Computational Study of Polylactic Acid Synthesis Methods Using N-aryl/N'-aryl Formazanate Zinc Catalysts

Feng, Xintao (2023) Computational Study of Polylactic Acid Synthesis Methods Using N-aryl/N'-aryl Formazanate Zinc Catalysts. Master's Thesis / Essay, Chemistry.

Preview	Text Master thesis.pdf Download (2MB) | Preview
	Text toestemming.pdf Restricted to Registered users only Download (141kB)

Abstract

Polylactic acid (PLA) is known for its biodegradability and sustainability. In recent years, because of the overuse of petroleum resources leading to excessive greenhouse gas (GHG) emission, the frequent occurrence of extreme weather has increased public concern about protecting the environment. Increasing emphasis is being placed on the concept of using bioplastics to address the growing environmental hazards of the overuse of conventional plastics. This requires advanced synthetic solutions to generate PLA, which may be achieved by ring-opening polymerization (ROP) with lactide (LA) as the monomer. This thesis presents a theoretical study for the synthesis of PLA using zinc formazanate complexes as redox-active complexes, proposing two reaction mechanisms for the production of PLA as well as establishing three reaction pathways. In this research, a series of computational calculations were carried out using density functional theory (DFT) for ROPs catalyzed by formazanate Zn(II) complexes. This study also compared bond distances and free energies calculated by the DFT and DFTB (Density-Functional based Tight-Binding) methods. By comparing the free energy changes given by other theoretical calculations and the reaction constants calculated from the experimental data, it was found that the Gibbs free energy difference of the pathway using the radical zinc complex is within a reasonable range of error and has a higher rate constant.

Item Type:	Thesis (Master's Thesis / Essay)
Supervisor name:	Havenith, R.W.A. and Otten, E.
Degree programme:	Chemistry
Thesis type:	Master's Thesis / Essay
Language:	English
Date Deposited:	06 Feb 2023 12:57
Last Modified:	06 Feb 2023 12:57
URI:	https://fse.studenttheses.ub.rug.nl/id/eprint/29224

Actions (login required)

View Item