PCEMA

Liu et al. prepared palladium nanoparticles in water-dispersible poly(acrylic acid) (PAA)-lined channels of diblock copolymer microspheres [47]. The diblock microspheres (mean diameter 0.5 pm) were prepared using an oil-in-water emulsion process. The diblock used was poly(t-butylacrylate)-Wock-poly(2-cinna-moyloxyethyl) methacrylate (PtBA-b-PCEMA). Synthesis of the nanoparticles inside the PAA-lined channels of the microspheres was achieved using hydrazine for the reduction of PdCl2, and the nanoparticle formation was confirmed from TEM analysis and electron diffraction study (Fig. 9.1). The Pd-loaded microspheres catalyzed the hydrogenation of methylacrylate to methyl-propionate. The catalytic reactions were carried out in methanol as solvent under dihydro-... 

Fig. 9.1 Transmission electron microscopy images of Pd-loaded PCEMA-fo-PAA microspheres containing 27% Pd (left) and 63% Pd (right). (Adapted from [47])...

PtBA-b-PCEMA poly(t-butyl acrylate)-block-poly(2-cinnamoyloxyethyl) methacrylate... 

Liu and coworkers systematically used photo-cross-linking to stabilize micelles containing a PCEMA core [82]. The micellar characteristic features (Z, etc.) were not affected by the cross-linking process, as proven by SLS, DLS, TEM, and SEC. 

Liu and coworkers have investigated PI-PCEMA-PtBA triblock copolymers in which the central PCEMA block was cross-linked by UV irradi-... 

Fig. 3 Structure of PtBA-PCEMA and TEM image after hydrolysis. Reproduced from [20]... 

Results from TEM experiments on solutions of a series of poly(styrene)-poly(cinnamoylethyl methacrylate) (PS-PCEMA) diblocks with short PS blocks and long PCEMA blocks have been compared (Tao et al. 1997) to the theories for block copolymer micelles described above. Micelles of type IV in the Zhulina-Birshtein classification (Fig. 3.18) formed in cyclopentane, which is a selective solvent for PCEMA (coronal A block), when the ratio of was... 

PDPAEMA poly(N,N-diisopropylaminoethyl methacrylate) PCEMA poly(cinnamoylethyl methacrylate)... 

The negative sign of K in polymer solutions of PCEMA, PNOBS and PPhEAA means that the side groups of these comb-like polymers are oriented in the electric field with their long axes normal to the field (in contrast to the corresponding monomer molecules) and, hence, this orientation is not free (as for polystyrene) but is in correlation with that of the main chain. 

This conclusion is supported by the existence of low frequency dispersion of EB in solutions ofthesepolymers (Fig. For all PCEMA fractions studied in the frequency range 0.5 to... 

Relative EB An /Ano as a function of the frequency of the electric field V for PCEMA fractions in tetrachloro-methane with different molecular weights M 63, 234). 10-6 = 19.1 (1) ... 

The formation of cylindrical domains of one block in a matrix of another, in diblock copolymers, has also been exploited for the generation of nanochannels in thin film membranes [40, 41]. Using diblock copolymers of PtBA-b-PCEMA, but this time with a larger volume fraction (ca. 74 vol%) of the photo-crosslinkable PCEMA block, Liu et al, prepared thin polymer films containing a densely packed array of nanocylinders (diameter 22 nm) [40]. As expected, in these cases the PCEMA block forms the continuous phase with nanocylinders of the hydrolyzable PtBA blocks forming a densely packed array. Typically, thick films (or disks of ca. 

Fig. 1S.9. TEM image of a small area of 50 nm thick PAA-h-PCEMA film generated by crosslinking the PCEMA matrix followed by hydrolysis of the PtBA domain. (Reprinted with permission from Macromolecules, 1997, 30, 1851. 1997 American Chemical Society [40].)...

---