Analysis of plasma polymerization of allylamine by FTIR

Abstract

SynopsisThe plasma polymerization of allylamine in an inductively coupled rf plasma reactor is analyzed by Fourier transform infrared spectroscopy. Comparison of the infrared spectra of the as-received monomer and the plasma polymerized f i l m reveals a conversion of the primary amine in the monomer (-CH,-NH,) to an imine (-CH=NH) and a nitrile (C-N). Plasma polymerization of ethylenediamine yields the same results, suggesting that this polymerization scheme may be typical of primary amines. Increasing the plasma power seems to increase the proportion of nitrile groups in relation to the imine groups. The infrared spectra of the vapor phase polymerized monomer was similar to that of the substrate-grafted allylamine f i l m implying a similar structure. Aging of this vapor phase polymer at 120°C for 1 h in vacuum and at 295°C for 15 min in an oxygen free environment reveals nitrile group reaction similar to that observed in polyacrylonitrile. Thermogravimetric analyses of the vapor phase polymers in a nitrogen atmosphere at 2OoC/min demonstrated the thermal stability, with the polymer produced at a plasma power level of 50 W retaining 20% of its weight at 1OOO"C. This was better than the stability shown by the polymer produced at 150 W and is attributed to the ease of nitrile group polymerization in the former. *The assignments of the infrared absorptions are based on references 15 and 16.

Production and preliminary characterization of DC plasma polymerized allylamine film (PPAA) by NRA, ERD and XPS

“…In particular, PPAA is much less hydrogenated than the monomer. This was already observed by Krishnamurthy et al [11].…”

A Comparative X‐Ray and Neutron Reflectometry Study of Plasma Polymer Films Containing Reactive Amines

“…This may also be due, in part, to some retention of the original double bond in the AA molecule after deposition of the AApp thin film and generation of unsaturated species during plasma deposition. Previous researchers have shown that the use of unsaturated monomers such as allylamine favors the formation of reactive unsaturated species such as imines and nitriles 46. Analysis of the high resolution carbon (C1s) spectra of the AApp (not shown) reveals a film that is rich in hydrocarbon and carbon‐nitrogen and carbon‐oxygen moieties such as amine and amide containing species.…”

Swelling signals of polymer films measured by a combination of micromechanical cantilever sensor and surface plasmon resonance spectroscopy

“…It was found that the structure and chemical nature of the plasma-polymerized allylamine (PPAA) films depends on the plasma conditions [29][30][31][32]; different film properties can be generated from the same monomer. In particular, the crosslink density of the films is directly dependent on the plasma power used during the deposition process.…”