Purpose

Biodegradable poly (lactic) acid-clay nanocomposites (PLACN) are of interest because of their increased mechanical, thermal and gas barrier properties, solvent resistance and decreased flammability relative to the corresponding bulk poly (lactic) acid (PLA). The tailoring of these properties is critically dependent on the dispersion of ~ 1nm thick individual clay platelets in the bulk PLA matrix and the nanomorphology (i.e., intercalated, exfoliated or mixed intercalated/exfoliated). Commercial clays are available in modified form in which the presence of an organic modifier makes the clay surface more hydrophobic and subsequently provides a favorable interactive environment between clay and PLA matrix for nano-level dispersion. Although the selection of the modifier and its architecture plays a crucial role in PLACN preparation, fundamental understanding of modifier/clay surface interaction is still limited in the literature. The purpose of the project will be to apply state-of-the-art computational techniques to better understand such interactions and to assist in the development of next generation of PLA nanocomposites for practical applications.

Description

In this project we will prepare virtual PLACN models with different modifier architectures by using computational techniques such as Density Functional Theory and/or ab initio studies. These computational tools will be utilized to find out the energy interaction within and between PLA molecules, clay surfaces, and modifier molecules. The objective of this study is to find out the dependency of modifier functionalization on the nanomorphology of PLACN. On the basis of theoretical reasoning, experimental studies will be undertaken to achieve optimized and targeted nanomorphology in PLACN. The proposed PLACN studies on prediction of nanomorphology (i.e., intercalated, exfoliated or mixed intercalated/exfoliated) could have significant impact on the selection of these materials for various end use applications. The research will be relevant to the NanoPack project funded by the Danish Strategic Research Council and the successful applicant will be jointly supervised by Senior Scientist David Plackett, Risø DTU and Associate Professor Stephan Sauer, Department of Chemistry, University of Copenhagen.

Qualifications

Applicants for this project should have an interest in theoretical chemistry and the application of computer modeling techniques to predict material properties.

Project form

Final year project

Subjects

Chemistry

Duration