3. Acknowledgements

We are thankful to the Industrial Biotechnology Innovation Centre (IBioIC) for funding. M.C. acknowledges the department of Chemical Engineering of the University of Bologna for a study abroad scholarship; U.S. acknowledges UoE for funding her PhD scholarship; G.G.R. acknowledges Conacyt for funding his PhD scholarship; S.S. acknowledges UoE for funding his undergraduate research scholarship. We also acknowledge the use of the Cryo FIB/SEM bought with the EPSRC grant EP/P030564/1 and Thomas Glen for help with the image acquisition. We are also grateful to BASF, IGM resins and Arkema-Sartomer for providing us with free samples.