Robust methylcellulose hydrogels reinforced with chitin nanocrystals

Area of Science:

• Materials Science
• Biomaterials Engineering
• Polymer Chemistry

Background:

• Chitin nanocrystals (ChNCs) are explored as reinforcing agents in polymer nanocomposites.
• Alpha-chitin nanocrystals (α-ChNCs) from crustacean shells are commonly used, exhibiting a rod-like morphology.
• Developing novel sources and types of chitin nanocrystals is crucial for advanced material applications.

Purpose of the Study:

• To investigate the potential of beta-chitin nanocrystals (β-ChNCs) as reinforcing nanomaterials for methylcellulose (MC) hydrogels.
• To characterize the morphology and stability of β-ChNCs derived from cuttlefish bone.
• To evaluate the impact of β-ChNCs on the formation rate and mechanical properties of MC hydrogels.

Main Methods:

• Beta-chitin nanocrystals (β-ChNCs) were extracted from cuttlefish bone via acid hydrolysis.
• Novel β-ChNCs exhibited an irregularly granular morphology, distinct from rod-like α-ChNCs.
• Methylcellulose (MC) hydrogels were fabricated by mechanically mixing MC with aqueous β-ChNC suspensions.

Main Results:

• The incorporation of β-ChNCs significantly accelerated the gelation rate of MC hydrogels.
• Mechanical strength of the MC nanocomposite hydrogels was dramatically enhanced, even at low β-ChNC content.
• Dual physical crosslinking, involving β-ChNCs and MC chains, was proposed as the mechanism for improved properties.

Conclusions:

• Beta-chitin nanocrystals (β-ChNCs) are effective reinforcing agents for methylcellulose (MC) hydrogels.
• The unique granular morphology of β-ChNCs contributes to enhanced hydrogel properties through dual physical crosslinking.
• These robust MC composite hydrogels demonstrate considerable potential for diverse biomedical applications.