Hostname: page-component-cd9895bd7-mkpzs Total loading time: 0 Render date: 2024-12-27T12:12:32.287Z Has data issue: false hasContentIssue false

High-Throughput Synthesis of Oligo(ε-caprolactone) / Oligotetrahydrofuran Based Polyurethanes

Published online by Cambridge University Press:  05 April 2018

M. Balk
Affiliation:
Institute of Biomaterial Science, Helmholtz-Zentrum Geesthacht, Teltow, Germany
A. Lendlein
Affiliation:
Institute of Biomaterial Science, Helmholtz-Zentrum Geesthacht, Teltow, Germany
M. Behl*
Affiliation:
Institute of Biomaterial Science, Helmholtz-Zentrum Geesthacht, Teltow, Germany
*
*Correspondence to: Dr. Marc Behl Institute of Biomaterial Science, Helmholtz-Zentrum Geesthacht, Kantstr. 55, 14513, Teltow, Germany Email: marc.behl@hzg.de Phone: +49 (0)3328 352-229 Fax: +49 (0)3328 352-452
Get access

Abstract

Robot assisted synthesis as part of high-throughput (HT) technology can assist in the creation of polymer libraries, e.g. polymers with a variety of molecular weights, by automatizing similar reactions. Especially for multiblock copolymers like polyurethanes (PUs) synthesized from telechels via polyaddition reaction, the adjustment of equivalent molar amounts of reactants requires a comprehensive investigation of end group functionality.

In this work, PUs based on oligo(ε-caprolactone) (OCL) / oligotetrahydrofuran (OTHF) as model components were designed utilizing HT synthesis enabling the quantitative determination of the optimized ratio between reactive end-groups via fully automated syntheses without major characterization effort of end group functionality. The semi-crystalline oligomeric telechelics were connected with a diisocyanate and OCL with a molecular weight of 2, 4, or 8 kg∙mol-1 was integrated. Here, optimized molecular weights between 90 ± 10 kg∙mol-1 (in case of OCL 8 kg∙mol-1) and 260 ± 30 kg∙mol-1 (in case of OCL 2 kg∙mol-1) were obtained with an isocyanate content of 120 mol%, whereby 100 mol% of isocyanate groups resulted only in molecular weights between 60 ± 6 kg∙mol-1 (OCL 8 kg∙mol-1) and 80 ± 10 kg∙mol-1 (OCL 2 kg∙mol-1). In addition to the optimized ratio between isocyanate and hydroxy end groups, quantitative influences of the OCL chain length and overall molecular weights of PUs on thermal and mechanical properties were detected. The melting temperatures (Tms) of OCL and OTHF domains were well separated for PUs of low molecular weight, the temperature interval between the Tms decreased when the molecular weight of the PUs was increased, and were even overlapping towards one broad Tm, when OCL 2 kg∙mol-1 was incorporated. The storage modulus E’ was highly dependent on OCL chain length exhibiting an increase with increasing molecular weight of OCL from 220 MPa to 440 MPa at 0 °C and decreased with increasing chain length of PUs. The elongation at break (εb) was analyzed below and above Tm of OTHF resulting in εb = 780-870% at 0 °C and εb = 510-830% at 30 °C for PUs of high molecular weight. Accordingly, stretchability of PUs was almost independent of the state of OTHF (semi crystalline or amorphous) but correlated with the OCL precursor chain length (increasing εb with increasing chain length) and overall molecular weight of PUs (PUs at higher molecular weight exhibited higher εb). Hence, the analysis of these quantitative influences between macromolecular structure of multiblock copolymers and the resulting properties (well separated Tms versus overlapping melting transition, improvement of stretchability) would enable the design of new tailored PUs.

Type
Articles
Copyright
Copyright © Materials Research Society 2018 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Rojas, R., Harris, N. K., Piotrowska, K. and Kohn, J., J. Polym. Sci. Part A: Polym. Chem. 47 (1), 49-58 (2009).CrossRefGoogle Scholar
Lewitus, D., Rios, F., Rojas, R. and Kohn, J., J. Mater. Scie. Mater. Med. 24 (11), 10.1007/s10856-10013-15008-10850 (2013).Google Scholar
Majoros, L. I., Dekeyser, B., Hoogenboom, R., Fijten, M. W. M., Haucourt, N. and Schubert, U. S., J. Polym. Sci. Part A: Polym. Chem. 47 (15), 3729-3739 (2009).CrossRefGoogle Scholar
Krska, S. W., DiRocco, D. A., Dreher, S. D. and Shevlin, M., Acc. Chem. Res. 50 (12), 2976-2985 (2017).CrossRefGoogle Scholar
Çakir, S., Bauters, E., Rivero, G., Parasote, T., Paul, J. and Du Prez, F. E., ACS Comb. Sci. 19 (7), 447-454 (2017).CrossRefGoogle Scholar
Ballard, N., Aguirre, M., Simula, A., Leiza, J. R., van Es, S. and Asua, J. M., Polym. Chem. 8 (10), 1628-1635 (2017).CrossRefGoogle Scholar
Willhammar, T., Su, J., Yun, Y., Zou, X., Afeworki, M., Weston, S. C., Vroman, H. B., Lonergan, W. W. and Strohmaier, K. G., Inorg. Chem. 56 (15), 8856-8864 (2017).CrossRefGoogle Scholar
Flory, P. J., J. Am. Chem. Soc. 58 (10), 1877-1885 (1936).CrossRefGoogle Scholar
Flory, P. J., Principles of Polymer Chemistry. (Cornell University Press, Ithaca, 1969).Google Scholar
Raspoet, G., Nguyen, M. T., McGarraghy, M. and Hegarty, A. F., J. Org. Chem. 63 (20), 6867-6877 (1998).CrossRefGoogle Scholar
Zheng, L., Li, C., Zhang, D., Guan, G., Xiao, Y. and Wang, D., Polym. Degrad. Stab. 95 (9), 1743-1750 (2010).CrossRefGoogle Scholar
Stepto, R. F. T. and Waywell, D. R., Macromol Chem. Phys. 152 (1), 263-275 (1972).CrossRefGoogle Scholar
Flory, P. J., Chem. Rev. 39 (1), 137-197 (1946).CrossRefGoogle Scholar
Gorna, K., Polowinski, S. and Gogolewski, S., J. Polym. Sci. Part A: Polym. Chem 40 (1), 156-170 (2002).CrossRefGoogle Scholar
Lendlein, A., Neuenschwander, P. and Suter, U. W., Macromol. Chem. Phys. 199 (12), 2785-2796 (1998).3.0.CO;2-X>CrossRefGoogle Scholar
Lendlein, A., Schmidt, A. M., Schroeter, M. and Langer, R., J. Polym. Sci., Part A: Polym. Chem. 43 (7), 1369-1381 (2005).CrossRefGoogle Scholar
McKiernan, R. L., Heintz, A. M., Hsu, S. L., Atkins, E. D. T., Penelle, J. and Gido, S. P., Macromolecules 35 (18), 6970-6974 (2002).CrossRefGoogle Scholar
Yilgör, E., Yurtsever, E. and Yilgör, I., Polymer 43 (24), 6561-6568 (2002).CrossRefGoogle Scholar
Cohn, D. and Hotovely Salomon, A., Biomaterials 26 (15), 2297-2305 (2005).CrossRefGoogle Scholar
Kim, B. K., Shin, Y. J., Cho, S. M. and Jeong, H. M., J. Polym. Sci. Part B: Polym. Phys. 38 (20), 2652-2657 (2000).3.0.CO;2-3>CrossRefGoogle Scholar
Feng, Y., Behl, M., Kelch, S. and Lendlein, A., Macromol. Biosci. 9 (1), 45-54 (2009).CrossRefGoogle Scholar