[Synthesis and characterization of PEG-segmented polyurethane]

Area of Science:

• Polymer Science
• Materials Science
• Biomedical Engineering

Background:

• Polyurethanes (PUs) are versatile polymers with tunable properties.
• PEG-segmented PUs offer potential for biomedical applications due to their biocompatibility and hydrophilicity.

Purpose of the Study:

• To synthesize and characterize PEG-segmented polyurethanes with varying hard segment percentages.
• To evaluate the influence of hard segment content on material properties, including mechanical strength, surface hydrophilicity, and water vapor transmission rate (WVTR).

Main Methods:

• Bulk polymerization was employed to synthesize polyurethanes (PU-H40, PU-H50, PU-H55) with 40%, 50%, and 55% hard segment content, respectively.
• Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and gel permeation chromatography (GPC) were used for structural characterization.
• Mechanical testing, water contact angle measurements, and WVTR assessments were conducted.

Main Results:

• FTIR and DSC confirmed increased microphase separation with higher hard segment content.
• PU-H50 demonstrated the highest tensile strength at 25 MPa.
• The use of PEG as a soft segment significantly enhanced surface hydrophilicity, with PU-H55 achieving a water contact angle of 33 degrees.
• WVTR values decreased with increasing hard segment content, ranging from 789 g/m²/24h (PU-H40) to 623 g/m²/24h (PU-H55).

Conclusions:

• The synthesized PEG-segmented polyurethanes exhibit a strong correlation between hard segment content and microphase separation, mechanical properties, and hydrophilicity.
• The materials possess a favorable balance of mechanical strength, surface hydrophilicity, and controlled water vapor transmission.
• These polyurethanes are promising candidates for fabricating biomedical articles such as surgical gloves, wound dressings, and protective coatings.