Metal‐free synthesis of novel biobased dihydroxyl‐terminated aliphatic polyesters as building blocks for thermoplastic polyurethanes

Abstract

Using the organic compound 1,5,7‐triazabicyclo[4.4.0]dec‐5‐ene (TBD) as a catalyst for step‐growth polymerization, a series of well‐defined hydroxyl‐telechelic renewable aliphatic polyesters (including poly(1,3‐propylene adipate); poly(1,4‐butylene adipate); poly(1,12‐dodecylene sebacate); and poly(1,2‐dimethylethylene adipate), PDMEA) were synthesized and studied. PDMEA is a novel polyester, which has not been reported before. The results of 1H NMR and Matrix‐assisted laser desorption ionization time‐of‐flight mass spectrometry indicate that the polymers are fully hydroxyl terminated. From differential scanning calorimetry (DSC) thermograms, we found that the glass transition temperatures (Tg) of these polyesters are below −20 °C. Only a Tg but no melting peak is observed in the DSC curve of the novel PDMEA. This indicates that PDMEA, contrary to the other renewable polyesters, is totally amorphous. Furthermore, using hexamethylene diisocyanate and hexamethylene diamine, poly(ester urethane urea)s (PEUUs) based on PDMEA were successfully synthesized. The Tg of the prepared PEUUs is below 0 °C, and no melting behavior of the soft‐segment is observed. The PEUU, with a flow temperature of over 200 °C, thus behaves as an elastomer at room temperature. Its mechanical properties, such as a relatively low tensile E‐modulus (≈20 MPa) at room temperature and a sufficiently high strain at break (≈560%), make it suitable for use in, for example, biomedical applications. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011

Thermoplastic Poly(urethane urea)s From Novel, Bio‐based Amorphous Polyester Diols

“…The results are shown in Figure 1 and Table 2, from which it is observed that all the TPUUs exhibit similar degradation behavior as a function of the temperature, with the exception of 4U PDMES and 3U PDMES . These two PDMES‐based polymers are less stable than the other polymers, which fits the trend of the relatively poor thermal stability of PDMES described previously 19. As shown in Table 2, the thermal stability of the TPUUs doesnot significantly depend on the different lengths of the HSs.…”

“…The polyester diols, including poly(1,4‐butylene adipate) (PBA), poly(1,2‐dimethylethylene adipate) (PDMEA) and poly(1,2‐dimethylethylene succinate) (PDMES), were prepared in house (details of their preparation are described in a previous publication19 and their molecular weights are given in Table 1). Poly(1,2‐propylene glycol) (PPG, M n = 725 g mol −1 ), hexamethylene diisocyanate (HDI, > 99.0%), 1,6‐diaminohexane (DAH, 98%), dibutyltin dilaurate (DBTDL), phosphate‐buffered saline (PBS, pH 7.4), and pseudomonas cepacia Lipase (Lipase PS) were purchased from Sigma–Aldrich.…”

“…Bio‐based polyesters are also used more and more 16–18. In this study, the novel, bio‐based, fully amorphous aliphatic polyesters poly(1,2‐dimethylethylene adipate) (PDMEA) and poly(1,2‐dimethylethylene succinate) (PDMES), prepared as described previously,19 are applied as the PDs for TPU synthesis. The other PDs, such as the semicrystalline polyester poly(1,4‐butylene adipate) (PBA) and the non‐degradable, amorphous polyether poly(1,2‐propylene glycol) (PPG), are used as comparisons to the two amorphous polyesters mentioned above.…”

Vegetable oils: a source of polyols for polyurethane materials

“…Using this strategy, Koning and coll. have prepared partially fatty acidbased aliphatic polyester diols from dimethyl sebacate using TBD as a catalyst (Tang et al, 2011). Moreover, Corcuera and coll.…”

Multi-Block Polyurethanes via RAFT End-Group Switching and Their Characterization by Advanced Hyphenated Techniques

“…A pTHF to diisocyanate ratio of 2 to 3 was chosen to obtain a doubling in molecular weight. 28 The prepolymer was analyzed via SEC and the isocyanate content was determined via titration. The SEC trace of the prepolymer, confirming the increase in molar mass, is presented in Figure S1 of the Supporting Information section and is compared with the SEC elugram of the initial pTHF.…”