Date of Award

8-2023

Document Type

Dissertation

Degree Name

Doctor of Philosophy (PhD)

Department

Chemistry

Committee Chair/Advisor

Rhett C. Smith

Committee Member

Stephen Creager

Committee Member

Shiou-Jyh Hwu

Committee Member

Byoungmoo Kim

Abstract

The production of Ordinary Portland Cement (OPC) and its uses have a complicated environmental impact, which is influenced by infrastructure development and building operations as well as CO2 emissions, which account for 7% of all worldwide CO2 emissions. Due to the increasing population, production is still ongoing. The search for cement and construction materials produced with zero to low CO2 emissions is therefore continuous. Finding recyclable, CO2 gas-free biocomposites with high sulfur content that can rival the mechanical properties of popular building supplies like Portland cement is the primary objective of the research discussed in this dissertation.

Chapter one describes the terpenoid as a substitution for olefins in commercially derived polymers. There is an emerging trend in substituting petrochemical derived polymers with sustainable biopolymers to the most commonly used commercial polymers. Terpenoid is an abundant, inexpensive monomer which as characteristic properties and most importantly, polymerizable alkene. Therefore, terpenoids have undergone relatively significant research as starting material for polymer synthesis.

Chapter two elaborates the process of inverse vulcanization used to create composites of sulfur-crosslinked terpenoids. It is investigated how High Sulfur Materials (HSMs) with a biopolymeric agent can create a stable sulfur network. Also included are the mechanical, thermal, and mechanical integrity aspects of recycling. And it discusses the investigation of terpenoid cyclization mechanism.

The degree to which the amount of terpenoid olefins and the ratio of sulfur to terpenoid affect the thermal and mechanical properties of such terpenoid-sulfur composites is described in the chapter three.

Plastic waste pollution of the environment is becoming a significant concern to both human health and the ecosystem. However, even post-consumer plastics that could be easily recycled using straightforward chemical procedures are nonetheless frequently dumped in landfills. Chapter four presents a straightforward, one-stage method for chemically recycling PET to produce composites with mechanical and thermal properties that are competitive with those of widely used structural materials like Portland cement.

Chapter five reports the creation and evaluation of mechanical, morphological and thermal properties of a group of composites made of different proportion of guaiacol generated from lignin, fatty acids, and sulfur. To evaluate the impact of unsaturation level on composites, monounsaturated oleic acid and diunsaturated linoleic acid were both employed as the fatty acid components.

Author ORCID Identifier

https://orcid.org/0000-0002-0510-1711

Share

COinS
 
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.