Surface and interfacial FTIR spectroscopic studies of latexes. XIII. Surfactant exudation in silicone-modified latex films

Abstract

Exudation of sodium dioctylsulfosuccinate (SDOSS) surfactant molecules to the film–substrate (F–S) and film–air (F–A) interfaces in styrene/n‐butyl acrylate (Sty/n‐BA) latex films in the presence of trimethoxysilyl propylmethacrylate (MSMA) molecules was examined by polarized attenuated total reflection Fourier transform infrared (ATR FTIR) spectroscopy. It appears that SDOSS molecules are present at the F–A interface but are not detected at the F–S interface due to their displacement by MSMA. When the second layer of latex is deposited on the previously coalesced latex film with the same composition, SDOSS molecules are detected at the F–A of the top overlayer and the interfacial regions between both films. While the top film contains SDOSS surfactant molecules in their free or COOH hydrogen‐bonded forms, the interfacial regions between the films exhibit arrays of SDOSS molecules preferentially parallel to the film surface. © 1996 John Wiley & Sons, Inc.

Phase Separation and Surfactant Stratification in Styrene/n-Butyl Acrylate Copolymer and Latex Blend Films. 17. A Spectroscopic Study

“…Similarly, the 1056 and 1046 cm -1 bands are attributed to the S-O symmetric stretching modes resulting from SO 3 -Na + ‚‚‚COOH and SO 3 -Na + ‚‚‚H 2 O interactions. [1][2][3][4][5][6][7][8][9][10][11][12][13] Trace B of Figure 1 illustrates an ATR spectrum recorded from the F-S interface, and it appears that the bands due to pure SDOSS and/or SDOSS associations are not detected. Thus, comparison of the spectra recorded from both interfaces indicate that, for Sty/n-BA copolymer latex, SDOSS exudes to the F-A interface.…”

“…Figure 1, traces C and D, shows ATR FT-IR spectra recorded from the F-A and F-S interfaces of p-Sty/p-nBA latex blend, respectively. As seen, only traces of the SDOSS bands at 1056 and 1046 cm -1 due to S-O symmetric stretching modes of SO 3 -Na + ‚‚‚COOH and SO 3 -Na + ‚‚‚H 2 O associations [2][3][4][5][6][7][8][9][10][11] are detected at the F-A interface (trace C), but as compared to the F-S interface (trace D), they are stronger, indicating that only small quantities of SDOSS exude to the F-A interface. Overall, SDOSS bands at 1288, 1259, 1232, 1208, 1181, 1056, and 1046 cm -1 are significantly stronger in trace A than those in trace C, indicating that there is a greater degree of SDOSS accumulation near the F-A interface for copolymer latex than for its counterpart latex blend.…”

“…While elimination of the VOC is an important task, the consequences resulting from a higher water content generate a spectrum of problems among which wettability of low surface tension substrates as well as stratification of polymer dispersions during their film formation is one of the primary concerns. A series of previous studies on latex films indicated that the mobility of low molecular weight species, in particular surfactant molecules, may be affected by latex glass transition temperature (T g ), and subsequently by the free volume of a polymer matrix, 1,2 surface tension at the film-air (F-A) and film-substrate (F-S) interfaces, [3][4][5][6][7][8] compatibility, [9][10][11][12][13][14][15][16] and coalescence times. [16][17][18] However, there are other factors that not only influence distribution of individual components, but may also significantly affect various stages of latex film formation.…”

Mobility of SDOSS Powered by Ionic Interactions in Sty/n-BA/MAA Core−Shell Latex Films. 21. A Spectroscopic Study

“…Previous studies on latex films indicated that the mobility of SDOSS molecules was affected by the compatibility of SDOSS with a polymer matrix, [5][6][7][8][9][10][11][12] temperature (T c ), 13 and glass transition temperature (T g ). 14 However, such factors as latex particle surface hydrophilicity, that not only influence distribution of individual components, but may also significantly affect film formation and the formation of ordered surfactant structures, are important.…”

Surface and interfacial FTIR spectroscopic studies of latexes. XII. Particle size effect and surfactant behavior in electrodeposited Sty/n-BA latex films

“…As we have already established and cross-referenced with the literature data,g a comparison of the reactivity ratios for styrene and n -BA favors styrene homopolymerization, and the formation of the polystyrene core and poly( n-BA) shell occurs for the larger particle sizes. 13 In contrast, for smaller particle sizes, more homogeneous distribution for S t y / n -BA particle cross-section is anticipated. As a result, the 1056 cm-' band is detected for larger particle-size latexes, but it is not detectable for smaller particles since there are minimal or no COOH ---SO; Na' interactions.…”