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Abstract The effect of vortex‐induced mechanical stresses on the fluorescent properties of dye‐containing poly(ethylene glycol)‐block‐poly(lactic acid) (PEG‐b‐PLA) block copolymer micelles has been investigated. PEG‐b‐PLA block copolymer micelles containing fluorescent dyes, 3,3′‐dioctadecyloxacarbocyanine perchlorate (DiO) and/or 1,1′‐dioctadecyl‐3,3,3′,3′‐tetramethylindocarbocyanine perchlorate (DiI), are prepared by a simple one‐step procedure that involves the self‐assembly of block copolymers and spontaneous incorporation of hydrophobic dyes into the core of the micelles. Upon vortexing, the micelle dispersion samples showed a decrease in fluorescence intensity in a rotational speed‐ and time‐dependent manner. The results demonstrated that the vortexing can alter the fluorescent properties of the dye‐containing PEG‐b‐PLA block copolymer micelle dispersion samples, suggesting the potential utility of block copolymer micelles as a mechanical stress‐responsive nanomaterial.
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Ethyl cellulose- block -poly(benzyl glutamate) block copolymer compatibilizers for ethyl cellulose/poly(ethylene terephthalate) blends
A block copolymer with the structure ethylcellulose-block-poly(benzy glutamate) was synthesizedviaring-opening polymerization and used as a compatibilizer to produce blends of ethylcellulose and poly(ethylene terephthalate).
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- PAR ID:
- 10580241
- Editor(s):
- Luscombe, Christine; Anastasaki, Athina; Du_Prez, Filip; Frey, Holger; Hu, Rongrong; Klausen, Rebekka; Konkolewicz; Li, Zhibo; Li, Zi_Chen; Sardon, Haritz
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Polymer Chemistry
- Volume:
- 15
- Issue:
- 34
- ISSN:
- 1759-9954
- Page Range / eLocation ID:
- 3501 to 3509
- Subject(s) / Keyword(s):
- compatibilization polysaccharide biopolymer polyester
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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ABSTRACT Recent interest in manipulating the chemistry of block copolymers (BCPs) to manage the covarying properties necessary to meet manufacturing criteria in nanolithography has resulted in the development and expansion of the A‐block‐(B‐random‐C) BCP architecture, where the random block allows for the decoupling of thermodynamic and wetting properties. Previous reports of such BCPs have used click chemistry to create the desired random block, but all such instances possess additional functional groups that are susceptible to undesirable side reactions upon annealing, such as cross‐linking and surface grafting. This study reports the substitution reaction of polystyrene‐block‐poly(pentafluorophenyl methacrylate) (PS‐b‐PPFMA) with primary amines. The resulting methacrylamide structure of the functionalized random block has only an amide linkage between the attached functional group and the polymer backbone, thereby omitting any sources of side reactions within the BCP. The outcomes of this report also demonstrate the enhanced thermal stability of these materials by virtue of their stable amide bonds. A range of random copolymer compositions is assessed to develop BCPs in which the random block has approximately the same surface energy as the PS block. These BCPs can self‐assemble into perpendicular lamellae and are therefore promising candidates for directed self‐assembly.more » « less
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1039/D4PY00688G
