Self-assembly behavior of amphiphilic diblock copolymer PS-b-P4VP in CO2-expanded liquids was written by Cheng, Xiaomeng;Jiao, Dongxia;Liang, Zhihao;Wei, Jinjin;Li, Hongping;Yang, Junjiao. And the article was included in Wuli Huaxue Xuebao in 2018.Application In Synthesis of Benzyl benzodithioate This article mentions the following:
The self-assembly behavior of block copolymers and their assembled micellar morphologies have attracted considerable attention because of their potential applications in biomedicine, drug delivery, and catalysis. Herein we report that CO2-expanded liquids (CXLs) facilitate the morphol. control of the self-assembled aggregates (SAAs) of polystyrene-block-poly(4-vinylpyridine) (PS-b-P4VP) formed in CO2-expanded toluene. The anti-solvent effect of CXLs can successfully regulate the self-assembly behavior of the copolymer PS-b-P4VP. The difference in amphiphilicity between PS and P4VP block is reduced with increasing pressure of CO2-expanded toluene owing to the anti-solvent effect of CO2. In addition, this diminished difference may influence the interfacial tension at the P4VP core-PS corona interface, which triggers a morphol. change of the aggregate. The SAA structures are dependent on both CXL pressure and copolymer composition under the exptl. conditions implemented in this work. The morphol. evolution of the SAAs in CXLs exhibits remarkable pressure dependence. As the pressure increases, the SAA structure of PS168-b-P4VP420 transits from primarily spheres (0.1 MPa) to mostly interconnected rods (6.35 MPa), the SAA of PS790-b-P4VP263 evolves from small vesicles (0.1 MPa) to large compound vesicles (LCVs, 6.35 MPa), whereas the PS153-b-P4VP1530 counterpart switches from large compound micelles (LCMs, 0.1 MPa) to mainly large compound vesicles (LCVs, 6.35 MPa). Moreover, transmission electron microscopy (TEM) data on constant copolymer composition implies that the packing parameter p of the SAAs increases with the CXLs pressure. Especially, under the exptl. conditions employed in this work, we find that the major factor controlling the SAA shape in conventional toluene is the copolymer composition, while in CO2-expanded toluene, the dominant factor controlling the SAA morphol. might be the varying contact area between shell-forming segment PS and the CXLs with increasing pressure. This work proves that the CXL method facilitates the modulation of morphol. of the SAAs, and opens a green route for the development of new nano-functional materials. In the experiment, the researchers used many compounds, for example, Benzyl benzodithioate (cas: 27249-90-7Application In Synthesis of Benzyl benzodithioate).
Benzyl benzodithioate (cas: 27249-90-7) belongs to esters. Volatile esters with characteristic odours are used in synthetic flavours, perfumes, and cosmetics. Certain volatile esters are used as solvents for lacquers, paints, and varnishes. Cyclic esters are called lactones, regardless of whether they are derived from an organic or inorganic acid. One example of an organic lactone is γ-valerolactone.Application In Synthesis of Benzyl benzodithioate
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