Graphene Meeting, 31 October 2017

Present: Bjarke Jørgensen(NEWTEC), Bjarke Jensen(NEWTEC), Emil Bjerglund (AU), Jacob(SDU), Jacob(DTI), Kim Daasbjerg(AU), Iben Kongsfelt(OS), Stine Kristensen(OS), Susie-Ann Spiegelhauer(SP Group), Jens Frandsen(KU), Kasper Nørgaard(KU), Rasmus(KU)

Agenda

  1. Welcome
  2. Project status, Emil
  3. Project status, Jens
  4. Tour at NEWTEC
  5. Extruder

 

Project status, Emil Bjerglund, AU

Emil is PhD student at AU and has 1 yr. left of his studies. He is not full-time Open Science but has been involved in the graphene project since the beginning through Andreas Laursen (OS bachelor student, spring 2017). This part of the project concerned the production of amine-functionalized graphene in a one-pot process through oxidative exfoliation in a solvent containing diazonium salt. The graphene was incorporated in PUR.

The diazonium functionalized graphene in PUR increases strength of PUR with app. 45%, unfunctionalized graphene in PUR does not increase strength.

This part of the project focus on increased production of graphene for OS companies to test – so far it is possible to produce app. 3g/h.

Challenges:

  • Heat production during exfoliation result in diazonium decay within 40 minutes.
    • Suggested solutions: Cooling or continues addition of diazonium salts
  • Freeze drying volume too small.
    • AU-Food have large freeze dryers
    • Spray-drying (DTI may have the equipment)
    • Precipitate by polymerization
    • Increase solubility by increasing degree of functionalization or by longer-chain functionalization
    • Increase solubility by changing the counter-ion
    • Choose another solvent than water – isopropanol?
    • Acquire freeze dryer for open science through Novo Nordisk or through crowdfunding

Interest in other types of functionalization?
The “handle” is easily changed

  • Thiol to capture gold-nanoparticles for use in electro catalysis
  • Sulfonate group will increase solubility and function as a negative stable group

Plans:
Continue production to deliver graphene to interested companies while optimizing the process.

Data and reports
Emil will place data, reports, calculations etc. on Github https://emiltb.github.io/graphene-production/lab_journal.html and ask if discussions and comments will be placed here to let everyone access the discussions.

Project status, Jens Frandsen, KU

Jens is master student at KU, he will do half the project at KU and half the project in China. The plan is to do graphene synthesis in Denmark and characterization in China.

Purpose of the project: Synthesis of graphene oxide and blend in polymer to transfer graphene-properties to polymer through crosslinking functional groups of graphene to functional groups of polymers.

The study will focus on:

  • Conductivity and oxidation
  • Solubility – how is the graphene dispersed – will it restack

Choices

  • Graphite flake size (big, medium, small)
  • GO synthesis (Marc’s GO3, Hummers modified(90C, 6wt), Hummers modified(0C, 6wt), hummers modified(0C, 2wt))
  • Polymer blend method(solvent blend, melt compound, extrusion)
  • GO ratio in polymer?
  • Polymer choice
    • Resin or PLA to be used in 3D printing (combine with the OS project on 3D printing)
    • Silicon-based material
    • PUR or poly-ethylene for Bulk production
      • For migration tests, NEWTEC are ready to help