Spectrum bx ft ir system

The experiments were performed on a Perkin-Elmer Spectrum BX FT-IR system. The spectra of the samples were recorded at room temperature in the wavenumber range of 400–4000 cm⁻¹ using an ATR cell.

To verify the treatment of the wool, attenuated total reflectance Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analyses (TGA) were performed in unmodified wool (UW) and in all the wool fibers modified with coupling agents A, B, C and D (labeled as WA, WB, WC and WD, respectively). FTIR was recorded using a Perkin Elmer Spectrum BX FTIR system (Beaconsfield, United Kingdom) within the range of 4000–650 cm⁻¹. The resolution used was 16 cm⁻¹ and 20 scans were fulfilled. TGA was conducted in Linseis TGA PT1000 (Selb, Germany) in a dynamic mode with a heating rate of 10 °C/min, from 30 to 700 °C, in a nitrogen atmosphere (flow 20 cm³/min). The onset degradation temperatures (T₅) were determined at 5% of mass loss, while temperatures of the maximum decomposition rate (T_max) were calculated in the temperature of the peak from the first derivative of the TGA curves (DTG). TGA analyses were performed by triplicate and the average and standard deviation of the values are reported. Significance in the data differences was statistically analyzed with OriginPro 8 software (OriginLab, Northampton, MA, USA). The significant differences among the wool fiber samples were recorded at 95% confidence level according to Tukey’s test using the one-way analysis of variance (ANOVA).

Optical rotations were determined with a Perkin Elmer 341 polarimeter. IR spectra were recorded on an FT-IR spectrophotometer, Perkin Elmer, Spectrum BX FTIR System. ¹H and ¹³C NMR measurements were obtained on Agilent-400MHz, Agilent-500MHz, and Agilent-600MHz NMR spectrometers with SiMe₄ as the internal reference. High-resolution mass spectrometry (HRMS) was performed using a Q-TOF mass spectrometer in the positive-ion ESI mode. HPLC was performed with a Hitachi/Merck L-6270 apparatus equipped with a UV-VIS detector (L 6200) and a differential refractometer detector (RI-71). TLC was performed on Merck Kiesegel 60 F254, 0.2 mm thick. Silica gel (Merck) was used for column chromatography. Purification by means of HPLC was done with a Silica gel column (Hibar 60, 7 m, 1 cm wide, 25 cm long). Chemicals were provided by Fluka (Buchs, Switzerland) and Aldrich (Sigma-Aldrich, Darmstadt, Germany). All solvents used were freshly distilled. Baker’s yeast was obtained from a local shop. The following enzymes were used in this work: Candida rugosa Lipase (Sigma, Darmstadt, Germany, Type VII, 950 U/mg) and Porcine Pancreas Lipase (Sigma, Darmstadt, Germany, Type II) (Sigma-Aldrich, Darmstadt, Germany). Enantiomeric excesses were determined by means of HPLC analyses on a chiral column (Chiralcel OD, Daicel, Japan, 254 nm) with n-hexane/i-PrOH 95:5 as eluent, flow rate 0.8 mL/min.