Chain end macromolecules

Pan Y, Ford WT. Amphiphilic dendrimers with both octyl and triethylenoxy methyl ether chain ends. Macromolecules 2000 33 3731-3738. 

N. Martinez-Castro, M.G. Lanzendorfer, A.H.E. Muller, J.C. Cho, M.H. Acar, and R. Faust, Polyisobutylene stars and polyisobutylene-block-poly(tert-butyl methacrylate) block copolymers by site transformation of thiophene end-capped polyisobutylene chain ends, Macromolecules, 36(19) 6985-6994, September 2003. 

Stereoregulation for different reactive chain ends. Macromolecules 1982, 15, 211-212. 

Zambelli, A. Sacchi, M. C. LocateUi, R Zaimoni, G Isotactic polymerization of a-olefins Stereoregulation for different reactive chain ends. Macromolecules 1982,15, 211-212. 

Shiono, T. Kurosawa, H. Ishida, O. Soga, K. Synthesis of polypropylenes functionalized with secondary amino groups at the chain ends. Macromolecules 1993, 26, 2085-2089. 

Misumi, Y Masuda, T. Living polymerization of phenylacetylene by novel rhodium catalysts. Quantitative initiation and introduction of functional groups at the initiating chain end. Macromolecules 1998, 31, 7572-7573. 

Chen, N., Maeda, N., Tirrell, M., and Israelachvili, J. (2005) Adhesion and friction of polymer surfaces the effect of chain ends. Macromolecules, 38,3491-3503. 

Druliner JD (1991) Living radical polymerization involving oxygen-centered species attached to propagating chain ends. Macromolecules 24(23) 6079-6082... 

G. Henn, D. J. Bucknall, M. Stamm, P. Vanhoorne, R. Jerome. Chain end effects and dewetting of thin polymer films. Macromolecules 29 4305 313, 1996. 

Hyperbranched polymers generally have very low melt and indinsic viscosities. The large number of chain-end functional groups present in hyperbranched macromolecules have also been shown to dramatically affect physical properties... 

Interest in anionic polymerizations arises in part from the reactivity of the living carbanionic sites4 7) Access can be provided to polymers with a functional chain end. Such species are difficult to obtain by other methods. Polycondensations yield ro-functional polymers but they provide neither accurate molecular weight control nor low polydispersity. Recently Kennedy51) developed the inifer technique which is based upon selective transfer to fit vinylic polymers obtained cationically with functions at chain end. Also some cationic ring-opening polymerizations52) without spontaneous termination can yield re-functional polymers upon induced deactivation. Anionic polymerization remains however the most versatile and widely used method to synthesize tailor made re-functional macromolecules. 

Tsui, O. K. C. and Zhang, H. F. (2001) Effects of chain ends and chain entanglement on the glass transition temperature of polymer thin films. Macromolecules, 34, 9139—9142. 

In an optimally controlled process free from transition-metal ions hydrogen peroxide bleaching is remarkably safe, there being no reported detrimental effects of bleaching at around 100 °C or for more than several hours [143]. Under such conditions, most of the peroxide appears to be consumed in the oxidation of chain end units of the cellulose macromolecule. The other major effect on the substrate is oxidation of secondary hydroxy to keto groups, accompanied by the formation of very few aldehyde or carboxyl groups [235]. 

The carbonium ion so produced then adds more monomer molecules and grows until there is abstraction of a proton from the growing chain end of the macromolecule and its recombination with conjugated... 

A second, and potentially more useful feature is the stability of these unimolecu-lar initiators to a wide variety of reaction and polymerization conditions which is in sharp contrast to traditional initiators for anionic procedures, such as n-butyl lithium. This allows the initiators to be fully characterized, purified and handled by normal techniques, thus simplifying the polymerization process. It also permits a variety of chemical transformations to be performed on the initiator prior to polymerization, which greatly facilitates the preparation of chain end functionalized macromolecules. For example, the chloromethyl functionalized al-koxyamine, 18, can be readily converted in high yield to the corresponding aminomethyl derivative, 19, followed by polymerization to give well-defined linear polymers, 20, with a single primary amine at the chain end (Scheme 12). 

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