Hybrid graft copolymers

Yang, J., Wu, K., Konak, C., and Kopecek, J. "Dynamic light scattering study of self-assembly of HPMA hybrid graft copolymers". Biomacromolecules 9(2), 510-517 (2008). 

Hybrid graft copolymers having silicon-based polymer backbones were also prepared by the metal-mediated radical polymerizations of styrene. The phenyl groups of poly[(methylphenyl)silylene] were bromomethylated and then employed as the grafting points of polystyrene (G-16).294,441 Polysiloxane can be employed also as a backbone (G-17) by introduction of benzyl chloride units into the pendant vinyl-functionalized poly(dimethylsiloxane).409... 

Hybrid Graft Copolymers. The most widespread complex hybrid structures are the graft copolymers. Generally, all typical grafting techniques have been applied for the preparation of synthetic polymer/PLL hybrid graft copolymers. 

On the whole, the miniemulsion polymerization process proved to be effective for incorporating an alkyd resin into acrylic coated copolymers. The reaction produced stable, small particle size latexes that contain graft copolymer of the acrylic and alkyd components. Attempts at macroemulsion hybrid polymerization were unsuccessful. 

Anionic polymerization of functionalized cyclotrisiloxanes is a good method for the synthesis of well-defined functionalized polysiloxane with control of molecular mass, polydispersion, and density and arrangement of functional groups. These polymers may serve as reactive blocks for the building of macromolecular architectures, such as all-siloxane and organic-siloxane block and graft copolymers, star-, comb- and dendritic-branched copolymers and various polysiloxane-inorganic solid hybrids. 

Several approaches used to prepare hybrid polymers in which polyacetylene is an electroactive component are presented. Specifically, these involve the preparation of (1) composites by in-situ polymerization, (2) graft copolymers utilizing carbanions in n-type (CH)X as polymerization initiators, and (3) A-B diblock copolymers exploiting anionic-to-Ziegler-Natta transformation reactions. 

In the area of novel materials CMU protected (co)polymers prepared by ATRP except with CCI4 initiator and telechelic polymers prepared by CRP with MW > 20,000 (49) copolymers with a tme gradient segment (30) polar ABA block copolymers, (30) and well defined graft copolymers and segmented copolymers with one or more CRP blocks where the macroinitiator had been prepared by another polymerization process. (36) In addition, the use of tethered initiators allowed synthesis of hybrid core/shell copolymers. Pending applications disclose other novel polymeric materials. 

Numerous polymers and copolymers have been synthesized using NMP techniques. See, for example, the reviews by Hawker [58, 59]. Graft copolymers and hybrid materials synthesized by NMP are reviewed in Chapter 10. 

Fig. 1. Hybrid organic-inorganic polymer systems can be devised for all structural paradigms of polymer chemistry including (a) homopolymer, (b) block copolymer, (c) copolymer, (d) graft copolymer, and (e) interpenetrating polymer networks, including, shown as geometrical abstractions, (f) true and (g) semi-interpenetrating versions, where crosslinks are depicted as junctions of horizontal and vertical lines.

In this section, some peculiarities of copolymerization conducted in CRP systems will initially be discussed and then examples of various types of copolymers will be provided. They will include statistical, gradient, and alternating copolymers, as well as block and graft copolymers. Some special systems will be also presented and they will include preparation of stereoblock copolymers, and various hybrid materials formed by either mechanistic transformation or by growing well-defined polymers from flat, colloidal, or irregular surfaces. 

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