Interactions in block copolymers in solution: The effect of hetero-contacts on the segmental interactions in block copolymers of poly(isoprene : styrene) in solution

1969 ◽  
Vol 22 (8) ◽  
pp. 1649 ◽  
Author(s):  
JR Urwin

Binary cluster integrals or excluded volumes for chemically different segment pairs in block copolymers of poly(isoprene : styrene) have been calculated from the equation derived by Froelich and Benoit for a two- sequence block copolymer. Expansion factors have been recalculated assuming a linear relation for [η]θ with respect to composition employing published values for polystyrene and polyisoprene. The results are discussed in relation to possible conformations of block copolymers.

2021 ◽  
Author(s):  
Isamu Akiba ◽  
Kazuo Sakurai

AbstractBlock copolymers are well recognized as excellent nanotools for delivering hydrophobic drugs. The formulation of such delivery nanoparticles requires robust characterization and clarification of the critical quality attributes correlating with the safety and efficacy of the drug before applying to regulatory authorities for approval. Static solution scattering from block copolymers is one such technique. This paper first outlines the theoretical background and current models for analyzing this scattering and then presents an overview of our recent studies on block copolymers.


2020 ◽  
Vol 5 (10) ◽  
pp. 1642-1657
Author(s):  
Cian Cummins ◽  
Guillaume Pino ◽  
Daniele Mantione ◽  
Guillaume Fleury

Recently engineered high χ-low N block copolymers for nanolithography are evaluated. Synthetic routes together with thin film processing strategies are highlighted that could enable the relentless scaling for logic technologies at sub-10 nanometres.


2017 ◽  
Vol 8 (34) ◽  
pp. 4983-4987 ◽  
Author(s):  
Jawaher A. Alfurhood ◽  
Hao Sun ◽  
Christopher P. Kabb ◽  
Bryan S. Tucker ◽  
James H. Matthews ◽  
...  

We report nanoassemblies based on block copolymers of N-(2-hydroxypropyl)methacrylamide (HPMA) in which drug cleavage enhances the biological compatibility of the original polymer carrier by regeneration of HPMA units.


2008 ◽  
pp. 391-417 ◽  
Author(s):  
Carlos Rodrguez ◽  
Arturo Lpez-Quintela ◽  
Md. Hemayet Uddin ◽  
Kenji Aramaki ◽  
Hironobu Kunieda

2014 ◽  
Vol 41 (10) ◽  
pp. 45-50
Author(s):  
A.A. Alekseev ◽  
A.V. Lobanov ◽  
V.S. Osipchik ◽  
V.S. Glukhovskoi ◽  
V.M. Aristov ◽  
...  

The structure and properties of block copolymers (BCPs) of styrene and butadiene of grade StiroTEP-70 (styrene:butadiene = 70:30, Mw/Mn = 1.43–1.45) are discussed. Analysis of IR spectra enables the BCP to be treated as polystyrene-stat-copoly(butadiene/styrene/1,2-butadiene)-polystyrene. It is suggested that the absorption band at 542 cm-1 be considered as characteristic when identifying polymers with extensive polystyrene phases. At temperatures of 190–230°C, the BCP is partially crosslinked, and at 260°C it breaks down. The BCP is processed well at temperatures up to 200°C.


2020 ◽  
Vol 1000 ◽  
pp. 324-330
Author(s):  
Sri Agustina ◽  
Masayoshi Tokuda ◽  
Hideto Minami ◽  
Cyrille Boyer ◽  
Per B. Zetterlund

The self-assembly of block copolymers has attracted attention for many decades because it can yield polymeric nanoobjects with a wide range of morphologies. Membrane emulsification is a fairly novel technique for preparation of various types of emulsions, which relies on the dispersed phase passing through a membrane in order to effect droplet formation. In this study, we have prepared polymeric nanoparticles of different morphologies using self-assembly of asymmetric block copolymers in connection with membrane emulsification. Shirasu Porous Glass (SPG) membranes has been employed as the membrane emulsification equipment, and poly (oligoethylene glycol acrylate)-block-poly (styrene) (POEGA-b-PSt) copolymers prepared via RAFT polymerization. It has been found that a number of different morphologies can be achieved using this novel technique, including spheres, rods, and vesicles. Interestingly, the results have shown that the morphology can be controlled not only by adjusting experimental parameters specific to the membrane emulsification step such as membrane pore size and pressure, but also by changing the nature of organic solvent. As such, this method provides a novel route to these interesting nanoobjects, with interesting prospects in terms of exercising morphology control without altering the nature of the block copolymer itself.


2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Fatime Eren Erol ◽  
Deniz Sinirlioglu ◽  
Sedat Cosgun ◽  
Ali Ekrem Muftuoglu

Synthesis of fluorinated amphiphilic block copolymers via atom transfer radical polymerization (ATRP) and Cu(I) catalyzed Huisgen 1,3-dipolar cycloaddition (CuAAC) was demonstrated. First, a PEGMA and MMA based block copolymer carrying multiple side-chain acetylene moieties on the hydrophobic segment for postfunctionalization was carried out. This involves the synthesis of a series of P(HEMA-co-MMA) random copolymers to be employed as macroinitiators in the controlled synthesis of P(HEMA-co-MMA)-block-PPEGMA block copolymers by using ATRP, followed by a modification step on the hydroxyl side groups of HEMA via Steglich esterification to afford propargyl side-functional polymer, alkyne-P(HEMA-co-MMA)-block-PPEGMA. Finally, click coupling between side-chain acetylene functionalities and 2,3,4,5,6-pentafluorobenzyl azide yielded fluorinated amphiphilic block copolymers. The obtained polymers were structurally characterized by1H-NMR,19F-NMR, FT-IR, and GPC. Their thermal characterizations were performed using DSC and TGA.


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