Brush structure

Douglas JF, Kent MS, Satija SK, Karim A (2001) Polymer Brushes Structure and Dynamics. In Buschow KHJ (ed) Encyclopedia of Materials Science and Technology. Elsevier, Amsterdam Alexander S (1977) J Phys France 38 983 Halperin A, TirreU M, Lodge TP (1991) Adv Polym Sci 100 31 Singh C, Picket GT, Balazs AC (1996) Macromolecules 29 7559 Currie EPK, Norde W, Cohen Stuart MA (2003) Adv Colloid Inter Sci 100-102 205 Meredith JC, Karim A, Amis EJ (2002) MRS Bull 27 330... 

Diblock copolymer brush structure Thickness Thickness of tethered of outer block (nm) block (nm) Polymerization technique Refs. 

Fig. 10 Schematic PE brush structure. In a we show the weakly charged limit where the counterion cloud has a thickness d larger than the thickness of the brush layer, h. In b we show the opposite case of the strongly charged limit, where all counterions are contained inside the brush and a single length scale d h exists...

Clearly, the repulsion between the adsorbed PEO chains is significant which forces them to adopt strongly stretched conformations, a brush structure. The degree of... 

Figure 5-7. Bottle brush structure of a proteoglycan with a magnified segment.

The hydrolysis/elimination reaction of the f-butyl methacrylate brushes is not easily driven to full conversion. Whereas linear f-butyl methacrylate chains are fully converted to polyacrylic acid in dioxane with catalytic amounts of toluene sulfonic acid the cylindrical brush structures precipitated at about 50% conversion (sample PMA-PBMA31-MAS50). Complete cleavage of the ester groups was achieved, however, by dissolving the partial-... 

Figure 3 Examples of regimes found in range II (medium values of a), (a) regime dominated by purely two-dimensional overlap (of the hydrophobic coils here). Within this regime, there is no increase of the thickness of the hydrophobic layer when the surface concentration increases, with y = 3 the coils are in the excluded volume geometry. (b) regime dominated by a partial three-dimensional growth of the hydrophilic coils which form quasi-brush structures. In this regime, the contribution of the hydrophobic coils is independent of the surface concentration because they form a quasi-homogeneous layer, the value of y being 1, whatever the quality of the solvent...

Recently, we explored strategies for binding spiropyran moieties to structured brushes grafted from ETFE and Teflon (PTFE) surfaces in order to obtain light-sensitive structured polymer surfaces [18]. We focused on post-polymerization modification of grafted brush structures because this strategy increases the flexibility with respect to the optimization of the concentration of spiropyran moieties in the brushes. Moreover, the tedious synthesis and purification steps of spiropyran—monomer conjugates are circumvented. 

These examples demonstrate how enzymatic activity can be locally introduced on smfaces using polymer brush structures and how their activity is influenced by both chemical functionality and thickness of the brushes. 

Duebner M, Spencer ND, Padeste C. Light-responsive polymer surfaces via postpolymerization modification of grafted polymer-brush structures. Langmuir 2014 30(49) ... 

The difficulty of interpreting SEM images is illustrated in Figure 5.11. A P4VP brush structure was grafted from ETFE... 

PANI/NaFe Pj2 whisker and PANI/NaFe P nanowire composite were prepared by an in-situ compoxmding method [23]. From the TEM images of the composite particles (Figure 6.13), it is found that PANI grew perpendicularly to the surface of NaFe P skutterudite and formed a unique brush structure. Infrared spectra and thermal gravity analyses indicated that there should be a coordinate linkage between one end of PANI liner molecule and the surface of NaFe P, whisker or nanowire. The... 

Block-Type Brushes by Sequential Polymerization The sequential hving polymerization of two macromonomers or a macromonomer with a conventional comonomer forms either block-block- or block-coil-type brush structures. For example, giant rod-coil amphiphilic block copolymer bmshes were prepared via a stepwise metallocene-catalyzed polymerization [58]. In the first step, a concentrated solution of methacryloyl end-functionalized PS macromonomer (DP = 18.3, MWD = 1.05) was polymerized by the organosamarium(iii) catalyst in THF. After PS macromonomer was completely consumed, the active center remained living, and tert-butyl methacrylate tert-butyl methacrylate (tBMA) as a comonomer was added to grow the second block. After termination by ethanol, the poly(tert-butyl methacrylate) (PtBMA) coil block was hydrolyzed into a hydrophihc block, poly(methacrylic acid) (PMAA). The final product consisted of a hydrophobic PS brush block and a hydrophihc PMAA coil. The hydrophilic PMAA coil collapsed in nonpolar solvents, which forced the block-coil CPBs to self-assembled into giant micelles with PMAA as the core component and the stiff PS brush block as the shell to stabihze the micelles. 

Recently, surface modification techniques for polymer chains have progressed a great deal with the development of a new polymer synthesis method. In particular, surface-initiated atom transfer radical polymerization (SI-ATRP) is one of the most effective modification methods for preparing a well-defined dense polymer brush structure, or polymer brush, on solid substrates. Thus, a self-oscillating polymer brush prepared by SI-ATRP can be expected to create a novel self-oscillating surface with autonomous function, which will lead to potential applications in transporting systems for nanomaterials of flow control in microfluidics. 

---