Characterization, biodegradability and blood compatibility of poly[(R)-3-hydroxybutyrate] based poly(ester-urethane)s

Area of Science:

• Polymer Chemistry
• Biomaterials Science
• Materials Engineering

Background:

• Poly(ester-urethane)s (PUs) are versatile polymers with tunable properties.
• Developing biodegradable and hemocompatible materials is crucial for biomedical applications.
• Combining poly(R-3-hydroxybutyrate) (PHB) and poly(epsilon-caprolactone) (PCL) offers potential for novel PUs.

Purpose of the Study:

• To synthesize and characterize novel multiblock poly(ester-urethane)s.
• To investigate the influence of PHB and PCL segments on polymer properties.
• To evaluate the hemocompatibility and biodegradability of the synthesized PUs.

Main Methods:

• Synthesis of multiblock copolymers using hexamethylene diisocyanate (HDI) or toluene diisocyanate (TDI).
• Characterization using NMR, GPC, DSC, TGA, XRD, and SEM.
• Assessment of hemocompatibility via platelet adhesion experiments and biodegradability through hydrolysis studies.

Main Results:

• XRD and DSC indicated mutual restriction of PHB and PCL crystallization, with PCL limiting PHB cold crystallization.
• SEM revealed hemocompatibility is influenced by polymer chain flexibility.
• Hydrolysis studies showed degradation via ester and/or urethane bond scission, affected by crystallization degree and chain configuration.

Conclusions:

• The synthesized multiblock copolymers exhibit restricted crystallization and tunable hemocompatibility.
• Biodegradability is linked to ester and urethane bond hydrolysis, influenced by polymer structure.
• These elastic, hemocompatible, and biodegradable PUs show potential for blood contact implant materials.