Polystyrene-polyisoprene diblock copolymers

Figure 13.15 Reduced storage modulus versus reduced frequency arco for a lamellae-forming polystyrene-polyisoprene diblock copolymer (M = 22,000) at temperatures above the order-disorder transition temperature Todt = 152°C, and quenched to temperatures below it. The disordered samples show terminal behavior, and the ordered (but unoriented) ones show nonterminal behavior. (Reprinted with permission from Patel et al.. Macromolecules 28 4313. Copyright 1995, American Chemical...

Figure 13.22 Damping functions hf y) and hs y) for the fast and slow relaxation processes of a 15 wt% solution of a micelle-forming polystyrene-polyisoprene diblock copolymer (molecular weights, respectively, of 14,000 and 29,000) in a low-molecular-weight (A/ = 4,000) polyisoprene. Damping functions for linear and star polymers and for silica dispersion are shown for comparison. (From Watanabe et al. 1997, with permission from Macromolecules 30 5905. Copyright 1997, American Chemical Society.)...

Kesselman, E., Talmon, Y., Bang, J. et al. (2005) Cryogenic transmission electron microscopy imaging of vesicles formed by a polystyrene-polyisoprene diblock copolymer. Macromolecules, 38 (16), 6779-6781. 

Polymer (B) polystyrene-b-polyisoprene diblock copolymer 1997ZHA... 

Fig. 15. Pulsed ELDOR (DEER) distance measurements on the ionic spin-probe TEMPO-4-carboxylate attached to ionic clusters in ionically modified diblock copolymers, (a) Schematic structure of a monoionic polystyiene-polyisoprene diblock copolymer modified by sulfonate end groups on the polyisoprene bloek (sample series S). (b) Schematic structure of an a,0)-zwitterionic polystyrene- ly-isoprene diblock copolymer modified by a quaternary ammonium end group on the polystyrene block and a sulfonate end group on the polyisoprene block (sample series Z). (c) Schematic structures of the polymer chains. Tlie solid line corresponds to the harder block polystyrene, the dotted line to the softer block polyisoprene. (d) Dependence of ionic cluster size (ri) and intercluster distance (r2> on molecular weight. Squares correspond to sample series Z, circles to sample series S, and diamonds to monionic homopolymers (polystyrene modified with quaternary ammonium end groups). The dotted and dashed lines are fits of a constant function. The solid line is the best-fit scaling law r2 = 2.09...

Lee W, Cho D, Chang T, Hanley KJ, Lodge TP. Characterization of polystyrene-b-polyisoprene diblock copolymers by liquid chromatography at the chromatographic critical condition. Macromol 2001 34 2353. 

Mass V, Bellas V, Pasch H. Two-dimensional chromatography of complex polymers, 7. Detailed study of polystyrene—block-polyisoprene diblock copolymers prepared by sequential anionic polymerization and coupling chemistry. Macromol Chem Phys 2008 209 2026-39. 

Hasegawa, H., Tanaka, H., Yamasaki, K., andHashimoto, T. (1987) Bicontinuous microdomain morphology of block copolymers. 1. Tetrapod-network strucmre of polystyrene-polyisoprene diblock polymers. Macromolecules, 20,1651-1662. 

Sakurai S, Me H, Umeda H, Nomura S, Lee HH, Kim JK. Gyroid structures and morphological control in binary blends of polystyrene-block-polyisoprene diblock copolymers. Macromolecules 1998 31 336-43. 

Polystyrene-block-Polyisoprene (SI Diblock) Copolymer or Polyisoprene-block-Polystyrene (IS Diblock) Copolymer... 

Polystyrene-b-polyisoprene diblock copolymer (hydrogenated PIP) N,N-dimethylformamide and methylcyclohexane 93P01... 

Fig. 8. Effect of varying composition on the ordered-phase symmetry in polystyrene-polyisoprene (PS-PI) diblock copolymers [92]...

LeiblerL., Theory of microphase separation in block copolymers. Macromolecules, 13, 1602, 1980. Eoerster S., Khandpur A.K., Zhao J., Bates E.S., Hamley I.W., Ryan A.J., and Bras W. Complex phase behavior of polyisoprene-polystyrene diblock copolymers near the order-disorder transition. Macromolecules, 21, 6922, 1994. 

The purpose of this contribution is to show how the design of a new dianionic species can lead to interesting advances in block copolymerization and especially to original PA(P0)2 starshaped block copolymers. PA is a hydrophobic block polystyrene, polytertiarybutylstyrene (PTBS) or polyisoprene (Pi). The surface activity of this novel and well mastered molecular architecture is considered and compared as far as possible with the behavior of the corresponding PA-PO diblock copolymers. 

We have studied three different lamellar polystyrene-Wock-polyisoprene (SI) diblock copolymers (see Table 1) with molecular weights of around 50 kg/mol using... 

The substantial work on polystyrene/polybutadiene and polystyrene/ polyisoprene blends and diblock and triblock copolymer systems has lead to a general understanding of the nature of phase separation in regular block copolymer systems (5,6). The additional complexities of multiblocks with variable block length as well as possible hard- and/or soft-phase crystallinity makes the morphological characterization of polyurethane systems a challenge. 

Khandpur AK, Forster S et al (1995) Polyisoprene-polystyrene diblock copolymer phase diagram near the order-disorder transition. Macromolecules 28 8796-8806... 

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