Skip to main content
Log in

Influence of functional group content in hydroxyl-functionalized urethane methacrylate oligomers on the crosslinking features of clearcoats

  • Published:
Journal of Coatings Technology and Research Aims and scope Submit manuscript

Abstract

Crosslinking characteristics and surface mechanical properties of radical and urethane dual-curable clearcoats were investigated by changing quantities of C=C bonds and OH groups in hydroxyl-functionalized urethane methacrylate oligomer (HFUMO) resins. The isocyanate blocked with a thermal radical initiator (BL-Tri-cHD) was utilized as a hybrid dual-curable thermal crosslinker to expedite the crosslinking of the main resin. The dual reactions between various HFUMO resins and BL-Tri-cHD were efficiently monitored via Fourier transform infrared spectroscopy to measure the peaks before and after curing. The influence of each functional group (C=C bond or OH group) in HFUMO on the initiation and development of crosslinking in dual-curable clearcoats was investigated by real-time measurements using rotational rheometer and rigid body pendulum tester. Temperature-dependent mechanical properties of cured films were confirmed through dynamic mechanical analysis. The surface mechanical properties of cured clearcoat films were also evaluated via the nanoindentation and nanoscratch tests, demonstrating the variation in surface resistance with respect to the C=C bond content and the OH value. Thus, the low-temperature curing and desired mechanical properties of clearcoats can be optimized by adjusting the content of the functional groups in a HFUMO and using a dual-curable crosslinker to simultaneously generate both radical and urethane crosslinking reactions.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7

Similar content being viewed by others

References

  1. Maier, A, Schmidt, R, Oswald-Tranta, B, Schledjewski, R, “Non-destructive Thermography Analysis of Impact Damage on Large-Scale CFRP Automotive Parts.” Materials, 7 (1) 413–429 (2014)

    Article  Google Scholar 

  2. Oldring, PKT (ed.) Chemistry and Technology of UV and EB Formulation for Coatings, Inks and Paints, Vol. 1–5. Wiley SITA Technology, London (1991)

    Google Scholar 

  3. Pappas, SP (ed.) Radiation Curing: Science and Technology (Topics in Applied Chemistry). Springer, New York (1992)

    Google Scholar 

  4. Stewart, R, “Rebounding Automotive Industry Welcome News for FRP.” Reinf. Plast., 55 (1) 38–44 (2011)

    Article  Google Scholar 

  5. Studer, K, Nesvadba, P, Jung, T, Benkhoff, J, Powell, K, Lordelot, C, “Novel Curing Agents: Thermal Radical Initiators as Viable Alternatives to Peroxides.” Prog. Org. Coat., 61 (2–4) 119–125 (2008)

    Article  CAS  Google Scholar 

  6. Studer, K, Decker, C, Beck, E, Schwalm, R, Gruber, N, “Redox and Photoinitiated Crosslinking Polymerization: I. Dual-cure Isocyanate-Acrylate System.” Prog. Org. Coat., 53 (2) 126–133 (2005)

    Article  CAS  Google Scholar 

  7. Kotoyori, T, “Critical Ignition Temperatures of Chemical Substances.” J. Loss Prev. Process Ind., 2 (1) 16–21 (1989)

    Article  Google Scholar 

  8. Seubert, C, Nietering, K, Nichols, M, Wykoff, R, Bollin, S, “An Overview of the Scratch Resistance of Automotive Coatings: Exterior Clearcoats and Polycarbonate Hardcoats.” Coatings, 2 (4) 221–234 (2012)

    Article  CAS  Google Scholar 

  9. Holbery, J, Houston, D, “Natural-Fiber-Reinforced Polymer Composites in Automotive Applications.” JOM, 58 (11) 80–86 (2006)

    Article  CAS  Google Scholar 

  10. Kotoyori, T, “The Self-accelerating Decomposition Temperature (SADT) of Solids of the Quasi-autocatalytic Decomposition Type.” J. Hazard. Mater., 64 (1) 1–19 (1999)

    Article  CAS  Google Scholar 

  11. Kim, B, Lee, DG, Kim, DY, Kim, HJ, Kong, NS, Kim, JC, Noh, SM, Jung, HW, Park, YI, “Thermal Radical Initiator Derivatives based on O-imino-isourea: Synthesis, Polymerization, and Characterization.” J. Polym. Sci. Pol. Chem., 54 (22) 3593–3600 (2016)

    Article  CAS  Google Scholar 

  12. Hwang, JW, Kim, KN, Noh, SM, Jung, HW, “The Effect of Thermal Radical Initiator derived from O-imino-isourea on Thermal Curing Characteristics and Properties of Automotive Clearcoats.” J. Coat. Technol. Res., 12 (1) 177–186 (2015)

    Article  CAS  Google Scholar 

  13. Jung, KI, Kim, B, Lee, DG, Lee, TH, Choi, SY, Kim, JC, Noh, SM, Park, YI, Jung, HW, “Characteristics of Dual-Curable Blocked Isocyanate with Thermal Radical Initiator for Low-Temperature Curing of Automotive Coatings.” Prog. Org. Coat., 125 160–166 (2018)

    Article  CAS  Google Scholar 

  14. Park, S, Hwang, JW, Kim, KN, Lee, GS, Nam, JH, Noh, SM, Jung, HW, “Rheology and Curing Characteristics of Dual-Curable Clearcoats with Hydroxyl Functionalized Urethane Methacrylate Oligomer: Effect of Blocked Isocyanate Thermal Crosslinkers.” Korea-Aust. Rheol. J., 26 (2) 159–167 (2014)

    Article  Google Scholar 

  15. Noh, SM, Lee, JW, Nam, JH, Byun, KH, Park, JM, Jung, HW, “Dual-curing Behavior and Scratch Characteristics of Hydroxyl Functionalized Urethane Methacrylate Oligomer for Automotive Clearcoats.” Prog. Org. Coat., 74 (1) 257–269 (2012)

    Article  CAS  Google Scholar 

  16. Raghavan, SR, Chen, LA, McDowell, C, Khan, SA, Hwang, R, White, S, “Rheological Study of Crosslinking and Gelation in Chlorobutyl Elastomer Systems.” Polymer, 37 (26) 5869–5875 (1996)

    Article  CAS  Google Scholar 

  17. Khan, SA, Plitz, IM, Frantz, RA, “In Situ Technique for Monitoring the Gelation of UV Curable Polymers.” Rheol. Acta, 31 (2) 151–160 (1992)

    Article  CAS  Google Scholar 

  18. Chiou, BS, Raghavan, SR, Khan, SA, “Effect of Colloidal Fillers on the Cross-Linking of a UV-Curable Polymer: Gel Point Rheology and the Winter-Chambon Criterion.” Macromolecules, 34 (13) 4526–4533 (2001)

    Article  CAS  Google Scholar 

  19. Zhang, Y, Yang, X, Zhao, X, Huang, W, “Synthesis and Properties of Optically Clear Silicone Resin/Epoxy Resin Hybrids.” Polym. Int., 61 (2) 294–300 (2012)

    Article  CAS  Google Scholar 

  20. Noh, SM, Lee, JW, Nam, JH, Park, JM, Jung, HW, “Analysis of Scratch Characteristics of Automotive Clearcoats Containing Silane Modified Blocked Isocyanates via Carwash and Nano-scratch Tests.” Prog. Org. Coat., 74 (1) 192–203 (2012)

    Article  CAS  Google Scholar 

  21. Chiu, HT, Wu, JH, “A Study on the Curing Behavior of Silicone/Polyurethane/Epoxy Blends by Rigid-Body Pendulum Rheometer.” Polym.-Plast. Technol. Eng., 45 (9) 1081–1085 (2006)

    Article  CAS  Google Scholar 

  22. Chiu, HT, Wu, JH, “Silicone/Polypropylene Oxide-Polyethylene Oxide Copolymer/Clay Composites (i) - Curing Behavior, Intermolecular Interaction and Thermomechanical Properties.” J. Polym. Res., 11 (4) 247–255 (2005)

    Article  Google Scholar 

  23. Chiu, HT, Cheng, JO, “Thermal Imidization Behavior of Aromatic Polyimides by Rigid-Body Pendulum Rheometer.” J. Appl. Polym. Sci., 108 (6) 3973–3981 (2008)

    Article  CAS  Google Scholar 

  24. Rath, SK, Bahadur, J, Panda, HS, Sen, D, Patro, TU, Praveen, S, Patri, M, Khakhar, DV, “Anomalous Toluene Transport in Model Segmented Polyurethane–Urea/Clay Nanocomposites.” Soft Matter, 14 (19) 3870–3881 (2018)

    Article  CAS  Google Scholar 

  25. Das, A, Mahaling, RN, Stöckelhuber, KW, Heinrich, G, “Reinforcement and Migration of Nanoclay in Polychloroprene/Ethylene–Propylene–Diene-Monomer Rubber Blends.” Compos. Sci. Technol., 71 (3) 276–281 (2011)

    Article  CAS  Google Scholar 

  26. Briscoe, BJ, Fiori, L, Pelillo, E, “Nano-indentation of Polymeric Surfaces.” J. Phys. D- Appl. Phys., 31 (19) 2395 (1998)

    Article  CAS  Google Scholar 

  27. Tahmassebi, N, Moradian, S, Ramezanzadeh, B, Khosravi, A, Behdad, S, “Effect of Addition of Hydrophobic Nano Silica on Viscoelastic Properties and Scratch Resistance of an Acrylic/Melamine Automotive Clearcoat.” Tribol. Int., 43 (3) 685–693 (2010)

    Article  CAS  Google Scholar 

  28. Pharr, GM, Oliver, WC, Brotzen, FR, “On the Generality of the Relationship Among Contact Stiffness, Contact Area, and Elastic Modulus During Indentation.” J. Mater. Res., 7 (3) 613–617 (1992)

    Article  CAS  Google Scholar 

  29. Oliver, WC, Pharr, GM, “An Improved Technique for Determining Hardness and Elastic Modulus Using Load and Displacement Sensing Indentation Experiments.” J. Mater. Res., 7 (6) 1564–1583 (1992)

    Article  CAS  Google Scholar 

  30. Ngan, AHW, Wang, HT, Tang, B, Sze, KY, “Correcting Power-law Viscoelastic Effects in Elastic Modulus Measurement Using Depth-sensing Indentation.” Int. J. Solids Struct., 42 (5–6) 1831–1846 (2005)

    Article  Google Scholar 

  31. Decker, C, Lorinczova, I, “UV-radiation Curing of Waterborne Acrylate Coatings.” JCT Res., 1 (4) 247–256 (2004)

    CAS  Google Scholar 

Download references

Acknowledgments

This study was supported by research grants from the Ministry of Trade, Industry & Energy (MOTIE, Korea) under the Industrial Technology Innovation Program (Nos. 10067706, 20010256).

Author information

Authors and Affiliations

Authors

Corresponding authors

Correspondence to Seung Man Noh or Hyun Wook Jung.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

June, YG., Jung, K.I., Lee, D.G. et al. Influence of functional group content in hydroxyl-functionalized urethane methacrylate oligomers on the crosslinking features of clearcoats. J Coat Technol Res 18, 229–237 (2021). https://doi.org/10.1007/s11998-020-00398-1

Download citation

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11998-020-00398-1

Keywords

Navigation