Please use this identifier to cite or link to this item: http://scholarbank.nus.edu.sg/handle/10635/67604
Title: X-ray photoelectron spectroscopic characterization of protonation of polyaniline films by polymeric acids
Authors: Kang, E.T. 
Neoh, K.G. 
Tan, K.L. 
Keywords: polyaniline films
protonation by polymeric acids
X-ray photoelectron spectra
Issue Date: Jul-1994
Source: Kang, E.T.,Neoh, K.G.,Tan, K.L. (1994-07). X-ray photoelectron spectroscopic characterization of protonation of polyaniline films by polymeric acids. Polymer 35 (15) : 3193-3199. ScholarBank@NUS Repository.
Abstract: The protonation behaviour of emeraldine (EM) films by two polymeric acids, poly(acrylic acid) (PAAc) and poly(styrenesulfonic acid) (PSSAc), was studied by X-ray photoelectron spectroscopy (X.p.s.). The EM-PAAc films were prepared by direct protonation of EM films in aqueous PAAc medium, by blending of EM and PAAc in N-methylpyrrolidinone (NMP) and by near-ultra-violet light-induced surface graft copolymerization of EM film with acrylic acid. EM-PAAc salts were also prepared by direct polymerization of aniline in PAAc solutions. Relatively weak charge-transfer interactions or low protonation levels were observed in all cases, even in the presence of a large excess of PAAc units. However, in the presence of a strong acid such as PSSAc, almost all the amine nitrogens in the surface region of the EM film, in addition to the imine nitrogens, were susceptible to protonation. Furthermore, deprotonation of the PSSAc protonated EM film, but not the PAAc protonated EM film, was accompanied by a substantial increase in the intrinsic oxidation state of the EM film, leading to the 75% intrinsically oxidized nigraniline state. Lower extent of surface hydrolysis reaction was also observed during protonation by the polymeric acid than by mineral acids. © 1994.
Source Title: Polymer
URI: http://scholarbank.nus.edu.sg/handle/10635/67604
ISSN: 00323861
Appears in Collections:Staff Publications

Show full item record
Files in This Item:
There are no files associated with this item.

Page view(s)

58
checked on Dec 8, 2017

Google ScholarTM

Check


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.