Abstract
The transesterification of poly(L-lactic acid) (PLA) with 0.05 M and 0.10 M of tin(II) octoate (Sn(Oct)2), aluminum(III) tri-sec-butoxide (Al(OsBu)3) and titanium(IV) n-butoxide (Ti(OnBu)4) catalysts in CHCl3 was successfully investigated by gel permeation chromatography (GPC) and proton-nuclear magnetic resonance spectroscopy (1H-NMR) techniques. All catalysts were completely and rapidly dissolved in PLA solution. When intramolecular transesterification reaction occurred, the physical appearances of PLA were changed from longer fiber to shorter fiber or power due to the decreasing of molecular weight and chain scission. The transesterification reaction of PLA depended on catalyst concentration, reaction time and catalyst type. From kinetics study, the transesterification of PLA with all catalysts was the first order reaction. The molecular weight of PLA decreased faster at higher catalyst concentration. At identical catalyst concentration, the molecular weight of PLA obtained from transesterification time of 1 d was higher than 2, 3 and 4 d, respectively. The molecular weight of PLA in the presence of Sn(Oct)2 dramatically decreased to 7.33 × 103 g/mol at 4 d when compared with PLA in the absence of Sn(Oct)2 (6.78 × 104 g/mol). From GPC technique, the apparent rate constants of transesterification (kapp) of PLA with 0.10 M of Sn(Oct)2, Ti(OnBu)4 and Al(OsBu)3 were 0.283, 0.085 and 0.073 d−1, respectively. From 1H-NMR technique, the kapp values of PLA with 0.10 M of Sn(Oct)2, Ti(OnBu)4 and Al(OsBu)3 were 0.297, 0.192 and 0.151 d−1, respectively. The lowest apparent half-life (t1/2,app) obtained from the 1H-NMR technique for PLA transesterification with Sn(Oct)2, Ti(OnBu)4 and Al(OsBu)3 was 2.333, 3.610 and 4.589 d, respectively. The transesterification activity of Sn(II), Al(III) and Ti(IV) catalysts for PLA was determined in the following order: Sn(Oct)2 > Ti(OnBu)4 > Al(OsBu)3. From kinetics and mechanistic studies, the transesterification of PLA with these Sn(II), Al(III) and Ti(IV) catalysts was proposed through the intramolecular transesterification.
Graphical abstract
Similar content being viewed by others
References
Hamad K, Kaseem M, Yang HW, Deri F, Ko YG (2015) Properties and medical applications of polylactic acid: a review. Express Polym Lett 9:435–455
Tian H, Tang Z, Zhuang X, Chen X, Jing X (2012) Biodegradable synthetic polymers: preparation, functionalization and biomedical application. Prog Polym Sci 37:237–280
Jin X, Cui S, Sun S, Sun J, Zhang S (2021) The preparation and characterization of polylactic acid composites with chitin-based intumescent flame retardants. Polymers 13:3513
Thomas MS, Pillai PKS, Faria M, Cordeiro N, Kailas L, Kalarikkal N, Thomas S, Pothen LA (2020) Polylactic acid/nano-chitosan composite fibers and their morphological, physical characterization for the removal of cadmium(II) from water. J App Polym Sci 137:48993
Girdthep S, Limwanich W, Punyodom W (2022) Non-isothermal cold crystallization, melting, and moisture barrier properties of silver-loaded kaolinite filled poly(lactic acid) films. Mater Chem Phys 276:125227
Albertsson AC, Varma IK (2003) Recent developments in ring opening polymerization of lactones for biomedical applications. Biomacromol 4:1466–1486
Stridsberg KM, Ryner M, Albertsson AC (2002) Controlled ring-opening polymerization: polymers with designed macromolecular architecture. Adv Polym Sci 157:41–65
Sobczak M (2012) Ring-opening polymerization of cyclic esters in the presences of choline/SnOct2 catalytic system. Polym Bull 68:2219–2228
Kricheldorf HR, Weidner SM, Scheliga F (2007) Cyclic poly(L-lactide) via ring-expansion polymerization by means of dibutyltin 4-tret-butylcatecholate. Macromol Chem Phys 218:1700274
Deivasagayam D, Peruch F (2011) Titanium complexes based on aminodiol ligands for the ring opening polymerization of L- and D, L-lactide. Polymer 52:4686–4693
Bandelli D, Weber C, Schubert US (2019) Strontium isopropoxide: a highly active catalysts for the ring-opening polymerization of lactide and various lactones. Macromol Rapid Commun 40:1900306
Chmura AJ, Cousins DM, Davidson MG, Jones MD, Lunn MD, Nahon MF (2008) Robust chiral zirconium alkoxide initiators for the room-temperature stereoselective ring-opening polymerization of rac-lactide. Dalton Trans 11:1437–1443
Kowalski A, Libiszowski J, Duda A, Penczek S (2000) Polymerization of L, L-dilactide initiated by tin(II) butoxide. Macromolecules 33:1964–1971
Limwanich W, Meepowpan P, Sriyai M, Chainwon T, Punyodom W (2020) Eco-friendly synthesis of biodegradable poly(ε-caprolactone) using L-lactic and glycolic acids as organic initiator. Polym Bull. https://doi.org/10.1007/s00289-020-03401-2
Kricheldorf HR, Berl M, Scharnagl N (1988) Poly(lactones). 9. Polymerization mechanism of metal alkoxide initiated polymerizations of lactide and various lactones. Macromolecules 21:286–293
Weidner SM, Kricheldorf HR (2017) The role of transesterification in Sn(Oct)2-catalyzed polymerizations of lactides. Macromol Chem Phys 218:1600331
Weidner SM, Kricheldorf HR (2017) Transesterification in the solid state of cyclic and linear poly(L-lactide)s. Macromol Chem Phys 218:1700114
Leibfarth FA, Moreno N, Hawker AP, Shand JD (2012) Transforming polylactides into value-added materials. J Polym Sci Part A Polym Chem 50:4814–4822
Limwanich W, Punyodom W, Kungwan N, Meepowpan P (2015) DSC kinetics analysis for the synthesis of three-arms poly(caprolactone) using aluminum tri-sec-butoxide as initiator, opening polymerization of ε-caprolactone: Kinetics studies by non-isothermal DSC. Inter J Chem Kinet 47:734–743
Meelua W, Molloy R, Meepowpan P, Punyodom W (2012) Isoconversional kinetic analysis of ring-opening polymerization of ε-caprolactone: steric influence of titanium(IV) alkoxides as initiators. J Polym Res 19:9799
Punyodom W, Limwanich W, Meepowpan P (2017) Tin(II) n-butyl L-lactate as novel initiator for the ring-opening polymerization of ε-caprolactone: kinetics and aggregation equilibrium analysis by non-isothermal DSC. Thermochim Acta 655:337–343
Limwanich W, Meepowpan P, Kungwan N, Punyodom W (2020) Influence of butyl group of tin chloride initiators on the non-isothermal DSC ring-opening polymerization of ε-caprolactone: the studies of kinetics, mechanism and polymer synthesis. Thermochim Acta 683:178458
Hamza AA, Sokkar TZN, El-Bakary MA, Ali AM (2010) On line interferometric investigation of the neck propagation phenomena of stretched polypropylene fibre. Opt Laser Technol 42(5):403–709
Bero M, Czapla B, Dobrzynski P, Janeczek H, Kasperczyk J (1999) Copolymerization of glycolide and ε-caprolactone. Macromol Chem Phys 200:911–916
Cabaret OD, Vaca BM, Bourissor D (2004) Controlled ring-opening polymerization of lactide and glycolide. Chem Rev 104:6147–6176
Kricheldorf HR, Weidner SM (2020) High molar mass cyclic poly(L-lactide) obtained by means of neat tin(II) 2-ethylhexanoate. Polym Chem 11:5249–5260
Kricheldorf HR, Weidner SM (2019) SnOct2-catalyzed syntheses of cyclic poly(L-lactide)s with catechol as low-toxic co-catalyst. J Polym Environ 27:2697–2706
Martin RL, Winter G (1960) Structure of the trinuclear titanium(IV) alkxoides. Nature 188:313–315
Acknowledgements
The authors wish to thank the financial supports from Center of Excellence in Materials Science and Technology, Chiang Mai University (WP, PM), the Thailand Research Fund (TRF) (MRG6080164) (WL) and Office of the Higher Education Commission (OHEC) (WL). The Department of Chemistry and Materials Science Research Center, Faculty of Science, Chiang Mai University, Faculty of Sciences and Agricultural Technology, Rajamangala University of Technology Lanna and Department of Chemistry, Faculty of Science, Silpakorn University are also acknowledged.
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
Conflict of interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
About this article
Cite this article
Punyodom, W., Meepowpan, P., Girdthep, S. et al. Influence of tin(II), aluminum(III) and titanium(IV) catalysts on the transesterification of poly(L-lactic acid). Polym. Bull. 79, 11409–11429 (2022). https://doi.org/10.1007/s00289-021-04005-0
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00289-021-04005-0