the thermoresponsiveness, only diblocks with a PCMAm block of a low degree of polymerization (DPn,PCMAm < 100) exhibited a UCST-type dissolution upon heating at low concentration. In contrast, for higher DPn,PCMAm, the diblock copolymer nano-objects did not disassemble. At sufficiently high temperatures, they rather exhibited a temperature-induced secondary aggregation of primary particles. In summary, we demonstrated that various morphologies of nano-objects could be obtained via a typical polymerization-induced self-assembly (PISA) process using PCMAm as the hydrophobic block. We believe that the development of this aqueous synthesis pathway of novel PCMAm-based thermoresponsive polymers will pave the way towards various applications, notably as thermoresponsive coatings and in the biomedical field.

Self-assembly of Amphiphilic Diblock Copolymers Induced by Liquid-Liquid Phase Separation

Chinese Journal of Polymer Science ◽

10.1007/s10118-021-2563-6 ◽

2021 ◽

Author(s):

Jia-Lu Bai ◽

Dan Liu ◽

Rong Wang

Keyword(s):

Phase Separation ◽

Liquid Phase ◽

Self Assembly ◽

Diblock Copolymers ◽

Liquid Phase Separation ◽

Liquid Liquid Phase Separation

Self-Assemble Behavior of Amphiphilic Diblock Copolymer of Methoxy Poly (Ethylene Glycol)/Polyester

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.295-297.11 ◽

2011 ◽

Vol 295-297 ◽

pp. 11-15

Author(s):

Hao Zhou ◽

Qing Hong Liang ◽

Xiang Ke Shi ◽

Li Hua Lu ◽

Li Qun Zhang ◽

...

Keyword(s):

Polyethylene Glycol ◽

Light Scattering ◽

Diblock Copolymer ◽

Diblock Copolymers ◽

Average Diameter ◽

Core Shell ◽

Amphiphilic Diblock Copolymer ◽

Methoxy Polyethylene Glycol ◽

Solution Polycondensation

Amphiphilic diblock copolymers based on methoxy polyethylene glycol (MePEG), 1, 6-hexanediol and maleic anhydride with different molar composition were synthesized by solution polycondensation. Self-assemble behavior of amphiphilic diblock copolymer in different solvents by dialyzing technique was discussed. The micelle morphologhy was observed by TEM. It was found that well core-shell MePEG1900/Polyester 2162 copolymer nanoparticles can be formed by self-assemble in acetone solution. In addition, the size of nanospheres measured using dynamic light scattering exhibited a narrow monodisphere size distribution and an average diameter in the ranger of less than 200nm.

A coarse-grained model for PCL: conformation, self-assembly of MePEG-b-PCL amphiphilic diblock copolymers

Molecular Simulation ◽

10.1080/08927022.2016.1233550 ◽

2016 ◽

Vol 43 (2) ◽

pp. 92-101 ◽

Cited By ~ 9

Author(s):

Abhinav S. Raman ◽

Aleksey Vishnyakov ◽

Y. C. Chiew

Keyword(s):

Self Assembly ◽

Diblock Copolymers ◽

Coarse Grained ◽

Coarse Grained Model ◽

Self-assembly of linear diblock copolymers in selective solvents: from single micelles to particles with tri-continuous inner structures

Soft Matter ◽

10.1039/d0sm00402b ◽

2020 ◽

Vol 16 (26) ◽

pp. 6056-6062 ◽

Cited By ~ 1

Author(s):

Xianggui Ye ◽

Bamin Khomami

Keyword(s):

Diblock Copolymer ◽

Self Assembly ◽

Large Scale ◽

Diblock Copolymers ◽

Dissipative Particle Dynamics ◽

Particle Dynamics ◽

The Self ◽

Selective Solvent ◽

Selective Solvents

Large-scale dissipative particle dynamics (DPD) simulations have been performed to investigate the self-assembly of over 20 000 linear diblock copolymer chains in a selective solvent.

1998 E.W.R. Steacie Award Lecture Asymmetric amphiphilic block copolymers in solution: a morphological wonderland

Canadian Journal of Chemistry ◽

10.1139/v99-141 ◽

1999 ◽

Vol 77 (8) ◽

pp. 1311-1326 ◽

Cited By ~ 176

Author(s):

Neil S Cameron ◽

Muriel K Corbierre ◽

Adi Eisenberg

Keyword(s):

Self Assembly ◽

Diblock Copolymers ◽

Amphiphilic Block Copolymers ◽

Polymer Composition ◽

Selective Solvents ◽

Thermodynamic And Kinetic Parameters ◽

Systematic Understanding ◽

Selection Of ◽

Qualitative Discussion

Asymmetric amphiphilic diblock copolymers self-assemble in selective solvents. Since 1995, when we first reported the systematic preparation of a sequence of various "crew-cut" aggregate morphologies from this class of copolymer in solution (1), we have identified a vast array of structures and have begun a detailed investigation of the thermodynamic and kinetic parameters that induce morphogenesis. Not only spheres, rods, bilayer and bicontinuous architectures, as well as inverted structures are observed, but also a selection of mixed, combined and much more complex aggregates is documented. All of these aggregates have a phase-separated insoluble core and a crew-cut soluble corona. Thus, all parameters that permit selective modification of the component of either phase or of the interface provide a window for morphological control. By carefully adjusting the polymer chain environment, it has been possible to develop a systematic understanding of morphogenic parameters, which include, among others, polymer composition, common solvent, initial concentration, temperature, type and concentration of added ions, method of preparation, and added homopolymer. To date, more than 30 publications have appeared in the literature from our group alone on this subject. One of the problems inherent with such a complicated system is the taxonomy or classification: which morphologies correspond to equilibrium positions and which are intermediate or trapped? An attempt at a logical presentation of the observed aggregates is given, preceded by a qualitative discussion of the thermodynamic framework for this system. Where possible, the transitions between morphologies are explained in the context of the thermodynamic parameters. Finally, parallels are drawn between the copolymer aggregates and biological architectures.Key words: crew-cut, morphology, block copolymer, self-assembly, amphiphile.

Synthesis of amphiphilic diblock copolymers of isotactic polystyrene-block-isotactic poly(p-hydroxystyrene) using a titanium complex with an [OSSO]-type bis(phenolate) ligand and sequential monomer addition

RSC Advances ◽

10.1039/c7ra01450c ◽

2017 ◽

Vol 7 (32) ◽

pp. 19885-19893 ◽

Cited By ~ 6

Author(s):

QiHua Zhou ◽

HuaQing Liang ◽

WanChu Wei ◽

ChunFeng Meng ◽

YongJiang Long ◽

...

Keyword(s):

Diblock Copolymer ◽

Diblock Copolymers ◽

Amphiphilic Diblock Copolymer ◽

Isotactic Polystyrene ◽

Titanium Complex ◽

Sequential Monomer Addition ◽

Hydrolysis Of

A novel amphiphilic diblock copolymer of iPS-b-iP(p-HOS) is prepared resulting from the hydrolysis of iPS-b-iP(p-TBDMSOS) synthesized by sequential monomer addition with [OSSO]-type titanium complex 1/MAO.