ABSTRACT
Nowadays, increasing population, widespread urbanization, rise in living standards together with versatile use of polymers have caused non-biodegradable polymeric wastes affecting the environment a chronic global problem, simultaneously, the existing high energy demand in our society is a matter of great concern. Hence forth, this review article provides an insight into the technological approach of pyrolysis emphasizing catalytic pyrolysis for conversion of polymeric wastes into energy products and presents an alternative waste management technique which is a leap towards developing sustainable environment. Pyrolysis of waste non-biodegradable polymer materials involves controlled thermal decomposition in the absence of oxygen, cracking their macromolecules into lower molecular weight ones, resulting into the formation of a wide range of products from hydrogen, hydrocarbons to coke. Nanocatalyzed pyrolysis is a recommended solution to the low thermal conductivity of polymers, promoting faster reactions in breaking the C-C bonds at lower temperatures, denoting less energy consumption and enabling enhancement in the process selectivity, whereby higher value added products are generated with increased yield. Nanotechnology plays an indispensable role in academic research as well as in industrial applications. Existing reviews illustrate that one of the oldest application field of nanotechnology is in the arena of nanocatalysis. Nanocatalysis closes the gap between homo and heterogeneous catalyses while combines their advantageous characteristics and positive aspects, reducing the respective drawbacks. During the current nanohype, nanostructured catalysts are esteemed materials and their exploration provide promising solutions for challenges from the perspective of cost and factors influencing catalytic activity, due to their featured high surface area to volume ratio which render enhanced properties with respect to the bulk catalyst.
ABSTRACT
This review article presents an overview of the potential biomedical application of polymer nanocomposites arising from different chemistries, compositions, and constructions. The interaction between the chosen matrix and the filler is of critical importance. The existing polymer used in the biomedical arena includes aliphatic polyesters such as polylactide (PLA), poly(ε-caprolactone) (PCL), poly(p-dioxanone) (PPDO), poly(butylenes succinate) (PBS), poly(hydroxyalkanoate)s, and natural biopolymers such as starch, cellulose, chitin, chitosan, lignin, and proteins. The nanosized fillers utilized to fabricate the nanocomposites are inorganic, organic, and metal particles such as clays, magnetites, hydroxyapatite, nanotubes chitin whiskers, lignin, cellulose, Au, Ag, Cu, etc. These nanomaterials are taking root in a variety of diverse healthcare applications in the sector of nanomedicine including the domain of medical implants and devices. Despite sterilization and aseptic procedures the use of these biomedical devices and prosthesis to improve the patient's 'quality of life' is facing a major impediment because of bacterial colonization causing nosocomial infection, together with the multi-drug-resistant 'super-bugs' posing a serious threat to its utility. This paper discusses the current efforts and key research challenges in the development of self-sterilizing nanocomposite biomaterials for potential application in this area.
