glycolblockpolycaprolactone

Glycolblockpolycaprolactone refers to a class of biodegradable, amphiphilic block copolymers in which a glycol-containing hydrophilic block is covalently linked to hydrophobic poly(caprolactone) blocks. Typical structures include diblock and triblock forms such as PEG-b-PCL and PCL-b-PEG-b-PCL. In aqueous solution these copolymers self-assemble into micelles or nanoparticles with a PCL core and a glycol-derived corona, enabling encapsulation of hydrophobic compounds.

Synthesis generally employs ring-opening polymerization of epsilon-caprolactone using a glycol-based diol or dihydroxy-terminated polyether (for example, PEG) as initiator, with catalysts such as tin(II) octoate. By adjusting the block lengths and composition, the amphiphilicity, molecular weight, and degradation profile can be tailored.

Properties include biocompatibility and biodegradability, with hydrolytic cleavage of PCL. The hydrophilic glycol block provides solubility and steric stabilization, while the PCL block contributes hydrophobicity and mechanical strength. Degradation rate depends on crystallinity, block ratio, and environment.

Applications cover drug delivery, where they form micelles and nanoparticle carriers for hydrophobic drugs, and biomedical materials such as tissue engineering scaffolds and coatings. They are also used in cosmetic and pharmaceutical formulations as biodegradable carriers.

Characterization typically involves nuclear magnetic resonance to verify composition, gel permeation chromatography for molecular weight distribution, differential scanning calorimetry for thermal properties, and dynamic light scattering to measure assembled particle size.