Effect of moisture on processing of dialcohol cellulose affecting design of processing equipment?

PI: Anette Larsson, Chalmers, Giada Lo Re, Chalmers, Per Larsson, KTH, Jan Wahlberg, Tetra Pak 
PhD Student/Postdoc: Katarina Jonasson
Duration: 2021-05-01 – 2026-05-31

Intro                                                                                                                                                                                 

While thermoplastic behavior of cellulose is challenging, we know that dialcohol cellulose exhibit thermoplastic behavior in terms of softening, increased ductility, and melt processability. However, it is somewhat difficult to process dry dialcohol cellulose, resulting in high process forces and high temperatures causing discoloration of the material. It has been shown that the melt processability of dialcohol cellulose can be improved by addition of water, making it possible to process 100 % partly modified fibers at temperatures below 140oC, without causing discoloration of the material. Water is thus acting as a plasticizer for dialcohol cellulose. The proposed project will also support the work on detailed mechanisms between dialcohol and water that is to be investigated in the parallel modelling project “#4 - Prediction of thermoplasticity in lignocellulose materials with the use of simulations”.

Objectives                                                                                                                                                                            
  
Scientific: The aim is to understand the effect of moisture on partly modified dialcohol cellulose fibers during melt processing. In more detail to understand if the moisture only softens the dialcohole cellulose surface of the fibers or if the moisture deforms the cellulose core of the fiber or if it is a combination of the two alternatives.

Technical: To obtain knowledge to support design of process equipment mainly for extrusion and injection moulding for processing of dialcohol cellulose (mainly screw configurations).

Description of how this project addresses the hypotheses in FibRe                                                                     

By investigating the effect of moisture on the partly modified dialcohol cellulose during the extrusion process it will contribute to the understanding of hypothesis (2) of modification of the fiber surface for thermoformability of cellulose.

Page manager Published: Wed 28 Sep 2022.