Poly -WocA:-polystyren

Table 2 contains examples of common or semi-systematic names of copolymers. The systematic names of comonomers may 2ilso be used thus, the polyacrylonitrile-WocAr-polybutadiene-WocA -polystyrene polymer in Table 2 may also be named poly(prop-2-enenitrile)-WocAr-polybuta-l,3-diene-fofocA -poly(ethenylbenzene). lUPAC does not require alphabetized names of comonomers within a polymer name many names are thus possible for some copolymers. 

The crystalline homopolymers spatially confined in nanocylinders can be prepared using the microphase separation of block copolymers, followed by the photocleavage of block junctions (Fig. 10.4), where o-nitrobenzyl (ONB) groups inserted between different blocks are conveniently used for the photocleavage reaetion [48]. Nojima et al. [44—47] synthesized poly(e-eaprolaetone)-WocA -polystyrene (PCL-ft-PS) diblock copolymers with ONB between PCL and... 

Poly(styrene)-6/ocl -(hydrogenated polybutadiene)-WocA -polystyrene ... 

FIGURE 11.1 TEM images of (a) cotton-derived CNs from dilute water suspension and (b) CNs coated with the triblock copolymer of xyloglucan oligosaccharide-WocA -poly(ethylene glycol)-i>/oc -polystyrene (XGO-fc-PEG-l -PS) (c) from dilute toluene suspension (scale bar 1 im). Reprinted with permission from Ref. [15]. 

Prochazka et al. [31] studied solvent relaxatitm in the shells of polystyrene-WocA -poly(ethylene oxide) (PS-PEO), polystyrene-Woc)t-poly(2-vinylpyridine) (PS-PVP), and polystyrene-Woc)t-poly(2-vinylpyridine)-Woc)t-poly(ethylene oxide) (PS-PVP-PEO) in aqueous solutions, using Patman as a fluorescent probe. While in the case of the PEO shell of the PS-PEO micelle, a slow relaxation was observed because the mobility of water molecules in the shell was hindered by the strong hydrogen bonding to PEO chains, the solvent cage of the probe in the shell of PS-PVP micelles appeared to relax much faster. Interestingly, water in PS-PVP-PEO terpolymer micelles exhibited a slow relaxation as in the case of the PS-PEO diblock, but the relaxation time became pH responsive due to the presence of the weak polyelectrolyte PVP block. 

In principle, a determination of the mass allows for a measurement of the unique composition of block copolymers. It has been possible to determine the molecular weights and molecular weight distributions of both components of a block copolymer of polystyrene-WocA -poly(a-methylstyrene) by using MALDI-TOF [58]. The MALDI/TOF mass spectrum of a block copolymer sample containing 69% styrene and 31% a-methylstyrene is shown in Fig. 10.15. 

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