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Updated: Jan 28, 2026
11:49
Synthesis of Soft Polysiloxane-urea Elastomers for Intraocular Lens Application
Published on: March 8, 2019
13.1K
In vitro oxidative stability of high strength siloxane poly(urethane-urea) elastomers based on linked-macrodiol
Loshini S Dandeniyage1,2, Warren Knower2, Raju Adhikari2
1School of Science, RMIT University, Melbourne, Victoria, 3000, Australia.
Summary
Two novel siloxane poly(urethane urea)s (SiPUU-1 and SiPUU-2) demonstrate excellent oxidative stability, comparable to commercial siloxane polyurethanes. These materials show minimal degradation and strength loss, making them promising for biomedical applications.
Area of Science:
- Biomaterials Science
- Polymer Chemistry
- Materials Degradation
Background:
- Polyurethanes are widely used in biomedical applications.
- Oxidative degradation can limit the lifespan and performance of polyurethanes in physiological environments.
- Siloxane-based polyurethanes offer potential improvements in biocompatibility and stability.
Purpose of the Study:
- To evaluate the in vitro oxidative stability of two newly synthesized siloxane poly(urethane urea)s (SiPUU-1 and SiPUU-2).
- To compare the oxidative stability of SiPUU-1 and SiPUU-2 against commercially available polyurethanes.
- To assess the impact of oxidative stress on the physical and chemical properties of these materials.
Main Methods:
- Synthesized SiPUU-1 (using 4,4'-methylenediphenyl diisocyanate) and SiPUU-2 (using Isophorone diisocyanate).
- Exposed materials to oxidative conditions (20% H2O2, 0.1 mol/L CoCl2, 37°C, 150% strain) for 90 days.
- Utilized SEM, ATR-FTIR, molecular weight analysis, and tensile testing to assess degradation.
Main Results:
- SiPUU-1, SiPUU-2, and Elast-Eon™ 2A showed no significant surface degradation.
- ChronoThane P™ 80A exhibited extensive degradation, while ChronoSil™ 80A degraded in both soft and hard segments.
- SiPUU-1 and Elast-Eon™ 2A experienced only 13-14% loss in ultimate tensile strength, compared to 35% for ChronoThane P™ 80A.
Conclusions:
- SiPUU-1 demonstrates oxidative stability comparable to the commercial siloxane polyurethane Elast-Eon™ 2A.
- The synthesized SiPUU materials exhibit superior resistance to oxidative degradation compared to ChronoThane P™ 80A.
- These findings suggest SiPUU-1 and SiPUU-2 are promising candidates for biomedical applications requiring oxidative stability.
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