1. EMRE Specialties Technology Division, ExxonMobil, 5200 Bayway Drive, Btec West Main Building, Baytown, Texas 77520, United States
2. Contextualize (Pty) Ltd., Wavecrest, Strand 7140, South Africa
3. Department of Chemistry and Polymer Science, University of Stellenbosch, Private Bag X1, 7602 Matieland, South Africa