Biopol

Hayward et al. 1994] Hayward, S., Kitao, A., Go, N. Harmonic and anharmonic aspects in the dynamics of BPTI A normal mode analysis and principal component analysis. Prot. Sci. 3 (1994) 936-943 [Head-Gordon and Brooks 1991] Head-Gordon, T., Brooks, C.L. Virtual rigid body dynamics. Biopol. 31 (1991) 77-100... 

Table 31.3 Some selected properties of polyhydroxybutyrate-valerate copolymers (Biopol—Zeneca)...

Although first marketed by Zeneca, a company split off from ICI in 1993, under the trade name of Biopol, marketing was transferred to Monsanto in May 1996. In 1993 production capacity was 600t.p.a. but prior to the Monsanto takeover had been expected to rise to 5000-10 000 t.p.a. by the late 1990s. However, in November 1998 Monsanto announced that it was discontinuing the Biopol programme. 

Tests by Gatenholm et al. [8,10] on PHB-HV copolymers containing cellulose fibers (for example, the tradenamed Biopol) show that the mechanical properties of these systems are determined by the fiber and the fiber matrix interface on the one hand, and on the other hand by the composition of the matrix, that is, of HV proportion in the matrix. At an increased proportion of HV, the stiffness of the composite is reduced up to 30%, whereas elongation at break increases until about 60%. 

Biomedical applications, 27 Bionolle, 28, 42, 43 Biopol polyesters, 28, 41 Bioresorbable polyesters, 27 synthesis of, 99-101 Biphenol-based copolymers, 356 Bis(aryloxy) monomers, polymerization of, 347... 

It is interesting to consider that biopol)nners are by no means new to this world. It is only because of our fascination with petrochemical products that these wonderful materials have been neglected for so long. In fact, natural or biopol3Tners have been considered in the 1940s and Henry Ford has used these biopol3maers in the construction of a car. However, with the discovery of petrochemical polymers, the low cost of these quickly over shadowed natural materials. 

The diverse field of biopol miers outlined in this book does underline its importance today. We can expect to see biopolymers in packaging, medicine, construction, in fact in almost every part of life - just as S)mthetic plastics are ubiquitous with everyday life at the moment. 

This class of polymer was first launched commercially by ICI in 1990 under the trade name Biopol. Despite high hopes for mass commercial production of this material it has so far largely failed as a commercial polymer. In 1996 the business was sold to Monsanto who later sold the business to Metabolix, who also had a small business producing PHAs. 

The flow-rate affects only solubility-limited extractions. Increasing the flow-rate has a similar effect to increasing pressure. Baner el al. [328] observed a marked reduction in time to determine total extractables from the biodegradable Biopol polymer with increased flow rate. 

L. Schafer, M. Cao, and M. J. Meadows, Predictions of Protein Backbone Bond Distances and Angles from First Principles, Biopol., 35 (1995) 603-606. 

Kabsch, W., and C. Sander. 1983. Dictionary of Protein Secondary Structure Pattern Recognition of Hydrogen-Bonded and Geometrical Features. Biopol. 22,2577-2637. 

Conformation of a System of Three Linked Peptide Units. Biopol. 6, 1425-1436. von Carlowitz, S., H. Oberhammer, H. Willner, and J. E. Boggs. 1986. Structural Determination of a Recalcitrant Molecule (S2F4). J. Mol. Struct. 100,161-177. von Carlowitz, S., W. Zeil, P. Pulay, and J. E. Boggs. 1982. The Molecular Structure, Vibrational Force Field, Spectral Frequencies, and Infrared Intensities of CH3POF2. J. Mol. Struct. (Theochem) 87, 113-124. 

So far, commercial applications have been developed only for poly(3HB-co-3HV) (Biopol) by ICI [52,142]. This material has been processed into bottles for hair care products (Wella) and biodegradable motor oil [84]. Moreover, various containers, disposable razors, and food trays for holding portions of fish and meat in the refrigerated section of supermarkets were all manufactured from Biopol and sold in Japan [84,143]. In these cases, the rather expensive Biopol is used solely for its green image in order to increase product sales and to open up the market for other applications, which require biodegradability for functional reasons [18]. 

Zeneca (1993) Brochure Biopol Resin Nature s Plastic, The Natural Choice Zeneca BioProducts, Billingham, UK... 

Fig. 1. Biodegradation of poly(HASCL). The bottles consist of the Biopol material and were in cubated in aerobic sewage sludge for 0,2,4,6, and 8 weeks, respectively (left to right)...

P. Cieplak, S. N. Rao, P. D. J. Grootenhuis, and P. A. Kollman, Free energy calculation on base specificity of drug-DNA interactions Application to daunomycin and acridine intercalation into DNA, Biopol. 29 717 (1990). 

In the 1970s, ICI introduced this polymer and copolymers in which it was the major constituent as commercial products, initially under the acronym PHB, and a little later under the trade name Biopol, which referred specifically to copolymers containing p-oxybutyrate and up to 30 % of P-oxyvalerate repeating units. The copolymer is more flexible and tougher than the homopolymer [100, 101]. 

BAK, Bioceta, Biomax, Bionelle, Biopol, Cortec, CPLA, Easter Bio, Ecoflex, Mater-Bi, Metabolix, Nature Works PLA, Nodax, PEC (polyester carbonate), PLA, Sky Green BDP... 

The disadvantages of all biochemical routes is the lack of variable tacticity in the polymer and, even more important, the need for time-consuming purification. PHB materials of feasible properties are only achieved with high production costs. In the 1990s, ICl sold a copolymer of 3-HB and 3-HV (BIOPOL) for about 10-20 /kg whereas the price of PP was less than 2 /kg. Therefore, a fermentative synthesis is feasible for smaller applications but not cannot compete with packaging materials such as poly(olefin)s [43 5] (Fig. 10). 

Production of polymers contributes to pollution during synthesis and after use. A polymer produced by microorganisms is already a commercial product (Biopol). Unfortunately, however, cellular synthesis remains limited by the cost of downstream processing and the fact that the synthesis is aqueous-based, and it is impossible to perform the synthesis in the absence of a solvent. Recent research describes an enzyme-catalyzed polymer synthesis in which there is no solvent. This bulk polymerization mirrors conventional synthesis but eliminates the needs for extremes of temperature and corrosive acid catalysts. This represents the first rapid and efficient synthesis of polyesters from bulk polymerization under ambient conditions with very low concentrations of a biocatalyst (Chaudhary et al., 1997). 

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