2011

Role of Initiator Structure on Thiol-Ene Polymerization: A Comprehensive Theoretical Study

In this study, the effects of initiator structure on thiol-ene polymerization were investigated with two initiators, four thiols, and eight monomers by utilizing the M06-2X/6-31++G(d,p) level of theory. For this purpose, a comparative investigation was carried out by modeling hydrogen abstraction from thiols (kHA) and addition reaction to monomers (ki), which is considered a side reaction. It was confirmed that the 2,2-dimethoxy-2-phenylacetophenone (DMPA) initiator is a suitable thiol-ene initiator except for the polymerization of electron-deficient or conjugated monomers. It was determined that the azobisisobutyronitrile (AIBN) initiator could not give a homogeneous thiol-ene product regardless of the monomer structure. However, it has been found that aromatic thiols should be used to obtain relatively better results with this initiator.

Keywords:

Thiol-ene polymerization, density functional theory, reaction kinetics structure-reactivity relationships,

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1. Griesbaum K. Problems and Possibilities of the Free-Radical Addition of Thiols to Unsaturated Compounds. Angew Chem Int Ed Engl. 1970 Apr;9(4):273–87.
2. Dondoni A. The Emergence of Thiol-Ene Coupling as a Click Process for Materials and Bioorganic Chemistry. Angew Chem Int Ed. 2008 Nov 10;47(47):8995–7.
3. Hoyle CE, Bowman CN. Thiol-Ene Click Chemistry. Angewandte Chemie International Edition. 2010 Feb 22;49(9):1540–73.
4. Hoyle CE, Lowe AB, Bowman CN. Thiol-click chemistry: a multifaceted toolbox for small molecule and polymer synthesis. Chem Soc Rev. 2010;39(4):1355-87.
5. Jacobine A, Fouassier J, Rabek J. Radiation curing in polymer science and technology. vol III, Elsevier (London). 1993;
6. Sun Y, Gao Y, Zhou L, Huang J, Fang H, Ma H, et al. A Study on the Electro-Optical Properties of Thiol-Ene Polymer Dispersed Cholesteric Liquid Crystal (PDChLC) Films. Molecules. 2017 Feb 22;22(2):317.
7. Heidecke CD, Lindhorst TK. Iterative Synthesis of Spacered Glycodendrons as Oligomannoside Mimetics and Evaluation of Their Antiadhesive Properties. Chem Eur J. 2007 Nov 5;13(32):9056–67.
8. Chen G, Amajjahe S, Stenzel MH. Synthesis of thiol-linked neoglycopolymers and thermo-responsive glycomicelles as potential drug carrier. Chem Commun. 2009;(10):1198-200.
9. Natali M, Begolo S, Carofiglio T, Mistura G. Rapid prototyping of multilayer thiolene microfluidic chips by photopolymerization and transfer lamination. Lab Chip. 2008;8(3):492-4.
10. Cabral JT, Hudson SD, Harrison C, Douglas JF. Frontal Photopolymerization for Microfluidic Applications. Langmuir. 2004 Nov 1;20(23):10020–9.
11. Cygan ZT, Cabral JT, Beers KL, Amis EJ. Microfluidic Platform for the Generation of Organic-Phase Microreactors. Langmuir. 2005 Apr 1;21(8):3629–34.
12. Cramer NB, Reddy SK, O’Brien AK, Bowman CN. Thiol−Ene Photopolymerization Mechanism and Rate Limiting Step Changes for Various Vinyl Functional Group Chemistries. Macromolecules. 2003 Oct 1;36(21):7964–9.
13. Zgrzeba A, Andrzejewska E, Marcinkowska A. Ionic liquid – containing ionogels by thiol–ene photopolymerization. Kinetics and solvent effect. RSC Adv. 2015;5(121):100354–61.
14. Marcinkowska A, Zgrzeba A, Lota G, Kopczyński K, Andrzejewska E. Ionogels by thiol-ene photopolymerization in ionic liquids: Formation, morphology and properties. Polymer. 2019 Jan;160:272–81.
15. Munar I, Fındık V, Degirmenci I, Aviyente V. Solvent Effects on Thiol–Ene Kinetics and Reactivity of Carbon and Sulfur Radicals. J Phys Chem A. 2020 Apr 2;124(13):2580–90.
16. Northrop BH, Coffey RN. Thiol–Ene Click Chemistry: Computational and Kinetic Analysis of the Influence of Alkene Functionality. J Am Chem Soc. 2012 Aug 22;134(33):13804–17.
17. Fındık V, Degirmenci I, Çatak Ş, Aviyente V. Theoretical investigation of thiol-ene click reactions: A DFT perspective. European Polymer Journal. 2019 Jan;110:211–20.
18. Long KF, Bongiardina NJ, Mayordomo P, Olin MJ, Ortega AD, Bowman CN. Effects of 1°, 2°, and 3° Thiols on Thiol–Ene Reactions: Polymerization Kinetics and Mechanical Behavior. Macromolecules. 2020 Jul 28;53(14):5805–15.
19. Coote ML, Degirmenci I. Theory and Applications of Thiyl Radicals in Polymer Chemistry. In: Computational Quantum Chemistry [Internet]. Elsevier; 2019 [cited 2021 Dec 29]. p. 195–218. ISBN: 978-0-12-815983-5. .
20. Hafeez S, Khatri V, Kashyap HK, Nebhani L. Computational and experimental approach to evaluate the effect of initiator concentration, solvents, and enes on the TEMPO driven thiol–ene reaction. New J Chem. 2020;44(43):18625–32.
21. Degirmenci I. Effect of Initiator Structure on Thiol‐Ene Polymerization: A DFT Study. Macromol Theory Simul. 2021 Sep;2100040.
22. Koo SPS, Stamenović MM, Prasath RA, Inglis AJ, Du Prez FE, Barner‐Kowollik C, et al. Limitations of radical thiol‐ene reactions for polymer–polymer conjugation. J Polym Sci A Polym Chem. 2010 Apr 15;48(8):1699–713.
23. Frisch M, Trucks G, Schlegel H, Scuseria G, Robb M, Cheeseman J et al. Gaussian 16 Rev. B. 01. Gaussian, Inc., Wallingford, CT; 2016.
24. Zhao Y, Truhlar DG. The M06 suite of density functionals for main group thermochemistry, thermochemical kinetics, noncovalent interactions, excited states, and transition elements: two new functionals and systematic testing of four M06-class functionals and 12 other functionals. Theor Chem Account. 2008 May;120(1–3):215–41.
25. Furuncuoğlu T, Uğur İ, Değirmenci İ, Aviyente V. Role of Chain Transfer Agents in Free Radical Polymerization Kinetics. Macromolecules. 2010 Feb 23;43(4):1823–35.
26. Truong TN, Truhlar DG. Ab initio transition state theory calculations of the reaction rate for OH+CH 4 →H 2 O+CH 3. The Journal of Chemical Physics. 1990 Aug;93(3):1761–9.
27. Duan X, Scheiner S. Energetics, proton transfer rates, and kinetic isotope effects in bent hydrogen bonds. Journal of the American Chemical Society. 1992;114(14):5849–56. ISSN: 0002-7863.
28. Griller D, Ingold KU. Persistent carbon-centered radicals. Accounts of Chemical Research. 1976;9(1):13–9. ISSN: 0001-4842.
29. Coote ML, Lin CY, Beckwith ALJ, Zavitsas AA. A comparison of methods for measuring relative radical stabilities of carbon-centred radicals. Phys Chem Chem Phys. 2010;12(33):9597.
30. Posner T. Beiträge zur Kenntniss der ungesättigten Verbindungen. II. Ueber die Addition von Mercaptanen an ungesättigte Kohlenwasserstoffe. Ber Dtsch Chem Ges. 1905;38(1):646–57.
31. Hoyle CE, Lee TY, Roper T. Thiol-enes: Chemistry of the past with promise for the future. J Polym Sci A Polym Chem. 2004 Nov 1;42(21):5301–38.
32. Chiou B-S, English RJ, Khan SA. Rheology and Photo-Cross-Linking of Thiol−Ene Polymers. Macromolecules. 1996 Jan 1;29(16):5368–74.
33. Hoyle CE, Hensel RD, Grubb MB. Temperature dependence of the laser-initiated polymerization of a thiol-ene system. J Polym Sci Polym Chem Ed. 1984 Aug;22(8):1865–73.
34. Cramer NB, Bowman CN. Kinetics of thiol-ene and thiol-acrylate photopolymerizations with real-time fourier transform infrared. J Polym Sci A Polym Chem. 2001 Oct 1;39(19):3311–9.
35. Cramer NB, Scott JP, Bowman CN. Photopolymerizations of Thiol−Ene Polymers without Photoinitiators. Macromolecules. 2002 Jul 1;35(14):5361–5.
36. Cramer NB, Davies T, O’Brien AK, Bowman CN. Mechanism and Modeling of a Thiol−Ene Photopolymerization. Macromolecules. 2003 Jun 1;36(12):4631–6.
37. Uygun M, Tasdelen MA, Yagci Y. Influence of Type of Initiation on Thiol-Ene “Click” Chemistry: Influence of Type of Initiation on Thiol-Ene “Click” Chemistry. Macromol Chem Phys. 2010 Jan 5;211(1):103–10.
38. Derboven P, D’hooge DR, Stamenovic MM, Espeel P, Marin GB, Du Prez FE, et al. Kinetic Modeling of Radical Thiol–Ene Chemistry for Macromolecular Design: Importance of Side Reactions and Diffusional Limitations. Macromolecules. 2013 Mar 12;46(5):1732–42.
39. Mucci V, Vallo C. Efficiency of 2,2-dimethoxy-2-phenylacetophenone for the photopolymerization of methacrylate monomers in thick sections. J Appl Polym Sci. 2012 Jan 5;123(1):418–25.

Journal of the Turkish Chemical Society Section A: Chemistry-Cover

Başlangıç: 2014
Yayıncı: Türkiye Kimya Derneği

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