Microfibrillated cellulose suspensions dried on glass slides. (A) MFC obtained by mechanical homogenisation. Note the relatively large structures remaining after a homogenisation process. The inset shows structures composed mainly of nanofibrils. (B) MFC obtained with TEMPO-mediated oxidation as pre-treatment and mechanical homogenisation. The inset shows the nanofibrils having relatively homogeneous sizes. Both MFC materials (A and B) have been collected after passing five times through the homogeniser, at 1,000 bar.