Hydrophilic Poly(ether-ester)s and Poly(ether-ester-amide)s Derived from Poly(ε-caprolactone) and COCl Terminated PEG Macromers

• Published in: Macromolecular bioscience 2003-12, Vol.3 (12), p.749-757
• Main Authors: Crisci, Leonilda, Volpe, Claudio Della, Maglio, Giovanni, Nese, Giuseppe, Palumbo, Rosario, Rachiero, Giovanni P., Vignola, Maria C.
• Format: Article
• Language: English
• Subjects: Applied sciences; block copolymers; Exact sciences and technology; hydrophilic polymers; Organic polymers; Physicochemistry of polymers; poly(ester-amide)s; poly(ether-ester-amide)s; poly(ε-caprolactone); Polycondensation; Preparation, kinetics, thermodynamics, mechanism and catalysts
• ISSN: 1616-5187; 1616-5195
• DOI: 10.1002/mabi.200300025

A series of poly(ε‐caprolactone) (PCL)‐based multiblock poly(ether‐ester)s (PEE)s and poly(ether‐ester‐amide)s (PEEA)s were obtained from α,ω‐dihydroxy‐PCL ($\overline M _{\rm n}$ = 2–4 kDa) and COCl di‐terminated poly(ethylene oxide) (PEO) macromers (MAC) of different length ($\overline M _{\rm n}$ = 150, 300, 600, 1 000 Da). 4,7,10‐Trioxa‐1,13‐tridecanediamine was used in the synthesis of PEEAs. Bulk polycondensation processes were accomplished by one step (PEE) and two step (PEEA) procedures. PEEAs with PCL/MAC/Trioxy molar ratios 1:2:1 and 1:3:2 were investigated. The multiblock copolymer architecture was proved by 1H NMR and size exclusion chromatography (SEC) techniques. Unimodal molecular weight (MW) distributions and $\overline M _{\rm n}$ values in the range of 13.3–21.0 kDa (PEE) and 8.1–12.8 kDa (PEEA) were found. Crystalline PCL‐type phases were identified for both PEEAs and PEEs by X‐ray diffraction. The thermal transitions were investigated by differential scanning calorimetry (DSC). The Tm values (49.9–53.4 °C) reflect those of the PCL component while the Tg of PEEAs (−45 to −52 °C) are higher than those of the PEEs (−58 to −61 °C) or the macromers. The equilibrium water uptakes range from 1.0 to 18.4 wt.‐% (PEE) and from 4.4 to 8.8 wt.‐% (PEEA) depending on both the composition and length of the ethylene oxide sequences. A dependence of surface homogeneity on copolymer composition was found for PEEs by dynamic contact angle measurements. The preparation of PEEAs and PEEs.