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Synthesis of Soft Polysiloxane-urea Elastomers for Intraocular Lens Application
Published on: March 8, 2019
Surface characteristics of polyurethane elastomers based on chitin/1,4-butane diol blends
Khalid Mahmood Zia1, Mehdi Barikani, Mohammad Zuber
1Department of Chemistry, University of Agriculture, Faisalabad 38040, Pakistan.
International Journal of Biological Macromolecules
|January 10, 2009
Summary
Researchers synthesized biodegradable polyurethane elastomers with tunable hydrophobicity by incorporating chitin. Increasing chitin content decreased surface free energy and water adhesion, suggesting potential for non-absorbable sutures.
Area of Science:
- Polymer Chemistry
- Materials Science
- Biomaterials
Background:
- Biodegradable polymers are crucial for biomedical applications.
- Polyurethanes (PUs) offer versatile properties but require tailored surface characteristics.
- Chitin is a biocompatible natural polymer with potential for surface modification.
Purpose of the Study:
- To synthesize biodegradable polyurethane elastomers with tunable hydrophobicity.
- To investigate the effect of chitin incorporation on the surface properties of PUs.
- To evaluate the potential of chitin-modified PUs as non-absorbable sutures.
Main Methods:
- Step-growth polymerization using poly(epsilon-caprolactone) (PCL) and 4,4'-diphenylmethane diisocyanate (MDI).
- Chain extension of prepolymer with varying ratios of chitin and 1,4-butane diol (BDO).
- Characterization of surface properties via contact angle measurements, water absorption, and swelling behavior analysis.
Main Results:
- Incorporation of chitin decreased surface free energy and its polar component.
- Increased chitin content significantly reduced the work of water adhesion.
- Surface properties, solvent interactions, and swelling behavior were dependent on chitin content.
Conclusions:
- Synthesized biodegradable PUs exhibit tunable hydrophobicity modulated by chitin content.
- The modified PUs demonstrate reduced surface energy and water adhesion.
- These chitin-modified polyurethanes show promise as non-absorbable suture materials, building on prior biocompatibility studies.
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