Self-Organization Process of Ordered Structures in Linear and Star Poly(styrene)−Poly(isoprene) Block Copolymers:  Gaussian Models and Mesoscopic Parameters of Polymeric Systems

2007 ◽  
Vol 111 (40) ◽  
pp. 11756-11764 ◽  
Author(s):  
César Soto-Figueroa ◽  
Luis Vicente ◽  
José-Manuel Martínez-Magadán ◽  
María-del-Rosario Rodríguez-Hidalgo
Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1412
Author(s):  
Eunkyung Ji ◽  
Cian Cummins ◽  
Guillaume Fleury

The ability of bottlebrush block copolymers (BBCPs) to self-assemble into ordered large periodic structures could greatly expand the scope of photonic and membrane technologies. In this paper, we describe a two-step synthesis of poly(l-lactide)-b-polystyrene (PLLA-b-PS) BBCPs and their rapid thin-film self-assembly. PLLA chains were grown from exo-5-norbornene-2-methanol via ring-opening polymerization (ROP) of l-lactide to produce norbornene-terminated PLLA. Norbonene-terminated PS was prepared using anionic polymerization followed by a termination reaction with exo-5-norbornene-2-carbonyl chloride. PLLA-b-PS BBCPs were prepared from these two norbornenyl macromonomers by a one-pot sequential ring opening metathesis polymerization (ROMP). PLLA-b-PS BBCPs thin-films exhibited cylindrical and lamellar morphologies depending on the relative block volume fractions, with domain sizes of 46–58 nm and periodicities of 70–102 nm. Additionally, nanoporous templates were produced by the selective etching of PLLA blocks from ordered structures. The findings described in this work provide further insight into the controlled synthesis of BBCPs leading to various possible morphologies for applications requiring large periodicities. Moreover, the rapid thin film patterning strategy demonstrated (>5 min) highlights the advantages of using PLLA-b-PS BBCP materials beyond their linear BCP analogues in terms of both dimensions achievable and reduced processing time.


1967 ◽  
Vol 40 (5) ◽  
pp. 1526-1528
Author(s):  
Ed Vanzo

Abstract Anionically prepared block copolymers of butadiene and styrene exhibit solution properties which result from a two dimensional ordering of the polymer molecules. The most notable of these properties is the iridescent colors of toluene solutions which are dependent on concentration and abruptly change on mechanical deformation. Electron micrographs of the surface of cast films indicate that the ordered structure is retained to some degree in the solid state.


1999 ◽  
Vol 56 (10) ◽  
pp. 609-616
Author(s):  
Masashi KUNITAKE ◽  
Akihiro OHIRA ◽  
Shinobu UEMURA ◽  
Masayo SAKATA ◽  
Chuichi HIRAYAMA

RSC Advances ◽  
2014 ◽  
Vol 4 (45) ◽  
pp. 23585 ◽  
Author(s):  
Shu-Chi Tsao ◽  
Chieh-Tsung Lo

Author(s):  
Анна Нориковна Адамян ◽  
Алена Константиновна Кучурова ◽  
Александра Ивановна Иванова ◽  
Максим Дмитриевич Малышев ◽  
Виктор Анатольевич Герасин ◽  
...  

Выполнены реологические, структурные и антибактериальные исследования гидрогелей, получаемых на основе L-цистеина, ацетата серебра и полигексаметиленгуанидин гидрохлорида (ПГМГ-ГХ). Установлено, что водные растворы на основе L-цистеина и ацетата серебра хорошо смешиваются с водным раствором ПГМГ-ГХ, образуя прозрачные гидрогели. Предложена модель строения пространственной сетки геля. Показана высокая антимикробная активность гидрогеля по отношению к тест-культурам патогенных и условно-патогенных микроорганизмов. Rheological, structural, and antibacterial studies of hydrogels based on L-cysteine, silver acetate, and polyhexamethylene guanidine hydrochloride (PHMG-GC) have been carried out. It was found that aqueous solutions based on L-cysteine and silver acetate mix well with an aqueous solution of PHMG-GC, forming transparent hydrogels. A model of the structure of the spatial grid of the gel is proposed. High antimicrobial activity of the hydrogel was shown in relation to test cultures of pathogenic and opportunistic microorganisms.


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