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Updated: Jul 5, 2026
11:49
Synthesis of Soft Polysiloxane-urea Elastomers for Intraocular Lens Application
Published on: March 8, 2019
Surface characterization of biocidal polyurethane modifiers having poly(3,3-substituted)oxetane soft blocks with
Pinar Kurt1, Lara J Gamble, Kenneth J Wynne
1Department of Chemical and Life Science Engineering, Virginia Commonwealth University, Richmond, VA 23284, USA.
Summary
Surface characterization of polyurethanes reveals that while fluorous components drive nanoscale morphology, antimicrobial effectiveness is more influenced by alkylammonium chain length. This impacts surface concentration and biocidal properties.
Area of Science:
- Polymer Science
- Materials Science
- Surface Chemistry
Background:
- Polyurethanes with fluorous (3FOx) or PEG-like (ME2Ox) A side chains and alkylammonium B side chains were synthesized.
- Previous studies established an order of antimicrobial effectiveness for these surface modifiers.
Purpose of the Study:
- To characterize the surfaces of P[AB] copolyoxetane soft block polyurethanes.
- To correlate surface properties with observed antimicrobial effectiveness.
Main Methods:
- X-ray Photoelectron Spectroscopy (XPS)
- Contact Angle measurements
- Attenuated Total Reflectance Infrared (ATR-IR) spectroscopy
- Time-Resolved Atomic Force Microscopy (TM-AFM) phase imaging
Main Results:
- Significant surface concentration of fluorous P[AB]-polyurethane modifiers (2 wt%) was confirmed by XPS, contact angles, ATR-IR, and TM-AFM.
- The most effective biocidal modifier, 2 wt% HMDI-BD(30)/P[(3FOx)(C12)-0.89:0.11]-PU, exhibited nanoscale phase separation (200 nm domains).
- Nanoscale morphology was primarily influenced by the fluorous component, while antimicrobial activity correlated more strongly with alkylammonium chain length.
Conclusions:
- Surface morphology is dictated by the fluorous side chains, but antimicrobial performance depends on alkylammonium chain length.
- The impact of alkylammonium chain length on surface concentration and antimicrobial behavior is more significant in ME2Ox polyurethanes than in 3FOx analogs.
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