Biodegradable basic properties

Despite its similarity to Ecoflex E, the new Ecoflex ES also shows significant differences that make it the material of choice for certain applications. One of these basic properties of Ecoflex ES is a significantly increased rate of biodegradation. This improves compostability in industrial composting facilities. 

Yang et al. discussed the basic properties of an implantable or extracorporeal artificial liver. The article focused on implantable devices but other than biodegradability, the properties of implantable devices are also applicable to extracorporeal devices. The focus of the article on implantable devices reveals an unfortunate prejudice on the part of much of the scientific community. Most researchers in this field are working on devices intended to be placed in the body. 

Table 13 Basic properties of a few of typical biodegradable synthetic polymers...

Growing discussion about the limited availability of cheap fossil basic materials, and customers paying more and more attention to product life cycles, brings aspects of the biodegradability of polymer products again to the focus of attention. The replacement of synthetic polymer products with biopolymers is attractive but limited because the properties of natural polymers do not always fit the demands of processability and final product performance. PVA with its beneficial rheological... 

Other published works relevant to estimation of properties and reactivity of chemicals may be of value to the reader. A book edited by Neely and Blau (1985) (Environmental Exposure from Chemicals) is less comprehensive but has several excellent chapters on basic information, such as the one on biodegradation by Klecka. Other volumes that may be useful include The Properties of Drugs, edited by Yalkowsky et al. (1980) and Aqueous Solubility by Yalkowsky and Banerjee (1991). Chemical Exposure Predictions, edited by Calamari (1993), is somewhat different in focus but may be useful for information on exposure modeling, especially for the soil compartment. 

JL HE POLYMERIZATION OF VINYL MONOMERS in the void spaces of bulk wood results in wood—polymer composites of increased strength properties and dimensional stability see Chapter 6). Because the different environmental conditions expose in-service timber to attack by numerous wood-deteriorating microorganisms, it is desirable to enhance the biodegradation resistance of wood, with simultaneous improvements in mechanical behavior. This chapter summarizes the formation of bioactive wood-polymer composites (1-4). The basic approach is still in situ polymerization of vinyl monomers in wood, with the appropriate choice of a bioactive, toxic, functional group incorporated in the monomer, and with other modifications based on wood-polymer reactions. 

PROPERTIES OF SPECIAL INTEREST Natural resources basic polysaccharides nontoxic biodegradability bioactivity biosynthesis interesting derivatives (chitosan) toughness graft copolymerization chelating ability for transition metal cations immobilizes enzymes by chemical linking or adsorption chiral polymer. 

Bulk characterization yields information on the macroscopic properties of the biomaterial such as thermal, mechanical, solubility, optical, and dielectric properties. Surface characterization yields morphological information that is critical for interfacing the implant or drug delivery device with the host tissue. This could be achieved by microscopic and spectfoscopic methods. Next in the hierarchy is the characterization of processes such as biodegradation mechanism and kinetics under biomimetic in vitro conditions. Cases of implanted device failure need to be assessed by systematic interrogation of explanted medical devices. After knowing the basic characteristics of the biomaterial, real-time investigation of in vivo processes plays a major role in the successful journey of an implant. 

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