Accession Number:

ADA281187

Title:

UV and Fluorescence Studies for Vinyl Polymerization

Descriptive Note:

Technical rept. no. 41, Jun 1993-May 1994

Corporate Author:

CONNECTICUT UNIV STORRS INST OF MATERIALS SCIENCE

Personal Author(s):

Report Date:

1994-06-01

Pagination or Media Count:

5.0

Abstract:

Polymerizations of styrene and methyl methacrylate MMA in bulk as well as in solutions were followed by UV-Visible and fluorescence spectroscopies as potential on-fine monitoring techniques. For the solution polymerization of styrene, the monomer conversion obtained by UV and fluorescence measurements could be correlated with IR results at three different temperatures 65, 70, and 75 deg C. From the initial slope at each temperature, the activation energy of about 6Kcalmol was determined. For MMA solution polymerization, UV of MMA and fluorescence of styrene laced as an extrinsic sensor were monitored. The monomer conversion of this reaction could be obtained by measuring fluorescence intensity of styrene through the correlation curve. Bulk polymerization of styrene was in-situ monitored by using fluorescence fiber-optic cable. The fluorescence intensity of styrene in bulk became significant only after 80 monomer conversion because of self-quenching effect. Bulk polymerization of MMA was followed by UV reflection technique. The initial peak appeared at 225 nm was gradually shifted to the shorter wavelength with polymerization, which is not observable in UV transmission absorption spectra. Also, the percent reflectance increased with reaction. Based on these results, this technique showed a promising future as an on-line monitoring tool. UV and fluorescence spectral changes, Polymerization of vinyl monomers, MMA, Styrene, Fiber optic monitoring, In-situ polymerization.

Subject Categories:

  • Inorganic Chemistry
  • Polymer Chemistry
  • Atomic and Molecular Physics and Spectroscopy
  • Optics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE