OSA's Digital Library

Applied Spectroscopy

Applied Spectroscopy


  • Vol. 52, Iss. 4 — Apr. 1, 1998
  • pp: 488–495

Crystallinity Determination of Polylactide by FT-Raman Spectrometry

Deru Qin and Robert T. Kean

Applied Spectroscopy, Vol. 52, Issue 4, pp. 488-495 (1998)

View Full Text Article

Acrobat PDF (253 KB)

Browse Journals / Lookup Meetings

Browse by Journal and Year


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools

  • Export Citation/Save Click for help


The complete Raman spectra of isotropically crystalline and amorphous polylactide (PLA) have been successfully obtained with the use of a Fourier transform instrument equipped with a near-IR laser source. The Raman spectra of PLA were recorded at a resolution of 4 cm -1 from a backscattering sampling geometry. The changes in band intensity and shape of Raman spectra in the crystalline PLA samples facilitated the quantification of the crystallinity, which was primarily determined by the change in enthalpy via differential scanning calorimetry (DSC). A comparison of quantitative analysis of crystallinity by a multivariate technique, partial leastsquares (PLS), and a univariate method at the carbonyl stretching band is described. Quantitative analysis of PLA crystallinity was performed after the data preprocessing with the standard normal variate (SNV) method in the combined spectral regions 3100-2800 cm -1 and 2000-200 cm -1 that were determined by the analysis of the correlation spectrum. The use of the calibration model containing mostly 1% D-PLA samples to separately analyze the samples with 1% and 5% D-PLA is discussed. Superior results obtained from the multivariate over the univariate method make PLS the preferred method of choice in quantification of crystallinity. The standard error of prediction (SEP) for the analysis of 1% D-PLA samples with the use of the calibration model described is 0.85 ( J/g), and the SEP for 5% D-PLA samples is 1.35 ( J/g) with the outliers excluded. The discrepancy in analyzing these two types of PLA samples with the use of the same calibration model is also discussed.

Deru Qin and Robert T. Kean, "Crystallinity Determination of Polylactide by FT-Raman Spectrometry," Appl. Spectrosc. 52, 488-495 (1998)

Sort:  Journal  |  Reset


References are not available for this paper.

Cited By

OSA is able to provide readers links to articles that cite this paper by participating in CrossRef's Cited-By Linking service. CrossRef includes content from more than 3000 publishers and societies. In addition to listing OSA journal articles that cite this paper, citing articles from other participating publishers will also be listed.

« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited