Microscopic Insight into the Structure-Processing-Property Relationships of Core-Shell Structured Dialcohol Cellulose...

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Materials Engineering

Background:

• Cellulose is a sustainable alternative to synthetic polymers but lacks thermoplasticity, hindering melt processing.
• Chemical modification, such as creating dialcohol cellulose, can enhance cellulose's thermoplastic properties.
• Understanding molecular interactions is crucial for optimizing melt processing of modified cellulose.

Purpose of the Study:

• To investigate the molecular interactions and structure-property relationships of dialcohol cellulose nanocrystals during melt processing.
• To correlate molecular dynamics simulations with experimental melt extrusion data.
• To assess the impact of modification degree and water content on cellulose fiber processability.

Main Methods:

• Molecular dynamics simulations of dialcohol cellulose nanocrystals under mechanical shearing.
• Experimental fiber extrusion of dialcohol cellulose with varying modification degrees and water content.
• Analysis of stress, interfacial stiffness, hydrogen bonding, and friction.

Main Results:

• Shearing behavior (stress, stiffness, H-bonds, conformation) depends on modification degree, water, and temperature.
• Increased modification and water content facilitate melt processing, aligning with simulation predictions.
• Dialcohol cellulose modification significantly reduces inter-crystal friction, especially with increasing temperature.

Conclusions:

• Molecular modeling provides fundamental insights into structure-property relationships for modified nanocellulose.
• Optimizing dialcohol cellulose modification and water content is key for developing advanced cellulose-based biomaterials.
• This study validates the use of molecular dynamics for predicting and improving melt-processing characteristics of cellulose derivatives.