Study of Vinyl Acetate Partitioning in Emulsion Copolymerization of Vinyl Chloride-Vinyl Acetate by FTIR and HNMR Spectroscopy |
| |
Authors: | Hamid Salehi-Mobarakeh Mostafa Hassannia Roudboneh |
| |
Affiliation: | (1) Department of Polymer Science, Faculty of Science, Iran Polymer and Petrochemical Institute, P.O. Box 14965-115, Tehran, Iran |
| |
Abstract: | Emulsion copolymerization of vinyl chloride with vinyl acetate comonomer was performed. Potassium persulfate, a mixture of
stearyl alcohol and sodium lauryl sulfate, was used and reactions were performed at 55 °C in a pressurized reactor. By sampling
during the reaction in different intervals copolymer composition was investigated using FTIR and NMR spectroscopy. The results
showed that the partitioning of vinyl acetate in the copolymerization in general follows the Mayo-Lewis copolymerization equation
with some discrepancy. This was attributed to the gaseous nature of vinyl chloride monomer and the differences between polymerization
in heterogeneous and homogeneous systems. Both FTIR and NMR spectroscopy showed two peaks in vinyl acetate content of copolymer
beyond 65% conversion which was attributed to the elimination of vinyl chloride droplets in the media and replacing them with
vinyl acetate monomer. The first increase is related to the consumption of vinyl chloride droplets and the second is related
to the consumption of gaseous vinyl chloride; in both instances vinyl acetate governs the polymerization. |
| |
Keywords: | emulsion copolymerization pressure vinyl chloride vinyl acetate conversion HNMR FTIR Mayo-Lewis |
本文献已被 SpringerLink 等数据库收录! |