Block copolymer penta

Block copolymerization was carried out in the bulk polymerization of St using 18 as the polymeric iniferter. The block copolymer was isolated with 63-72 % yield by solvent extraction. In contrast with the polymerization of MMA with 6, the St polymerization with 18 as the polymeric iniferter does not proceed via the livingradical polymerization mechanism,because the co-chain end of the block copolymer 19 in Eq. (22) has the penta-substituted ethane structure, of which the C-C bond will dissociate less frequently than the C-C bond of hexa-substituted ethanes, e.g., the co-chain end of 18. This result agrees with the fact that the polymerization of St with 6 does not proceed through a living radical polymerization mechanism. Therefore, 18 is suitably used for the block copolymerization of 1,1-diubstituted ethylenes such as methacrylonitrile and alkyl methacrylates [83]. 

Lee et al. reported the preparation of nanoporous crystalline sheets of penta-p-phenylene using a (oligomeric) block copolymer with a cleavable juncture approach in 2004 [63]. These so-called rod-coil block copolymers of penta-p-phenylene and PPO can self-assemble to give layered phases that contain sheets of perforated crystalline penta-p-phenylene in which the perforations are filled with PPO [64]. The PPO segment is covalently bound to the... 

The concept was further extended to the preparation of PtBA-l7-PIB-l7-PSt (ABC) triblock and amphiphilic penta-block copolymers based on PIB. ° ... 

OF and Lipase P were also shown to aggregate with block copolymers made of poly[(A-acetylimino)ethylene] and poly[(A-pentanoylimino)ethylene], with about 30% increased activity for the ester hydrolysis and 200% increased activity for the ester synthesis in aqueous solutions compared to the native enzymes. The activity of egg white lysozyme located in the core of PEG—poly(o ,j8-aspartic acid) micelles was investigated by colorimetric methods and revealed an increase for p-nitrophenyl-penta-A-acetyl-/ -chitopentaoside as substrate. By the determination of kinetic constants of enzymatic reaction, it was demonstrated that the increase in the enzymatic activity was... 

Figure 16.15 TEM images for bulk state morphologies of PS- -PFS (a-c), PFS- -PMMA (d) and PMMA- -PFS-Z -PS-Z -PFS- -PMMA (e-f) (PFS = poly(ferrocenylethylmethylsilane) in (a)-(c) and the dimethyl analog in (d)-(f). ((a)-(c) Reprinted with permission from D.A Rider, K.A. Cavicchi, K.N. Power-Billard et al, Diblock copolymers with amorphous atactic polyferrocenylsilane blocks Synthesis, characterization, and self-assembly of polystyrene-block-poly(ferrocenylethylmethylsilane) in the bulk state, Macromolecules, 38, 6931, 2005. 2005 American Chemical Society, (d) Reprinted with permission from C. Kloninger and M. Rehahn, Bicontinuous gyroidic morphologies in ferrocenyldi-methylsilane-b-methyl methacrylate diblock copolymer blends, Macromolecules, 37, 8319, 2004. 2004 American Chemical Society, (e)-(f) Reproduced with permission from U. Datta and M. Rehahn, Synthesis and self-assembly of styrene-[l]dimethylsilaferrocenophane-methyl methacrylate penta-block copolymers, Molecular Rapid Communications, 2004,25,1615. Wiley-VCH Verlag GmbH Co. KGaA.)...

Bates F. S., Fredrickson G. H., Hucul D., and Hahn S. F. (2001) PCHE-based penta-block copolymers Evolution of a new plastic. AIChE J. 47 762-765. 

Abandansari, H., Aghaghafari, E., Nabid, M., Niknejad, H. Preparation of injectable and thermoresponsive hydrogel based on penta-block copolymer with improved sol stability and mechanical properties. Polymer 54(4), 1329-1340 (2013)... 

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