HET acid based oligoesters – TGA/FTIR studies

Authors

Thangamani Rajkumar, Kamaraj College of Engineering and TechnologyFollow
Chinnaswamy Thangavel Vijayakumar, Kamaraj College of Engineering and Technology
Palanichamy Sivasamy, Ayya Nadar Janaki Ammal College
Charles A. Wilkie, Marquette UniversityFollow

Document Type

Article

Publication Date

2008

Source Publication

European Polymer Journal

Abstract

One of the important reactive halogenated dicarboxylic acids used in the synthesis of flame retardant unsaturated polyester resins is 1,4,5,6,7,7-hexachlorobicyclo [2.2.1] hept-5-ene-2,3-dicarboxylic acid (HET acid). In the present investigation four different oligoesters are synthesized using HET acid as the diacid component and 1,2-ethane diol, 1,2-propane diol, 1,3-propane diol and 1,4-butane diol as the aliphatic diols. Melt condensation technique in vacuum is used for the synthesis of the oligoesters. The number average molecular weights of the oligoesters are determined using end group analysis. The degree of polymerization is estimated to be 3–5. The structural characterization is done using FTIR and NMR (¹H and ¹³C) techniques. In the present investigation, TGA-FTIR studies for the different oligoesters are carried out in nitrogen atmosphere. The materials are heated from ambient to 600 °C at a heating rate of 20 °C/min. The main volatile products identified are CO, HCl, H₂O, CO₂, hexachlorocyclopentadiene and HET acid/anhydride. The evolution profile of these materials with respect to the structure of the oligoesters is discussed in detail and presented. The importance of β-hydrogens in the diol component and the plausible mechanism for the flame retardant behavior of these oligoesters are presented.

Comments

Accepted version. European Polymer Journal, Volume 44, Issue 6, pp 1865-1873 (June, 2008). DOI: © 2008 Elsevier Ltd. Used with permission.

Recommended Citation

Rajkumar, Thangamani; Vijayakumar, Chinnaswamy Thangavel; Sivasamy, Palanichamy; and Wilkie, Charles A., "HET acid based oligoesters – TGA/FTIR studies" (2008). Chemistry Faculty Research and Publications. 98.
https://epublications.marquette.edu/chem_fac/98