Renewable polymer polymers

Keywords. Monomers from renewable resources, Polymers from renewable resources, 1,3-Propanediol, Succinic acid, Lactones, Cyclohexanedimethanol, Polyethyleneglycol, Chain-extension, Poly(ester-urethane)s, Poly(ester-carbonate)s... 

Biosynthetic Sources for Monomers with a Potential for Making Novel Renewable Polymers... 

Catalytic reduction and/or fermentation to produce 1,3-propanediol, a polymer with applications in the textile sector and a key feedstock for production of the renewable polymer Sorona produced by Du Pont... 

Langer R. 1998. Drug delivery and targeting. Nature 392 (Suppl.) 5-10. Leaversuch, R. 2002. Renewable PLA polymer gets green light for packaging uses. 

A miscible polymer—polymer blend almost always yields a physical- property spectrum superior to the individual components, and this allows the development of a new set of products with significant savings in capital investment. Partly for this reason and partly because new and commercially viable polymers are becoming harder to come by/ the plastic industry has expended a sizeable sum towards identifying miscible high-performance polymer mixtures. Indeed, the more recent renewed experimental and theoretical programs have resulted in an increased number of known miscible blends. On the commercial scene, however, successful miscible polymer-polymer blends are still rather few and are limited to... 

The reactivity of resorcinol with formaldehyde is essential for developing the cohesive strength of the interlayer and its bonding characteristics. Condensed tannins are known to be very reactive with formaldehyde (7-0), so these renewable phenolic polymers are good candidates as resorcinol replacements. Indeed, condensed tannins from wattle and pine bark extracts have been successfully used in cold-setting, wood-laminating adhesives, and the former are used extensively in the commercial production of laminated timbers in South Africa (Pizzi, A., National Timber Research Institute, Pretoria, South Africa, personal communication, 1982) (10-13). 

This chapter deals with polymers synthesized from oilseed sources. However, to provide the reader with an appreciation of the area of renewable, biodegradable polymers and the place within this area that polymers from oil seeds occupy in terms of functionality, price, and acceptability, some other polymers from major renewable sources are also discussed. The most well-known and widely used renewable biodegradable polymers are those from polysaccharides. The principal polysaccharides of interest to polymer chemists are starches and cellulose, both of which are polymers of glucose. In addition to these, fibers, polylactic acid (PLA), and triacylglycerols of oils are of particular interest for the development of biodegradable industrial polymers. 

Even though some technologies for processing natural polymer materials have been established for centuries, it is clear that to date, only a very small fraction have been explored. As nature herself has shown, the potential for building different polymer-based materials is almost limitless, and properties and functions can far exceed those attainable with synthetic polymers. Hopefully over the next 50 years the need for green polymers will provide the impetus for the much greater research efforts that are needed to accelerate the man-made evolution of materials based on natural, renewable resource polymers. 

This chapter has revealed that the gum from. M.oleifera as a polymer has great potential for renewable polymer applications. However, so far, research in this area seems to be in its infancy stage. Research in the agronomical aspects of M.oleifera is beginning to grow, although more still needs to be done as evidenced by the limited literature in this area. The agronomical data of M.oleifera will not only assure the sustainability of the above applications, but... 

Cellulose and its derivatives - cellulose acetate - are renewed polymers, that, together with the whole complex of valuable and indispensable properties, defines continuous growth of their production. 

Balata tree, Mimusops Balata, have achieved economic importance or are considered as resources for natural mbber as a renewable polymer. Chemically, natural rubbers are polyterpenes consisting of 1,4-c -(mbber) or 1,4-frans-(gutta-percha, balata) polyisoprene, generated by enzymatically catalyzed biosynthetic polymerization of isoprene, and stabilized by phospholipids. 

Natural polymers, serving the sustainable development are of increasing importance in the next century. In spite of the extreme rapid development in the synthetic polymers, the yearly yield of the renewable natural polymers, the biomass — is still three order of magnitude higher (hundreds of billion tons/year ) than the production of plastics worldwide (200 Mt/a). 

The Avantium YXY Technology to Produce PEF, a Novel Renewable Polymer... 

Fig. 3 shows the molecular structure of PLA. PLA polymer is made up of many long chains consisting of the repeat unit shown in the figure. PLA is derived from renewable resources, such as corn starch via fermentation and it is biodegradable under the right conditions, such as the presence of oxygen (Tsuji et ah, 2010). Thus, PLA is a possible candidate of a new class of renewable polymers as a substitute for the petrochemical polymers. However, the physical properties of PLA are inadequate for the replacement of conventional commodity plastics in many applications. 

It is a linear polysaccharide composed of randomly distributed p-(l-4)-linked o-glucosamine (deacetylated unit) and V-acetyl-D-glucosamine (acetylated unit). It is made by treating shrimp and other crustacean shells such as crabs and krills with the alkali NaOH. Chitosan is a naturally abundant and renewable polymer and has excellent property such as biodegradability, biocompatibility, nontoxicity, and good adsorption [92]. The structure of chitosan is given in Figure 1.21. 

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