Dynamic Nanocellulose Networks for Thermoset-like yet Recyclable Plastics with a High Melt Stiffness and Creep Resistance
Artikel i vetenskaplig tidskrift, 2019

Many polymers, including polyethylene, feature a relatively low melting point and hence must be cross-linked to make them viable for applications that demand a high stiffness and creep resistance at elevated temperatures. The resulting thermoset plastics cannot be recycled, and therefore alternative materials with a reconfigurable internal network structure are in high demand. Here, we establish that such a thermoset-like yet recyclable material can be realized through the addition of a nanocellulose reinforcing agent. A network consisting of cellulose nanocrystals, nano- or microfibrils imparts many of the characteristics that are usually achieved through chemical cross-linking. For instance, the addition of only 7.5 wt % of either nanocellulose material significantly enhances the melt stiffness of an otherwise molten ethylene-acrylate copolymer by at least 1 order of magnitude. At the same time, the nanocellulose network reduces the meltcreep elongation to less than 10%, whereas the neat molten matrix would rupture. At high shear rates, however, the molten composites do not display a significantly higher viscosity than the copolymer matrix, and therefore retain the processability of a thermoplastic material. Repeated re-extrusion at 140 °C does not compromise the thermomechanical properties, which indicates a high degree of recyclability. The versatility of dynamic nanocellulose networks is illustrated by 3D printing of a cellulose composite, where the high melt stiffness improves the printability of the resin.

Författare

Anna Peterson

Chalmers, Kemi och kemiteknik, Tillämpad kemi, Christian Müller Group

Ida Östergren

Chalmers, Kemi och kemiteknik, Tillämpad kemi, Christian Müller Group

Antiope Lotsari

Chalmers, Kemi och kemiteknik, Tillämpad kemi, Martin Andersson Group

Abhijit Venkatesh

Chalmers, Industri- och materialvetenskap, Konstruktionsmaterial

Johannes Thunberg

Chalmers, Industri- och materialvetenskap, Konstruktionsmaterial

Anna Ström

Chalmers, Kemi och kemiteknik, Tillämpad kemi

Ramiro Rojas

Kungliga Tekniska Högskolan (KTH)

Wallenberg Wood Science Center (WWSC)

Martin Andersson

Chalmers, Kemi och kemiteknik, Tillämpad kemi, Martin Andersson Group

Lars A. Berglund

Wallenberg Wood Science Center (WWSC)

Kungliga Tekniska Högskolan (KTH)

Antal Boldizar

Chalmers, Industri- och materialvetenskap, Konstruktionsmaterial

Christian Müller

Chalmers, Kemi och kemiteknik, Tillämpad kemi, Christian Müller Group

Biomacromolecules

1525-7797 (ISSN) 1526-4602 (eISSN)

Vol. 20 10 3924-3932

Ämneskategorier

Polymerkemi

Materialteknik

Fysikalisk kemi

Kemi

DOI

10.1021/acs.biomac.9b00993

PubMed

31525970

Mer information

Senast uppdaterat

2019-11-11