Infectious diseases can disseminate through various means, with one prevalent mode being transmission via contaminated surfaces. This is a widespread issue, particularly in hospitals, contributing to the increase in nosocomial infections and associated fatalities. Anti-microbial surfaces can play a pivotal role in reducing the spread of diseases and can find applications in hospital beds/chairs, the public transportation sector, and others. COVID-19 further heightened the need for such anti-microbial surfaces. Plastics, widely used in every aspect of life, have no inherent biocidal properties. Therefore, plastic articles/surfaces lack any defense against accumulating infectious diseases on the surfaces. Efforts are undertaken in this direction to create anti-microbial polymers. Even though these approaches have been demonstrated to be effective anti-microbial agents, they have limited opportunities for commercialization at an industrial scale. For large-scale commercial applications, a simple process to render plastics anti-microbial will be to incorporate various inorganic crystal biocides via compounding. Traditional leachable biocides are utilized by this approach in making plastics anti-microbial. Nevertheless, the use of leachable biocides raises safety concerns. Conversely, non-leachable antimicrobial agents, which are safe, exhibit reduced effectiveness when incorporated into plastics through blending methods.This Ph.D. dissertation aims to develop novel methods for incorporating anti-microbial biocidal nanoparticles into thermoplastics. In this regard, the anti-microbial activity of leachable and non-leachable biocidal nanoparticles was tested after being incorporated into thermoplastic material via both melt-compounding and surface embossing. Properties of the thermoplastic composite, such as thermal, rheological, mechanical, flowability, permeability, and leachability, are studied before and after the addition of anti-microbial. A novel methodology of incorporating the nanoparticles into the surface of thermoplastics through thermal embossing is developed and compared with the traditional melt-blending approach. The study demonstrates the effectiveness of surface embossing as compared to melt-blending for the non-leachable anti-microbial agents. The study also confirms the ROS mechanism for the non-leachable magnesium hydroxide and copper infused magnesium hydroxide nanoparticles.
Read
