Polystyrene-Z>-poly

ARGET ATRP has been successfully applied for polymerization of methyl methacrylate, ft-butyl acrylate and styrene in the presence of Sn(EH)2 (10 mol% vs. alkyl halide initiator or 0.07 mol% vs. monomer) [164,165]. For all monomers, polymerizations were well controlled using between 10 and 50 ppm of copper complexes with highly active TPMA and Me6TREN ligands. ARGET ATRP has also been utilized in the synthesis of block copolymers (poly(n-butyl acrylate)— -polystyrene and polystyrene-Z -poly(n-butyl acrylate) [164,165] and grafting... 

Here, we focus on one class ofblock copolymers synthesized by this method polystyrene-Z)-poly(vinylperfluorooctanic acid ester) block copolymers (Figure 10.33). After describing the synthesis and characterization, we will treat some properties and the potential applications of this new class ofblock copolymers. The amphiphilicity of the polymers is visualized by the ability to form micelles in diverse solvents that are characterized by dynamic light scattering (DLS). Then the use of these macromolecules for dispersion polymerization in very unpolar media is demonstrated by the polymerization of styrene in 1,1,2-trichlorotrifluoroethane (Freon 113). 

Polystyrene-Z)-poly(2-vinylpyridine)-Z>-poly(tert-butyl methacrylate). 144... 

Polyisoprene-Z)-polystyrene-Z)-poly(vinyl methyl ether). 148... 

ZOU Zou, Q.-C. and WU, L.-M., Inverse chromatographic characterization of triblock copolymer of polystyrene-Z>-poly(ethylene oxide)-Z>-polystyrene., J. Polym. Sci. Part B Polym. Phys., 45, 2015,2007. 

NUH Nuhn, H. and Klok, H.-A., Aqueous solution self-assembly of polystyrene-Z>-poly(L-lysine) diblock oligomers, Eur. Polym. J., 47, 782, 2011. 

Block copolymers in the bulk also exhibit a spectrum of morphologies analogous to the series observed for small molecule surfactants. Most of the experimental work in this regard has been carried out on polystyrene-Z -poly(isoprene)... 

The nature of crystallization within microdomains has been a controversial issue in the last decade. In the early 1960s, Skoulios et al. [131] studied poly(ethylene oxide)-6-polystyrene-Z -poly(ethylene oxide) (PEO- )-PS- >-PEO) triblock copolymers in a selective solvent for PS. They concluded that the PEO chain is perpendicular to the microdomain interface, investigating a particular case that the block copolymers were microphase separated to form a lamellar structure and where the Tg of the PS block was reduced so as to be lower than Tm of the PEO block by the solvent. 

Wang, Z., Masuo, S., Machida, S. and Itaya, A. (2005) Application of dopant-induced laser ablation to site-selective modification of sea-island structures of polystyrene-fclock-poly(4-vinylpyridine) films. Jpn. J. Appl. Phys., 44, L402-L404. 

E3 tris[polystyrene-Z)/oc -1,4-oligobutadiene-Z)/oc -poly(methyl methacrylate)]... 

E5 poly(styrene-stot-buta-l,3-diene)-Z)/oc -polystyrene-Z)/oc -l,2-polybutadiene... 

E4 polystyrene-Z)/ocA -[l,4-polybutadiene-grq/Z -poly(styrene-co-acrylonitrile)] (copolymer from styrene and acrylonitrile grafted to a 1,4-polybutadiene-polystyrene two-block copolymer at unspecified sites of some of the but-2-ene-... 

E7 polystyrene-Z)/oc - silanetetraylbis[-gra/i-poly(buta-1,3-diene)] -block-polystyrene, or poly(buta-l,3-diene)-Z)/oc -[silanetetraylbis(-gra/ polystyrene)]-Z)/ocyi -poly(buta-l,3-diene)... 

Zhang W, Shi L, An Y, Wu K, Gao L, Liu Z, Ma R, Meng Q, Zhao C, He B. Adsorption of poly(4-vinyl pyridine) unimers into polystyrene-Wocfe-poly(acrylic acid) micelles in ethanol due to hydrogen bonding. Macromolecules 2004 37 2924-2929. 

Fig.5 TEM micrographs of a polystyrene-Z7/oc/c-poly( 1,2-butadiene)-Z7/oc/c-poly(tert-butyl methacrylate) triblock copolymer that is 18% hydrolyzed and polystyrene-Z /oc/c-poly(2-vinylpyridine) diblock copolymer. S denotes polystyrene, V denotes poly(2-vinylpyridine), T/A denotes the partially (18%) hydrolyzed poly(tert-butyl methacrylate), and B denotes poly( 1,2-butadiene). Reprinted with permission from [77]. 2003 American Chemical Society...

The principles of nomenclature for copolymers are based on their structure and are given in Table 1.2, where A and B represent the names of repeating units. For example, a statistical copolymer of ethylene and propylene would be called poly(ethylene-stat-propylene), and a triblock copolymer of styrene (A) sand isoprene (B) would be called polystyrene-Z)/oeA -polyisoprene- /ocA -polystyrene. In some cases it is necessary to introduce square brackets in the nomenclature to clarify the notation. Let us see an example An alternating copolymer of styrene and maleic anhydride would be called poly[styrene-a/ (maleic anhydride)]. 

Subsequent to the attempts to compute F Z) from rj Z), described in reference 9, Williams (225) examined isothermal data on polystyrene, and Bueche and Kelley (59) reported similar calculations for polystyrene and poly (isobutylene). These investigators conclude that for... 

Poly(ethylene-flZt-propylene)-Z)-poly(ethylene-co-butylene)-Z>-polystyrene. 148... 

Birch-Hirschfield E, Foldes-Papp Z, Guhrs KH, Seliger H. Oligonucleotide synthesis on polystyrene grafted poly(tetrafluoroethylene) support. Helv Chim Acta 79 137-150, 1996. 

Prochazka K, Kiserow D, Ramireddy C, Tuzar Z, Munk P, Webber SE. Time-resolved fluorescence studies on the chain dynamics of naphthalene-labeled polystyrene-block-poly-(methacrylic acid) micelles in aqueous media. Macromolecules 1992 25 454 60. 

Dausend J, Musyanovych A, Dass M, et al. (2008) Uptake mechanism of oppositely charged fluorescent nanoparticles in HeLa cells. Macromol Biosci 8 1135-1143 Ziegler A, Landfester K, Musyanovych A (2009) Synthesis of phosphonate-functionalized polystyrene and poly(methyl methacrylate) particles and their kinetic behavior in miniemulsion polymerization. Colloid Polym Sci. http //dx.doi.Org/10.1007/s00396-009-2087-z Lorenz MR, Kohnle MV, Dass M, et al. (2008) Synthesis of fluorescent polyisoprene nanoparticles and their uptake into various cells. Macromol Biosci 8 711-727... 

QU1 Quintana, J.R., Villacampa, M., and Katime, 1., Influence of the block length on the stractuie of micelles formed by polystyrene-Z>/oc -poly(ethylene-co-propene) in octane and 5-methyl-2-hexanone,Macromo/. Chem. Phys., 194, 983, 1993. 

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