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11:42
Synthesis of Monodisperse Cylindrical Nanoparticles via Crystallization-driven Self-assembly of Biodegradable Block Copolymers
Published on: June 20, 2019
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Crystallization and molecular mobility in renewable semicrystalline copolymers based on polycaprolactone and
Chaima Bouyahya1,2, Nikolaos D Bikiaris1, Alexandra Zamboulis1
1Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece. pklonos@central.ntua.gr.
Soft Matter
|November 25, 2022
Summary
Novel biodegradable block copolymers of poly(ε-caprolactone) (PCL) and poly(isosorbide) (PIS) were synthesized. The addition of amorphous PIS facilitated PCL crystallization and altered molecular mobility, indicating homogeneous PCL/PIS distribution.
Area of Science:
- Polymer Science
- Materials Science
- Organic Chemistry
Background:
- Biodegradable polymers are crucial for sustainable materials.
- Block copolymers offer tunable properties by combining different polymer segments.
- Poly(ε-caprolactone) (PCL) is a well-known semicrystalline biodegradable polyester.
- Poly(isosorbide) (PIS) is an emerging amorphous biodegradable polymer with a high glass transition temperature.
Purpose of the Study:
- To synthesize novel PCL/PIS block copolymers with varying PIS content.
- To investigate the influence of the amorphous PIS phase on the properties of semicrystalline PCL.
- To elucidate the structure-property relationships, focusing on molecular mobility and crystallization behavior.
Main Methods:
- Synthesis of PCL/PIS block copolymers via polymerization of caprolactone onto PIS.
- Characterization using differential scanning calorimetry (DSC).
- Dielectric spectroscopy.
- Polarized optical microscopy (POM).
- X-ray diffraction (XRD).
Main Results:
- PCL/PIS copolymers were successfully synthesized with controlled PCL block lengths.
- PIS addition facilitated PCL crystallization, increasing both the amount and rate of crystallization.
- The glass transition temperature (Tg) of the copolymers was primarily governed by PCL crystallinity.
- A deceleration in the PCL backbone ester group relaxation (β-relaxation) was observed in the presence of PIS.
- Moderate decreases in dielectric Tg and chain cooperativity suggested spatial confinement within PCL crystals and looser lamellar packing.
Conclusions:
- The study established a comprehensive molecular mobility map for PCL/PIS copolymers.
- The amorphous PIS phase significantly impacts the crystallization and molecular dynamics of PCL.
- The findings suggest homogeneous distribution and compatibility between PCL and PIS phases.
- These novel biodegradable block copolymers show potential for tailored material applications.
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