, Volume 79, Issue 15–16, pp 977–984 | Cite as

Supercritical Fluid Chromatography with Evaporative Light Scattering Detection (SFC-ELSD) for Determination of Oligomer Molecular Weight Distributions

  • Justin M. Sirrine
  • Mehdi Ashraf-Khorassani
  • Nicholas G. Moon
  • Ryan J. Mondschein
  • Timothy E. Long
Short Communication
Part of the following topical collections:
  1. 2015 International Symposium on GPC/SEC and Related Techniques


Ultraviolet curable polyureas and polyurethanes enjoy a wide range of applications in the coatings industry. They demand less energy for curing compared to thermal processes that offer relatively low viscosities before photocuring, and provide mechanical property improvements due to hydrogen bonding physical crosslinks. Mechanical properties of the coatings are dependent on a variety of factors, including chemical composition, molecular weight, and molecular weight distribution. Formulations are designed for a wide variety of end use applications, ranging from soft, elastomeric coatings to harder, nonflexible sealants. This report demonstrates that the thermomechanical behavior of photocured coatings is a function of molecular weight distribution. Step-growth polymerization and endcapping afforded a variety of acrylate-terminated, urea-/urethane-containing photocurable oligomers from amine-terminated poly(propylene glycol), dicyclohexylmethane-4,4′-diisocyanate (HMDI), and 2-hydroxyethyl acrylate (HEA) at various stoichiometric ratios. The state-of-the-art supercritical fluid chromatography coupled with evaporative light-scattering detection (SFC-ELSD) enabled the elucidation of oligomeric molecular weight distributions as a function of reaction stoichiometry. SFC-ELSD demonstrated the efficient separation of oligomeric species with single repeat unit resolution (i.e., n = 2 vs. n = 3). Dynamic mechanical analysis probed thermomechanical response of photocured films as a function of molecular weight distribution and demonstrated that the presence of a hydrogen-bonding, small molecule photoactive reaction byproduct, i.e., HEA doubly-endcapped HMDI, had a much more profound effect on thermomechanical response as compared to changes in oligomer molecular weight in the molecular weight range investigated. This combination of chromatographic technique and thermomechanical analysis afforded an in-depth investigation of the structure–property relationships of urea-/urethane-containing photocurable oligomers.


Supercritical fluid chromatography (SFC) Evaporative light-scattering detection (ELSD) Dynamic mechanical analysis (DMA) Photocurable Photopolymer Coatings 



The authors acknowledge Bayer MaterialScience (now Covestro) for providing HMDI. The authors also acknowledge TA Instruments-Waters LLC for loaning the Aquity UPC2 SFC-ELSD system.

Compliance with Ethical Standards

Conflicts of interest

The authors declare no conflicts of interest.

Human participant or animals

This article does not contain any studies with human participants or animals performed by any of the authors.

Supplementary material

10337_2016_3098_MOESM1_ESM.pdf (758 kb)
The materials and methods section, a table of theoretical and experimental number-average molecular weights (Mn) of SFC-ELSD samples, a table of theoretical number-average molecular weights (Mn) of various expected species in SFC-ELSD chromatograms, and 1H NMR molecular structure confirmation of a dialyzed 1.0 : 3.0 : 5.0 oligomer are provided, as well as additional SFC-ELSD chromatograms for additional samples, including D* and HEA alone. This information is available on the Journal’s website (PDF 758 kb)


  1. 1.
    Raynor MW, Bartle KD (1993) Supercritical fluid chromatography and extraction in surface coatings analysis—review of representative applicationst. J Supercrit Fluids 6(1):39–49CrossRefGoogle Scholar
  2. 2.
    Levy N (1982) Low Tg soft UV-curable coatings. U.S. 4324575 AGoogle Scholar
  3. 3.
    Cashion MP, Park T, Long TE (2009) Influence of hydrogen bonding on the adhesive properties of photo-curable acrylics. J Adhes 85(1):1–17CrossRefGoogle Scholar
  4. 4.
    Sirrine JM, Pekkanen AM, Nelson AM, Chartrain NA, Williams CB, Long TE (2015) 3D-printable biodegradable polyester tissue scaffolds for cell adhesion. Aust J Chem 68(9):1409–1414CrossRefGoogle Scholar
  5. 5.
    Lee JW, Kang KS, Lee SH, Kim J-Y, Lee B-K, Cho D-W (2011) Bone regeneration using a microstereolithography-produced customized poly(propylene fumarate)/diethyl fumarate photopolymer 3D scaffold incorporating BMP-2 loaded PLGA microspheres. Biomaterials 32(3):744–752CrossRefGoogle Scholar
  6. 6.
    Karikari AS, Edwards WF, Mecham JB, Long TE (2005) Influence of peripheral hydrogen bonding on the mechanical properties of photo-cross-linked star-shaped poly(d, l-lactide) networks. Biomacromolecules 6(5):2866–2874CrossRefGoogle Scholar
  7. 7.
    Gupta P, Trenor SR, Long TE, Wilkes GL (2004) In situ photo-cross-linking of cinnamate functionalized poly(methyl methacrylate-co-2-hydroxyethyl acrylate) fibers during electrospinning. Macromolecules 37(24):9211–9218CrossRefGoogle Scholar
  8. 8.
    Swiderski KW, Khudyakov IV (2004) Synthesis and properties of urethane acrylate oligomers: direct versus reverse addition. Ind Eng Chem Res 43(20):6281–6284CrossRefGoogle Scholar
  9. 9.
    Temenoff JS, Athanasiou KA, Lebaron RG, Mikos AG (2002) Effect of poly (ethylene glycol) molecular weight on tensile and swelling properties of oligo (poly (ethylene glycol) fumarate) hydrogels for cartilage tissue engineering. J Biomed Mater Res 59(3):429–437CrossRefGoogle Scholar
  10. 10.
    Schou-Pedersen AMV, Østergaard J, Johansson M, Dubant S, Frederiksen RB, Hansen SH (2014) Evaluation of supercritical fluid chromatography for testing of PEG adducts in pharmaceuticals. J Pharm Biomed Anal 88:256–261CrossRefGoogle Scholar
  11. 11.
    Hoffman BJ, Taylor LT, Rumbelow S, Goff L, Pinkston JD (2004) Separation of derivatized alcohol ethoxylates and propoxylates by low temperature packed column supercritical fluid chromatography using ultraviolet absorbance detection. J Chromatogr A 1034(1–2):207–212CrossRefGoogle Scholar
  12. 12.
    Pinkston JD, Delaney TE, Bowling DJ (1990) Characterization of low molecular weight poly(acrylic acid) samples by capillary supercritical fluid chromatography and capillary supercritical fluid chromatography–mass spectrometry. J Microcolumn Sep 2(4):181–187CrossRefGoogle Scholar
  13. 13.
    Carrott M, Davidson G (1999) Separation and characterisation of phenol-formaldehyde (resol) prepolymers using packed-column supercritical fluid chromatography with APCI mass spectrometric detection. Analyst 124(7):993–997CrossRefGoogle Scholar
  14. 14.
    Ute K (1997) Fractionation of polymer homologs with packed column supercritical fluid chromatography. In: Supercritical fluid chromatography with packed column. Chromatographic Science Series, vol 75. pp 349–368Google Scholar
  15. 15.
    Pinkston JD, Marapane SB, Jordan GT, Clair BD (2002) Characterization of low molecular weight alkoxylated polymers using long column SFC/MS and an image analysis based quantitation approach. J Am Soc Mass Spectrom 13(10):1195–1208CrossRefGoogle Scholar
  16. 16.
    Yip H, Ashraf-Khorassani M, Taylor L (2007) Feasibility of phospholipids separation by packed column SFC with mass spectrometric and light scattering detection. Chromatographia 65(11–12):655–665CrossRefGoogle Scholar
  17. 17.
    Bartle KD, Boddington T, Clifford AA, Cotton NJ, Dowle CJ (1991) Supercritical fluid extraction and chromatography for the determination of oligomers in poly(ethylene terephthalate) films. Anal Chem 63(20):2371–2377CrossRefGoogle Scholar
  18. 18.
    Takahashi K (2013) Polymer analysis by supercritical fluid chromatography. J Biosci Bioeng 116(2):133–140CrossRefGoogle Scholar
  19. 19.
    Pretorius NO, Willemse CM, de Villiers A, Pasch H (2014) Combined size exclusion chromatography, supercritical fluid chromatography and electrospray ionization mass spectrometry for the analysis of complex aliphatic polyesters. J Chromatogr A 1330:74–81CrossRefGoogle Scholar
  20. 20.
    Lesellier E, Valarché A, West C, Dreux M (2012) Effects of selected parameters on the response of the evaporative light scattering detector in supercritical fluid chromatography. J Chromatogr A 1250:220–226CrossRefGoogle Scholar
  21. 21.
    Lecoeur M, Simon N, Sautou V, Decaudin B, Vaccher C, group As (2014) A chemometric approach to elucidate the parameter impact in the hyphenation of evaporative light scattering detector to supercritical fluid chromatography. J Chromatogr A 1333:124–133CrossRefGoogle Scholar
  22. 22.
    Chattopadhyay DK, Panda SS, Raju KVSN (2005) Thermal and mechanical properties of epoxy acrylate/methacrylates UV cured coatings. Prog Org Coat 54(1):10–19CrossRefGoogle Scholar
  23. 23.
    Odian G (2004) Principles of polymerization. 4th edn. Wiley, New YorkGoogle Scholar
  24. 24.
    Taylor LT (2009) Supercritical fluid chromatography for the 21st century. J Supercrit Fluids 47(3):566–573CrossRefGoogle Scholar
  25. 25.
    Maftouh M, Granier-Loyaux C, Chavana E, Marini J, Pradines A, Heyden YV, Picard C (2005) Screening approach for chiral separation of pharmaceuticals: part III. Supercritical fluid chromatography for analysis and purification in drug discovery. J Chromatogr A 1088(1–2):67–81CrossRefGoogle Scholar
  26. 26.
    Miller JA, Lin SB, Hwang KKS, Wu KS, Gibson PE, Cooper SL (1985) Properties of polyether-polyurethane block copolymers: effects of hard segment length distribution. Macromolecules 18(1):32–44CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  • Justin M. Sirrine
    • 1
  • Mehdi Ashraf-Khorassani
    • 1
  • Nicholas G. Moon
    • 1
  • Ryan J. Mondschein
    • 1
  • Timothy E. Long
    • 1
  1. 1.Department of ChemistryMacromolecules Innovation Institute, Virginia TechBlacksburgUSA

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