Poly branched structure

Branched poly(ethyleneimine) is usually obtained by ring opening polymerization of ethyleneimine with cationic initiators. The various aspects of this reaction have been reviewed elsewhere 7). This is the origin of commercial PEI. For this kind of PEI, it has been definitely established that the molecular structure is highly branched, independently of the modalities of preparation. As a result, there are three types of functional groups, i.e. primary, secondary and tertiary amino groups. For instance,... 

Fig. 1 and Fig. 2 show the CP MAS NMR spectra of thus obtained poly(methylchlorosilane-co-styrene). The Si NMR spectrum indicates a predominating share of branched Si structures (resonance at -65 ppm) beside -SiCl2CH3 and -SiCH3Cl groups (37 and 15-30 ppm, respectively). In the C NMR spectrum the signals of polystyrene blocks (128 ppm, 146 ppm and spinning side bands, ethylene groups... 

The self-condensing copper-catalyzed polymerization of macromonomer of poly(tBA) with a reactive C—Br bond (H-6) affords hyperbranched or highly branched poly(tBA).447 Copolymerization of H-1 and TV-cyclohexylmaleimide induced alternating and self-condensing vinyl polymerization.448 The residual C—Cl bond was further employed for the copper-catalyzed radical homopolymerization of styrene to give star polymers with hyperbranched structures. Hyperbranched polymers of H-1 further serve as a complex multifunctionalized macroinitiator for the copper-catalyzed polymerization of a functional monomer with polar chromophores to yield possible second-order nonlinear optical materials.325... 

Fig. 6 Chemical structures of branched copolymers (x and y denote number averages of repeating units) a polyallylamine-gra/t-poly( /-methyl L-glutamate) (PAAx-g-PMLGluy, X = 175, y = 14), b poly(ethylene oxide)- Zoc/c-(branched-poly(ethylene imine)-gra/t-poly(y-benzyl L-glutamate)) (PEOx- -PEIy-g-PBLGlu2(o.4j+i) x = 113, y = 233, z = 0.2-2.9), and c poly(ethylene oxide)-MocA -([G-3]-dendritic poly(L-lysine)-acetal) (PEOx- -[G-3]-PALLys, x = 113, 227)...

Scheme 16 Schematic representation of novel hyperbranched glycostructures illustrating regularly interspaced ligands onto poly(ethyleneimine) backbone (75), comb-branch (GO) structure (76), interspaced spheroidal dendrimer (77), rod-shaped, cylindrical polymer with dendritic branch (78), and dendrigraft (79).

Poly(ethyleneimine) (PEI) is a representative polybase with either a linear or a branched polymer structure the former is more often abbreviated as LPEI and the latter as BPEI. The acid hydrolysis of poly(ethyloxazoline)... 

Silicone Resins. Silicone resins ate an unusual class of oiganosiloxane polymers. Unlike linear poly(siloxanes), the typical silicone resin has a highly branched molecular structure. The most unique, and perhaps most useful, characteristics of these materials ate their solubility in oiganic solvents and apparent miscibility in other polymers, including silicones. The incongruity between solubility and three-dimensional structure is caused by low molecular weight (Mn < 10, 000 g/mol) and broad polydispersivity of most silicotic resins. 

Topchieva. I.N. Kalashnikov, Ph.A. Mel nikov, A.B. Polushina, G.E. Lezov. A.V. Self-assembly of dendritic micellar structures based on triton X-100 and branched poly (ethylene oxide)-containing cyclodextrin s. Colloid J. 2002. 64 (1). 106-111. 

L. Antonietti, C. Aymonier, U. Schlotterbeck, V. M. Garamus, T. Maksimova, W. Richtering and S. Mecking, Core-shell-structured highly branched poly(ethylenimine amide)s synthesis and structure. Macromolecules, 38,5914-5920 (2005). 

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