Polymers dendrimeric

Way JL, Petrikovics I, Jiang J et al. (2001) Application of dendrimeric polymers as a drag carrier in pharmacology. Abstracts of Papers, 221st ACS National Meeting, San Diego, CA, United States, April 1-5, 2001 IEC-316... 

AN EMPIRICAL AND MODELING STUDY OF BORON SPECIATION IN SOLUTION WITH A REACTIVE DENDRIMERIC POLYMER... 

The cationic polymerization method of Cl3P=NSiMe3 has many new applications. The preparation of dendrimeric polymers with star-type architecture illustrates the versatility of this method (Fig. 3.29) [21]. 

Percec V, Kawasumi M (1992) Synthesis and characterization of a thermotropic nematic liquid crystalline dendrimeric polymer. Macromolecules 25 3843-3850 Percec V, Chu P, Ungar G, Zhou J (1995) Rational design of the first nonspherical dendrimer which displays calamitic nematic and smectic thermotropic liquid crystalline phases. J Am Chem Soc 117 11441-11454... 

Figure 6. Synthesis of the second generation dendritic wedges, 7d, with an isocyanate function at the focal point (top) and its reaction with polymer la to furnish the dendrimerized polymer 8 (bottom).

Combinatorial approach to unsymmetrically tiered macromolecules [214] is a brand new area of research which would allow dendrimerization of materials (e. g., glass, classical polymers, fibers) and thus enable fine tuning of macromole-cular properties. For example, treatment of an amine terminated dendrimer with a mixture of complementary, isocyanate-based monomers [215, 216] affords a heterogeneous surfaced dendrimer. Selective transformation of the surface nitrile moieties via metal-catalyzed reduction to obtain a new polyamine dendrimer allows further combinatorial-based elaboration as illustrated in Fig. 42. 

Tomalia, D. A. and Majoros, I. Chapter 9, Dendrimeric Supramolecular and supra-macromolecular Assemblies in Supramolecular Polymers (A. Ciferri, ed.), Marcel Deker, New York, 359-434 (2000). 

The expected contribution of catalysis in this area will derive both from the availability, at low processing costs, of new monomers obtained from biomasses and from the development of an optimized combination of biotechnology processes with classical and new biocatalytic processes. Research priorities for catalysis in the area of polymers from renewable materials for packaging, furniture, domestic water purification and recycling include the need to develop novel catalysts, e.g., for functionalization of polymeric and dendrimeric materials, with side-chain photoactive molecular switches (to be used as smart materials), or the development of multifunctional materials, combining, for example, nanofiltration with catalytic reactivity. 

The thermal behavior of the hyperbranched polymer 7, as well as that of the related tetra- and octanuclear dendrimers 1 and 2, was examined by thermal gravimetric analysis (TGA) and derivative thermogravimetry (DTG). The samples were heated at a ramp rate of 10 °Cymin under nitrogen atmosphere in the tenqierature range 25-8(K) °C. The major decompositions occur between 340 and 540 °C for the tetranuclear 1, and between 370 and 520 °C for the octanuclear 2, whereas for polymer 7 a faster rate of weight loss is observed at a higher (480 and 560 C) temperature range. The thermal stability of the network dendrimeric material 7 is... 

In view of the environmental issues and operational simplicity, heterogeneous catalytic systems have been suggested to be advantageous. Gibson and co-workers first introduced polymer-bound cobalts 27 and 28 to this end." Subsequently, Portnoy and Dahan immobilized cobalt on dendrimeric phosphane ligands, which have a partial structure of 29 (Figure 6)." ... 

We have synthesized and tested an example boron-chelating polymer based on a commercially available dendrimeric poly(amido amine) (PAMAM). Dendrimeric chelants offer several advantages over polymers typically used in PAUF. Foremost among these is the reduced viscosity of dendrimer solutions as compared to solutions of linear polymers[6]. This allows the use of higher polymer concentrations than previously feasible (though in the present study we worked at polymer concentrations of less than 5% due to the expense of the starting dendrimer). In this study, the dendrimeric chelant also serves as a convenient, monodisperse polymer with which to test the mathematical model for boron speciation which is derived from the work of Wise and Weber[l],... 

CoCp unit C-C bond activation, 7, 80 CoCp unit CH activation, 7, 79 in ethylene polymerization, 7, 81 substituted ligands, 7, 71 synthetic applications, 7, 74 with )4-cyclobutadiene applications, 7, 66 new ligand preparation, 7, 70 with )4-(cyclobutadiene) ligands, 7, 59 dendrimeric cobaltocenium derivatives, 7, 88 with fullerenes, 7, 51 HP-NMR and HP-IR studies, 1, 488 with rj -hydrocarbyl units, 7, 8 immobilized, as polymer support, 12, 681 kinetic studies, 1, 520 with )3-ligands, 7, 56 with metallaboranes, 3, 158 overview, 7, 1-119... 

Functionalized polymers with comb-like, rotaxanic-, and dendrimeric structures [H. Ritter, GITFachz. Lab. 1994, 38(6), 615-619]. 

The amino alcohol-dialkylzinc system can be applied to ehiral amine synthesis. Polymer-supported ephedrine was found to be an effective chiral ligand in the reaction of N-diphenylphosphinoylimines with diethylzinc (Eq. 19) [77-79]. The polymeric catalysts were, however, less efficient than monomeric model reactions. Several dendrimeric chiral ligands containing the ephedrine moiety (60, 61) have also been synthesized and used in the asymmetric alkylation of 7 -diphenylphosphinylimines by diethylzinc [80]. Both yield and enantioselectivity of the reaction were, however, lower when the dendrimeric ligands were used. 

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