The project will involve the use of advanced computational techniques such as molecular dynamics (MD) simulation.

Purpose

Poly (lactic acid) or PLA is a biodegradable and biocompatible polymer which can be synthesized from renewable feedstocks and can potentially replace oil-derived plastics such as PS, PET and PP in some applications. For example, with modified physical properties, especially reduced gas permeability, this polymer will be suitable for a wide range of uses in food packaging. In order to modify the gas barrier properties of poly (lactic acid), the incorporation of nano-scale clay by dispersion in the bulk polymer matrix is an attractive option. Complete delamination (separation) of the clay platelets yields an exfoliated nanomorphology which is desirable if significant reductions in gas permeability are to be achieved. The purpose of this project will be to develop a framework for predicting gas barrier properties of a PLA-layered double hydroxide (LDH) clay nanocomposite.

Description

The project will involve the use of advanced computational techniques such as molecular dynamics (MD) simulation. MD simulations can be an effective tool to predict diffusion processes in polymer matrices and this technique will be applied to better understand oxygen/water vapour diffusion in PLA-LDH clay nanocomposites. The plan would be to construct a three-dimensional unit cell consisting of long PLA chains in combination with LDH clay platelets and then study the time trajectories of all the constituent atoms, including the diffusant molecules in the energy-minimized unit cells. Diffusion coefficients would be determined by recognizing the random walk motion of the diffusing gas. The work will also aim to evaluate permeability coefficients using various constraints such as size, shape and concentration of the LDH clay in the PLA matrix through various combinations of PVT, NPT and NVE ensembles. The research will be relevant to the NanoPack project funded by the Danish Strategic Research Council.

Qualifications

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

Project form

Thesis

Subjects

Chemistry

Duration