400 mhz nmr

Solvents were dried and deoxygenated by refluxing over the appropriate reagents before use. Elemental analyses were obtained from a PE 2400 series II CHNS/O analyzer (PerkinElmer, Boston, MA, USA) or an Elementar Vario EL cube analyzer (Elementar Americas Inc., Ronkonkoma, NJ, USA). ¹H-NMR and TOF-MS (ESI-MS) were recorded on a Bruker 400 MHz NMR and a Bruker MicrOTOF II (Bruker, Billerica, MA, USA), respectively. Powder X-ray diffraction patterns were obtained from a Bruker D2 PHASER diffractometer (Bruker, Billerica, MA, USA) with CuK_α (λ_α = 1.54 Å) radiation. IR spectra (KBr disk) were recorded on a Jasco FT/IR-460 plus spectrometer (JASCO, 28600 Mary’s Court City, MD, USA). The UV-Vis absorption spectra and emission spectra were obtained in the solid state at room temperature by using an SP-1901 UV-Vis spectrophotometer (Shimadzu, Kyoto, Japan) and a Hitachi F-4500 spectrometer (Hitachi, Tokyo, Japan), respectively. Thermal gravimetric analysis (TGA) was carried out on a SII EXSTAR6000 TG/DTA 6200 (Seiko Instruments Inc., Tokyo, Japan) under N₂ atmosphere at a heating rate of 10 °C min⁻¹ in the temperature range of 30 to 1000 °C.

All chemical reagents and solvents were purchased from commercial sources (Sigma-Aldrich, St. Louis, MO, USA; BroadPharm, San Diego, CA, USA; Fisher Scientific, Hampton, NH, USA) and used as received unless otherwise stated. For aqueous buffer solution preparation, Milli-Q water was obtained from a Millipore Gradient Milli-Q water system (Burlington, MA, USA). Nuclear magnetic resonance (NMR) spectra were recorded on a Bruker 400 MHz NMR (Billerica, MA, USA). Liquid Chromatography-Mass Spectrometry (LC-MS) of compounds were performed by an Agilent 6540 Accurate-Mass Quadrupole Time-of-Flight LC/MS system equipped with 1290 UPLC (Santa Clara, CA, USA). HPLC purifications were performed in an Agilent 1260 Infinity Preparative HPLC system equipped with 1260 photodiode array detector (PDA) and an Agilent Prep-C18 column (150 × 21.2 mm, 5 μm) (Santa Clara, CA, USA). The radiolabeled compounds were characterized by a Waters 600 HPLC system equipped with a Waters 2996 PDA (Milford, MA, USA) and an in-line Shell Jr. 2000 radio detector (Spotsylvania, VA, USA).

¹H nuclear magnetic resonance (¹HNMR) measurement: Ten milligrams of A-PEO-PCL, A-PEO-P(CL-SP), TAT-PEO-PCL, and DCL-PEO-PCL were separately and fully dissolved with 0.5 mL deuterium chloride in nuclear magnetic tubes. A Bruker 400 MHz NMR (Switzerland) instrument was applied to measure the ¹HNMR spectra.
GPC measurement: Five milligrams each of A-PEO-PCL, A-PEO-P(CL-SP), TAT-PEO-PCL, and DCL-PEO-PCL was dissolved in chromatographic grade THF and filtered after ultrasonic degassing. Polystyrene was selected as the standard sample. After injection into a gel chromatography column (Waters, USA), the elution time was measured, and the molecular weight was calculated.
Fourier transform infrared spectroscopy (FT-IR) measurement: Dry potassium bromide and a small amount of dried sample powder were ground into a powder. The two compounds were pressed into tablets until evenly mixed. Infrared spectroscopy was performed by placing the tablet in an infrared spectrometer (Bruker, Germany).

The NMR spectrum of EALYS 1:4 was recorded using a Bruker 400 MHz NMR on 10 mg of EALYS 1:4 dissolved in 1 mL of deuterium oxide (D₂O). ¹H-NMR (400 MHz, D₂O): δ 7.13 (1H, s), 3.58 (2H, t, J = 6 Hz), 2.90 (4H, t, J = 8 Hz), 1.75 (4H, m), 1.60 (4H, dd, J = 8, 6 Hz), 1.35 (4H, m).

The ¹⁹F NMR experiments were conducted at 25 °C on a Bruker 400 MHz NMR equipped with HFXY 4 mm MAS probe. The ¹⁹F static and magic angle spinning (MAS) experiments at 10 kHz spinning speed were performed at 376.5 MHz, using a ca. 78 kHz single pulse excitation with ca. 55 kHz SPINAL64 ¹H decoupling, a 5 s recycle delay, a spectral width of 250 kHz, 8 k complex points acquisition zero-filled to 16 k points and line broadening ranging from 50 Hz to 100 Hz. Spectra were externally referenced using trifluoroacetic acid (−76.5 ppm) prior to each MAS experiment. Typically 20 k scans and 16 k scans were acquired for the static and MAS ¹⁹F NMR spectra.

FTIR spectroscopy was done to identify and quantify functional groups for the aging characterization of the TPC and PPC-modified asphalt binders. A PerkinElmer UATR Two FTIR spectrometer working in attenuated total reflection (ATR) mode was used with an accumulation of 64 scans in the 400–4000 cm^–1 range. Binder samples were dissolved in tetrahydrofuran at a concentration of 10% w/v. ¹H NMR analysis was conducted on a Bruker 400 MHz NMR. The binder samples (about 20 mg) were dissolved in deuterated chloroform (CDCl₃) and placed in 5 mm NMR tubes. FTIR and NMR were performed twice for each binder, and average results were reported.