Chemical Modification of Molten Polypropylene by Thermolysis of Peroxidic Compounds

Abstract

The modification recently developed for polyethylene, based on the thermolysis of peroxyketals and peroxy esters in the molten polymer, was applied to atactic and isotactic polypropylene. The grafting of an ester function onto the backbone of these polyolefins was much less efficient in this case than for the former. The thermal decomposition of such peroxides in polyethylene and isotactic and atactic polypropylenes was analyzed by DSC. These studies showed that the physical state of the polyolefin cannot account for the difference encountered in the functionalization yields. The analysis of the reaction products, generated in the thermolysis of a cyclic peroxy ketal, was realized on the extracts by GC and on the bulk by 1H NMR and DOSY spectroscopies. This led one to conclude that the difference in efficiencies in the chemical modification of the various polyolefins is related to the chemical reactivity of the hydrogens toward 1,1-dimethylethyloxy radicals. Surprisingly, it was found that hydrogen abstraction hardly occurs with polypropylene (either isotactic or atactic) despite the presence of thermodynamically more labile tertiary hydrogen atoms than the ones present in polyethylene. This was attributed to the steric hindrance of the methyl present on the backbone of this polyolefin.

Melt functionalization of linear low‐density poly(ethylene) with succinimide and N‐hydroxy succinimide by thermolysis method

“…FTIR spectrometer is a useful tool for various science and engineering fields, because of its high sensitivity or detectivity toward traces amount of substance, low noise to signal ratio and this method is an easy and inexpensive one. FTIR spectroscopy is used for both qualitative [14][15][16][17][18][19] and quantitative [20][21][22][23][24][25][26][27][28][29][30] purposes. By thorough literature survey, we could not find any report based on FTIR based kinetics of SI and NHS functionalized LLDPE.…”

Catalytic activity of V 2 O 5 on aniline polymerization and the study of structural properties of poly(aniline)/V 2 O 5 nano composite

“…The analytical method particularly, FTIR spectroscopy is a useful tool in various science and engineering fields, because of it being eco-friendly, its high sensitivity or detection ability towards traces amount of sample, low noise to signal ratio and since the method is easy and inexpensive one. FTIR spectroscopy is used for qualitative [16][17][18][19][20][21] and quantitative [22][23][24][25][26][27][28][29][30][31][32] applications. Even after thorough literature survey, we could not find any report based on the FTIR based kinetics of effect of nano-sized material on the structure of PANI.…”

Melt functionalization of LDPE with thio ester, amino ester, and hydroxy ester by thermolysis method—An FTIR study

“…Analytical method, particularly FTIR spectroscopy method, does not require any solvent and a useful tool for various science and engineering fields, because of its low noise to signal ratio, easy operation procedure, environmentally green, and inexpensive one. FTIR spectroscopy is used for both qualitative23–25 and quantitative26–38 analysis. By thorough literature survey, we could not find any report based on the FTIR‐RI kinetic method for the estimation of ester grafting of the above said systems.…”