Controlled biodegradability

Patterson JW, Kodukala PS. 1981. Emission and effluent control biodegradation. Chem Eng Prog 77 48-55. 

A controllable biodegradability, desirable mechanical properties, suitable gas permeability and selectivity would extend the potential application areas of aliphatic polyesters not only in agriculture or in the greenhouse or packaging industry but also as a substitute for human skin. There is a need for such focused studies in the future. 

Macrodistribution. The ability of any wood preservative to control biodegradation is affected by the macrodistribution of the chemical within the wood product being protected. The macrodistribution of a preservative is influenced by three basic factors wood characteristics, treating process, and characteristics of the treating solution. Consideration of the principles of flow in wood and of the factors that influence the treatment of wood are covered in Chapters 3 and 4 14, 15). Suffice it to say that when the preservative has been distributed through the wood, fixation will occur either through chemical interaction between the preservative and the wood structure, between the preservative components themselves, or by physical deposition as a result of solvent loss. These fixation mechanisms are covered in the section on microdistribution. 

A number of general reviews on polyphosphazenes have appeared. Specific reviews on polyphosphazenes deal with radiation graft polymerization, anionic polymerization, hydrogel microspheres,controlled biodegradability,coatings, and membrane separation. 

Test Criterion Validity of the test positive control Biodegradability of the material sample test... 

Controlled biodegradability after effective use is another important factor in favor of biofiber composite. Life cycle analysis of these products can be carried out to evaluate the durability and consistency of these products for various engineering applications. 

Kopecek J. Controlled biodegradability of polymers-key to drug delivery systems. Biomaterials 1984 5 19-25. 

Poly(vinyl alcohol) (PVA), a well-known water-soluble and biodegradable polymer, has been used as an initiator for the microwave-assisted bulk ROP of s-caprolactone in a domestic microwave oven. The graft procedure proved to be an excellent method for functionalizing presynthesized polymers in order to specifically tailor their properties. In contrast to PVA, poly(e-caprolactone) (PCL) is hydro-phobic and degrades very slowly. The combination of the two polymers proves to be an attractive way to control biodegradability of the final material. In addition, the resultant poly(vinyl alcohol)-gra/f-poly(e-caprolactone) (PVA-g-PCL) had improved mechanical and thermal properties compared to the parent PVA. 

Despite successful results from in vitro studies, however, the clinical applications of systems that are based on polyNlPAAm may be limited, becanse poly-NIPAAm is nondegradable and insoluble. In addition, a major problem of polyNIPAAm-based drug deUvery systems is that thermal treatment is required for controlled destabilization of the micelles and concurrent drug release, which is not always feasible in clinical situations. Therefore, to overcome the disadvantages of polyNIPAAm, controlled biodegradable systems that use polyester block copolymers as thermosensitive polymers have been investigated. 

Biocompatibility with a controllable biodegradability and susceptibility to chemical modification... 

Chitosan is a unique natural polymer that has potential in tissue engineering applications due to its controllable biodegradability, biocompatibility, antimicrobial activity, and functionalizability. A great number of studies have been performed to evaluate the cytocompatibility of chitosan... 

It is known for a long time that aliphatic polyesters can be hydrolysed by lipases and other hydrolases. As parameters controlling biodegradability different parameters were discussed. The specific structure of the ester bond was supposed to be of importance, but also the hydrophobic-hydrophilic balance in neighbourhood to the ester and thermal properties like the melting point were regarded ". ... 

Key words in situ polymerizable biomaterials, controlled biodegradation, non-cytotoxic degradation products, environmentally responsive biomaterials. 

Tsuji, H., Nishikawa, M., Osanai, Y. and Matsumura, S. (2007) New strategy for controlling biodegradability of biodegradable polyesters by enzyme-catalyzed surface grafting. Macromolecular Rapid Communications, 28, 1651-1656. 

An ideal scaffold should possess excellent biocompatibility, controllable biodegradability and suitable mechanical characteristics. Several studies have shown that nanofibrous scaffolds can enhance cellular responses like cell adhesion and cell phenotype maintenance. Electrospun PCL nanofibrous scaffolds can be fabricated in the laboratory for the treatment of partial or full thickness skin defects. These nanofibrous wound dressings, due to their porosity and inherent properties might... 

Takahashi and H. lida. Biodegradable plastics composition, molded article of the composition, and method of controlling biodegradation rate, US Patent 7816424, assigned to Nisshinbo Industries, Inc. (Tokyo, JP), October 19,2010. 

Fujimoto Y, Sinha Ray S., Okamoto M., Ogami A., Yamada K., Ueda K., Well-controlled biodegradable nanocomposite foams From microcellular to nanoceUular, Macromol. Rapid. Commun., 24, 2003, 457 61. 

Y. Fujimoto, et al, Well-controlled biodegradable nanocomposite foams from microcel-lular to nanocellular, Macromolecular Rapid Communications 24 (7) (2003) 457-461. 

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