Biodegradable polyamides synthesis

Other Synthetic Biodegradable Polymers Although well investigated for drug delivery, polyorthoesters, polyurethanes, and polyamides have found limited application as nanoparticles. A report documents the synthesis and characterization of polyorthoester nanoparticles [105],... 

In an effort to find another class of polymers which would be biodegradable, it appeared that the polyamides had many attractive features. In our laboratories, a new synthesis of polypeptides through the polymerization of the amino acid azide hydrobromides had been developed. Thus, it was feasible to extend this procedure to the synthesis of a dimer of glycine and e-aminocaproic acid followed by the polymerization of this dimer through the amino acid azide hydrobromide to the desired regularly alternating copolyamide of nylon 2/nylon 6 (4). 

Polyanionic polyamides are available by the condensation of polycar-boxyamino acids such as glutamic acid and aspartic acid. Thongh both homopolymers are known and claimed as biodegradable, aspartic acid is more amenable to a practical industrial thermal polymerization since it has no tendency to form an internal A-anhydride as is the case with glutamic acid. An alternative synthesis for polyaspartic acid is from ammonia and maleic acid. 

Jung and coworkers [84] described synthesis of biodegradable polymers consisting of the polyamide based dendrons and PNBE backbone (Figure 7.9). They reported ROMP of the first- and second-generation Newkome-style dendronized... 

Kawasaki, N., Nakayama, A., Yamano, N., Takeda, S., Kawata, Y, Yamamoto, N., and Aiba, S. [2005]. Synthesis, thermal and mechanical properties and biodegradation of branched polyamide 4, Polymer, 46,9987-9993. 

This book covers both fundamental and applied research associated with polymer-based nanocomposites, and presents possible directions for further development of high performanee nanocomposites. It has two main parts. Part I has 12 chapters which are entirely dedicated to those polymer nanocomposites containing layered silicates (clay) as an additive. Many thermoplastics, thermosets, and elastomers are included, such as polyamide (Chapter 1), polypropylene (Chapter 4), polystyrene (Chapter 5), poly(butylene terephthalate) (Chapter 9), poly(ethyl acrylate) (Chapter 6), epoxy resin (Chapter 2), biodegradable polymers (Chapter 3), water soluble polymers (Chapter 8), acrylate photopolymers (Chapter 7) and rubbers (Chapter 12). In addition to synthesis and structural characterisation of polymer/clay nanocomposites, their unique physical properties like flame retardancy (Chapter 10) and gas/liquid barrier (Chapter 11) properties are also discussed. Furthermore, the crystallisation behaviour of polymer/clay nanocomposites and the significance of chemical compatibility between a polymer and clay in affecting clay dispersion are also considered. 

---