scholarly journals Rotation Dynamics of Star Block Copolymers under Shear Flow

Polymers ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 860 ◽  
Author(s):  
Diego Jaramillo-Cano ◽  
Christos Likos ◽  
Manuel Camargo
Keyword(s):  
Block Copolymers ◽  
Diblock Copolymers ◽  
Building Blocks ◽  
Laboratory Frame ◽  
Rotational Frequency ◽  
Geometrical Approach ◽  
Soft Systems ◽  
Self Assembling ◽  
Star Block Copolymers ◽  
Physical And Chemical

Star block-copolymers (SBCs) are macromolecules formed by a number of diblock copolymers anchored to a common central core, being the internal monomers solvophilic and the end monomers solvophobic. Recent studies have demonstrated that SBCs constitute self-assembling building blocks with specific softness, functionalization, shape and flexibility. Depending on different physical and chemical parameters, the SBCs can behave as flexible patchy particles. In this paper, we study the rotational dynamics of isolated SBCs using a hybrid mesoscale simulation technique. We compare three different approaches to analyze the dynamics: the laboratory frame, the non-inertial Eckart’s frame and a geometrical approximation relating the conformation of the SBC to the velocity profile of the solvent. We find that the geometrical approach is adequate when dealing with very soft systems, while in the opposite extreme, the dynamics is best explained using the laboratory frame. On the other hand, the Eckart frame is found to be very general and to reproduced well both extreme cases. We also compare the rotational frequency and the kinetic energy with the definitions of the angular momentum and inertia tensor from recent publications.

scholarly journals Rotation Dynamics of Star Block Copolymers under Shear Flow

2018 ◽  
Author(s):  
Diego Jaramillo-Cano ◽  
Christos N. Likos ◽  
Manuel Camargo
Keyword(s):  
Block Copolymers ◽  
Diblock Copolymers ◽  
Building Blocks ◽  
Laboratory Frame ◽  
Rotational Frequency ◽  
Geometrical Approach ◽  
Soft Systems ◽  
Self Assembling ◽  
Star Block Copolymers ◽  
Physical And Chemical

Star block-copolymers (SBCs) are macromolecules formed by a number of diblock copolymers anchored to a common central core, being the internal monomers solvophilic and the end monomers solvophobic. Recent studies have demonstrated that SBCs constitute a self-assembling building blocks with specific softness, functionalization, shape, and flexibility. Depending on different physical and chemical parameters the SBCs can behave as flexible patchy particles. In this paper, we study the rotational dynamics of isolated SBCs using a hybrid mesoscale simulation technique. We compare three different approaches to analyse the dynamics: the laboratory frame, the non-inertial Eckart's frame, and a geometrical approximation relating the conformation of the SBC to the velocity profile of the solvent. We find that the geometrical approach is adequate when dealing with very soft systems while in the opposite extreme, the dynamics is best explained using the laboratory frame. On the other hand, the Eckart frame is found to be very general and to reproduced well both extreme cases. We also compare the rotational frequency and the kinetic energy with the definitions of the angular momentum and inertia tensor different from recent publications.

Amphiphilic Diblock Copolymers of Poly(glycidol) with Biodegradable Polyester/Polycarbonate. Organocatalytic One-Pot ROP and Self-Assembling Property

2021 ◽  
Author(s):  
Tingyu He ◽  
Atsushi Narumi ◽  
Yanqiu Wang ◽  
Liang Xu ◽  
Shin-ichiro Sato ◽  
...  
Keyword(s):  
Block Copolymers ◽  
Diblock Copolymers ◽  
Amphiphilic Block Copolymers ◽  
Synthetic Method ◽  
Biodegradable Polyester ◽  
One Pot ◽  
Self Assembling ◽  
Amphiphilic Diblock Copolymers

A synthetic method for a series of poly(glycidol) (PG)-based amphiphilic block copolymers is presented with an emphasis on the catalyst switch method from an organic superbase (t-Bu-P4) to another with...

Star-Shaped Copolymers Based on Poly(N-vinylcaprolactam) and their Use as Nanocarriers of Methotrexate

2017 ◽  
Vol 70 (12) ◽  
pp. 1291 ◽  
Author(s):  
Norma A. Cortez-Lemus ◽  
Angel Licea-Claverie
Keyword(s):  
Polyethylene Glycol ◽  
Block Copolymers ◽  
Diblock Copolymers ◽  
Raft Polymerization ◽  
Drug Loading ◽  
Gel Permeation Chromatography ◽  
Solution Temperature ◽  
Star Copolymers ◽  
Vis Spectroscopy ◽  
Star Block Copolymers

Star-shaped poly(N-vinylcaprolactam)-block-poly(ethylhexylacrylate)-block-polyethylene glycol (PNVCL-b-PEHA-b-PEG) triblock copolymers and star-shaped poly(N-vinylcaprolactam)-block-polyethylene glycol (PNVCL-b-PEG) diblock copolymers were synthesized by reversible addition–fragmentation chain transfer (RAFT) polymerization. The resulting star block copolymers were characterized using 1H NMR and UV-vis spectroscopy, gel permeation chromatography, and dynamic light scattering. The star-shaped PNVCL-b-PEG and PNVCL-b-PEHA-b-PEG block copolymers self-assemble spontaneously into aggregates in water. The aggregates formed ranged from ~17 to 135 nm in diameter and were used to encapsulate methotrexate (MTX). It was observed that the aggregates from PNVCL-b-PEHA-b-PEG copolymers exhibited a higher drug loading and a lower release of MTX (19 wt-% and 54 %) as compared with star copolymers without PEHA (5 wt-% and 81 %) after 24 h at a temperature below their lower critical solution temperature values.

Synthesis and Solution-state Assembly or Bulk State Thiol-ene Crosslinking of Pyrrolidinone- and Alkene-functionalized Amphiphilic Block Fluorocopolymers: From Functional Nanoparticles to Anti-fouling Coatings

2010 ◽  
Vol 63 (8) ◽  
pp. 1159 ◽  
Author(s):  
Jun Ma ◽  
Jeremy W. Bartels ◽  
Zhou Li ◽  
Ke Zhang ◽  
Chong Cheng ◽  
...  
Keyword(s):  
Block Copolymers ◽  
Diblock Copolymers ◽  
Raft Polymerization ◽  
Building Blocks ◽  
Ene Reactions ◽  
Reversible Addition ◽  
Complex Building ◽  
Crosslinked Networks ◽  
Amphiphilic Diblock Copolymers ◽  
Synthetic Methodologies

With an ever increasing interest in the combined functionality and versatility of materials, increasing demands are placed on synthetic methodologies by which to produce such materials. This work demonstrates the preparation of block copolymers having fluorocarbon content, pyrrolidinone units, and alkene groups as complex building blocks for the assembly of discrete nanoparticles in solution and, alternatively, transformation into sophisticated crosslinked networks. Reversible addition–fragmentation chain transfer (RAFT) polymerization is a facile tool for the synthesis of well-defined polymers containing imbedded side-chain functionalities. In this work, the synthesis of well-defined multifunctional fluorinated polymers bearing pendant pyrrolidinone groups, and block copolymers bearing both pyrrolidinone and alkenyl groups on different segments was achieved, by using RAFT polymerizations of unique bifunctional monomers. Upon micellization, the amphiphilic diblock copolymers were transformed into regioselectively-functionalized nanoparticles. Further transformations of pyrrolidinone- and alkene-dual functionalized-block copolymers into complex amphiphilic networks were accomplished by highly efficient UV-induced thiol-ene reactions. Whether as discrete nanoparticles or nanoscopically-segregated crosslinked networks, these materials have great potential for several diverse technologies, including as anti-fouling materials.

Defect structures and ordering behaviours of diblock copolymers self-assembling on spherical substrates

Soft Matter ◽  
2014 ◽  
Vol 10 (35) ◽  
pp. 6713-6721 ◽  
Author(s):  
Liangshun Zhang ◽  
Liquan Wang ◽  
Jiaping Lin
Keyword(s):  
Block Copolymers ◽  
Diblock Copolymers ◽  
Lamellar Phase ◽  
Defect Structures ◽  
Self Assembling ◽  
Cylindrical Phase

The Landau–Brazovskii theory is employed to explore defect structures and ordering behaviors of block copolymers confined on spherical substrates. Isolated disclinations and scars are formed in the cylindrical phase. The defect structures of hedgehog, spiral and quasi-baseball are produced in the lamellar phase.

Combinatorial Peptide Libraries for Selecting Inorganic-Binding Proteins: A Step in Molecular Biomimetics

2003 ◽  
Vol 773 ◽  
Author(s):  
C. Tamerler ◽  
S. Dinçer ◽  
D. Heidel ◽  
N. Karagûler ◽  
M. Sarikaya
Keyword(s):  
Binding Proteins ◽  
Building Blocks ◽  
Molecular Engineering ◽  
Inorganic Materials ◽  
Combinatorial Peptide Libraries ◽  
Self Assembling ◽  
Complex Functions ◽  
Recent Developments ◽  
Specific Proteins ◽  
Molecular Biomimetics

AbstractProteins, one of the building blocks in organisms, not only control the assembly in biological systems but also provide most of their complex functions. It may be possible to assemble materials for practical technological applications utilizing the unique advantages provided by proteins. Here we discuss molecular biomimetic pathways in the quest for imitating biology at the molecular scale via protein engineering. We use combinatorial biology protocols to select short polypeptides that have affinity to inorganic materials and use them in assembling novel hybrid materials. We give an overview of some of the recent developments of molecular engineering towards this goal. Inorganic surface specific proteins were identified by using cell surface and phage display technologies. Examples of metal and metal oxide specific polypeptides were represented with an emphasis on certain level of specificities. The recognition and self assembling characteristics of these inorganic-binding proteins would be employed in develeopment of hybrid multifunctional materials for novel bio- and nano-technological applications.

Factors Affecting Molecular Self-Assembly and Its Mechanism

2012 ◽  
Vol 9 (1) ◽  
pp. 43 ◽  
Author(s):  
Hueyling Tan
Keyword(s):  
Self Assembly ◽  
Building Blocks ◽  
Molecular Engineering ◽  
Molecular Structures ◽  
Polymer Science ◽  
New Approach ◽  
Factors Affecting ◽  
Dna Structures ◽  
Self Assembling ◽  
Wide Range

Molecular self-assembly is ubiquitous in nature and has emerged as a new approach to produce new materials in chemistry, engineering, nanotechnology, polymer science and materials. Molecular self-assembly has been attracting increasing interest from the scientific community in recent years due to its importance in understanding biology and a variety of diseases at the molecular level. In the last few years, considerable advances have been made in the use ofpeptides as building blocks to produce biological materials for wide range of applications, including fabricating novel supra-molecular structures and scaffolding for tissue repair. The study ofbiological self-assembly systems represents a significant advancement in molecular engineering and is a rapidly growing scientific and engineering field that crosses the boundaries ofexisting disciplines. Many self-assembling systems are rangefrom bi- andtri-block copolymers to DNA structures as well as simple and complex proteins andpeptides. The ultimate goal is to harness molecular self-assembly such that design andcontrol ofbottom-up processes is achieved thereby enabling exploitation of structures developed at the meso- and macro-scopic scale for the purposes oflife and non-life science applications. Such aspirations can be achievedthrough understanding thefundamental principles behind the selforganisation and self-synthesis processes exhibited by biological systems.

Mechanical and Structural Consequences of Associative Dynamic Cross-Linking in Acrylic Diblock Copolymers

2019 ◽  
Author(s):  
Jacob Ishibashi ◽  
Yan Fang ◽  
Julia Kalow
Keyword(s):  
Block Copolymers ◽  
Rheological Properties ◽  
Diblock Copolymers ◽  
Cross Linking ◽  
Statistical Copolymer

<p>Block copolymers are used to construct covalent adaptable networks that employ associative exchange chemistry (vitrimers). The resulting vitrimers display markedly different nanostructural, thermal and rheological properties relative to those of their statistical copolymer-derived counterparts. This study demonstrates that prepolymer sequence is a versatile strategy to modify the properties of vitrimers.</p>

Sign in / Sign up

Export Citation Format

Share Document