Sugar based polymers polymer

Fig. 1.14 (A) Single-wall carbon nanotubes wrapped by glyco-conjugate polymer with bioactive sugars. (B) Modification of carboxyl-functionalized single-walled carbon nanotubes with biocompatible, water-soluble phosphorylcholine and sugar-based polymers. (A) adapted from [195] with permission from Elsevier, and (B) from [35] reproduced by permission of Wiley-VCH.

Within the framework of systematic research to explore the potential of sugar-based polymers, Muiioz-Guerra and Galbis et al. [24-31] have employed various... 

From the results presented in this chapter we can conclude that it is feasible to prepare sugar-based polymers analogous to the more qualified technological polymers - polyamides, polyesters, polyurethanes - with an enhanced hydrophilicity and degradability. However, in most cases, the high costs associated with the preparation of the monomers restrict the application of these polymers to biomedical applications and other specialized fields. More readily available monomers and simpler polymerization processes have to be found if sugar-derived polymers should compete with petrochemical-based polymers that are used in domestic applications. 

The era of biomimetic peptide- and sugar-based polymer vesicles has just begun and seems very promising. Bioinspired vesicles are mainly applied for drug deliv-ery/release and the fabrication of composite materials, but could readily be used for biomimetic materials science, biomineralization, and so on. Especially interesting are smart vesicles changing properties in response to an external stimulus (temperature, pH, ions). 

An entirely different approach to sugar-based polymers involves the use of selective enzymatic catalysts to prepare vinyl sugar monomers that are subsequently polymerized via chemical catalysts. Tokiwa and Kitagawa (25) published extensively on this subject, and their contribution within this book describes a wide range of sugar monomer structures. 

Sugar Based Polymers Overviews and Recent Advances of Vinyl Sugars... 

Sugar based polymers, which are obtained by polymerization of vinyl sugars, have recently received increased attention from two viewpoints. One is the development of environmentally friendly material from renewable resources. Another is physiologically active material that mimics carbohydrate on cell surface. This article provides an overview of known sugar based polymers and the recent advances of the poly(vinylalcohol) (PVA) with sugar pendants. 

Recently, the development of new functional materials from renewable resources such as various kinds of saccharides has received remarkable interest 1, 2, 3). Various types of synthetic polymer containing saccharides have been investigated ( , 5). There are two types of sugar-based polymers (i) sugar-containing linear polymer (ii) polymer with sugar pendant (Figure 1). 

Poly (Vinylalcohol sugar ester) Figure 10. Strategy for PVA type sugar based polymer... 

Feng, X., East, A.J., Hammond, W.B. et al. (2011) Overview of advances in sugar-based polymers. 

Chapter 8 is a review of the use of polysaccharides, perhaps some of the oldest and most well-known ingredients used in personal care. Because polysaccharides are derived from natural sources, the nature of the monosaccharides that comprise these sugar-based polymers and how nature designs the polysaccharides are addressed first. This discussion is followed by greater details of individual cosmetically important polysaccharides based primarily on the ionic nature of the polysaccharide, that is, anionic, cationic, nonionic, or amphoteric, which can be either naturally developed by the polysaccharide source or manipulated by human intervention and invention. The effects of hydrophobic modification of polysaccharides are also discussed. The chapter concludes with a brief discussion of certain polysaccharides that appear to have physiological effects on the human body when applied topically. 

The complexation of DNA and polycations is a function of the intrinsic properties of the two components. For instance, from the use of synthetic polycations for complexing DNA also arises the problem of polydispersity of polymers (a polymer sample is usually composed of macromolecular species of differing molar masses) compared with DNA, which is monodisperse. Because the polydispersity of the polycation could be an issue in studies of IPECs, sugar-based polymers (usually polydisperse except if fractionated), conjugated polymers (polydispersity, Mw/Mn > 2), branched PEI derivatives, and hyperbranched polymers are out of the scope of this review, as already mentioned. Only polymers synthesized via controlled or living polymerization methods will be discussed [55-57]. 

Figure 22.18 The left drawing shows the sugar-phosphate chain in DNA. The right drawing shows how DNA is a nucleotide (phosphate-sugar-base) polymer. 

Two of the main European collaborations Tharwat has had in recent years have been the groups of Dotchi Exerowa in Sofia and that of Conxita Solans in Barcelona. With Dotchi the work has focused on foam and emulsion films and with Coxita (plus Paul Luckham) on the stabilization of latex particles. Indeed in much of this latter work on foams, emulsions, and particle dispersions, very efficient stabilizers, based on hydrophobically-modified, sugar-based polymers, have been studied. It was observed, for example, that, when these are added, polymer latex dispersions are stable in Na2S04 solutions of up to 1.5 mol dm . ... 

It should be pointed out that the raw materials for VAM and its related polymers (i.e. ethylene and acetic acid) are produced from fossil resources, mainly crude oil. It is possible to completely substitute the feedstock for these raw materials and switch to ethanol, which can be produced from renewable resources like sugar cane, com, or preferably straw and other non-food parts of plants. Having that in mind, the whole production of PVAc, that nowadays is based on traditional fossil resources, could be switched to a renewable, sustainable and C02-neutral production process based on bioethanol, as shown in Fig. 3. If the vinyl acetate circle can be closed by the important steps of biodegradation or hydrolysis and biodegradation of vinyl ester-based polymers back to carbon dioxide, then a tmly sustainable material circle can be established. 

Synthetic polymers obtained from sugar-based monomers are innocuous for human health. Their hydrophilic nature ensures a greater hydrolytic degradability [6], and reduces their environmental impact compared to classic polymers [3]. 

Some reviews have been published on the synthetic carbohydrate-based polymers and glycopolymers [11-15]. However, they refer mainly to poly(vinylsaccharide)s and other conventional functionalized polymers having sugars as groups pendant from the main chain of the polymer. In this chapter we shall describe those sugar-based monomers which lead to polymers having the sugar units incorporated into... 

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