Styrene Ionomers Research Articles

Effects of Styrene Ionomers on the Dispersion of Asphaltenes in Crude Heavy Oil

The purpose of this work was to investigate the effects of polystyrene-based acidic copolymers and ionomers on the dispersion of asphaltenes in heavy oil. In the first part of the work, we studied ...

Mechanical Properties of Poly(methyl methacrylate-co-3-sulfopropyl methacrylate) Ionomers Acting as a Filled System

The dynamic mechanical properties of newly-made poly(methyl methacrylate-co-3-sulfopropyl sodium methacrylate) (M-SPMA) ionomers were measured and compared with those of methyl methacrylate ionomers having sodium methacrylate units (M-MA) and styrene ionomers having SPMA or MA units (S-SPMA or SMA). It was observed that the position of the matrix loss tangent peak of M-SPMA ionomers was not changed by the ion content, but the size of the peak was decreased. At high ion contents, however, the ionomers showed a cluster loss tangent peak and a very weak SAXS peak. These results were quite different from those obtained from the styrene ionomers. Thus, it was concluded that this dissimilarity was due to the differences in the polarity and persistence length of PS and PMMA. When the mechanical data of M-SPMA ionomers were compared with those of M-MA ionomers, M-SPMA and M-MA ionomers were found to behave like a filled system and a cross-linked system, respectively. This was due to the fact that M-SPMA ionomers had propyl groups and sodium sulfonate ion pairs, and thus the ionic groups formed fewer and larger ionic aggregates than M-MA ionomers.

Studies of plasma treated styrene-based ionomers

The aim of the work was to study changes in the surface polarity of styrene ionomers containing Li+, Na+, K+ and Cs+ acrylates after air plasma treatment and then to observe the hydrophobic recovery of these samples. Changes in the surface properties were studied by atomic force microscopy (AFM), by measuring contact angles and calculating the surface free energy and its components. The values of surface free energy and its polar component increased considerably after air plasma treatment, which indicated the presence of polar groups on the surfaces. However, these alterations in the sample surfaces were impermanent.

Relations between the neutralization level and clustering of amorphous ionomers

The effect of neutralization level on the dynamic mechanical properties and morphology of partly neutralized poly(ethyl acrylate-co-Na acrylate) EANa ionomers was investigated. The mechanical data of EANa ionomers were compared to those of polystyrene-based ionomers having higher T g but lower ion content than the EANa ionomers. It was found that at ca. 44 % neutralization, compared to ca. 50 % neutralization for styrene ionomers, the ionomers started to show cluster T g and ionic modulus. Thus, it was suggested that the 40–50 % neutralization level might be a starting point, at which the amorphous Na-neutralized ionomers, regardless of the matrix T g and acid content, behaved like bi-phasic materials. The SAXS study suggested that with increasing neutralization level the number of multiplets increased slightly but the number of ion pairs per multiplet increased systematically.

The Influence of UV-Irradiation or Plasma on Ionomer Surfaces

Films of polystyrene and styrene ionomers with various content of sodium acrylate were studied in terms of changes in surface properties after UV-irradiation or plasma action. The alterations were examined by contact angle measurements and FTIR-ATR spectroscopy. Both UV-irradiation (3h and 4h) and the plasma action (30s) induced a growth in the sample hydrophilicity owing to appearance of polar groups on the surfaces. More effective alterations of surface polarity were caused by the plasma action. However, these changes were reversible, contrary to the results caused by UV-irradiation. Photons can penetrate deeper into the sample rendering the changes more durable.

Tangible plasticization/filler effects of sodium salts of dimer acids on the mechanical properties of styrene ionomers

AbstractThe effects of the presence of dimer acid (DA) molecules in Na‐sulfonated polystyrene (PSSNa) and poly(styrene‐co Na‐methacrylate) (PSMANa) ionomers on the ionomer properties were investigated using a dynamic mechanical analysis technique. The DA decreased the matrix and cluster Tgs of PSSNa ionomer without changing the ionic modulus, suggesting that the DA resided both in the matrix and cluster regions of PSSNa ionomer and acted mainly as a plasticizer. On the other hand, the DA decreased the cluster Tg of PSMANa ionomer, without changing the matrix Tg, and also increased the ionic modulus, implying that the DA behaved like plasticizer only for the cluster regions. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Dynamic mechanical properties of polystyrene ionomers containing both carboxylate and sulfonate anionic groups

Polystyrene-based ionomers possessing sodium methacrylate (MA) and sodium styrenesulfonate (SS) units in each polymer chain [poly(styrene-co-methacrylate-co-styrenesulfonate) (PSMA-SS)] were synthesized. The dynamic mechanical properties of PSMA-SS ionomers were studied and compared with those of styrene ionomers containing only MA (PSMA ionomer) or SS (PSS ionomer) units. It was observed that the ionic moduli of PSMA-SS ionomers depended directly on the total ion content and that the ionic modulus was highest for the PSMA ionomer and lowest for the PSMA-SS ionomer. The matrix Tgs of the three ionomer systems were found to be similar to each other; the cluster Tg of PSMA-SS ionomer was higher than that of PSS ionomer at low SS contents but became closer to each other at high SS contents. In addition, the small-angle X-ray scattering study revealed that the multiplet size might be in the following order: PSMA-SS > PSS > PSMA. This implied that at the same ion content, the fractions of cluster regions were smallest for PSMA-SS ionomer in comparison with those of PSS or PSMA ionomers. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012

Poly(Ethylene Oxide)/Styrene Ionomers Blends: Crystallization of Poly (Ethylene Oxide) Component Studied by Wide-Angle X-Ray Diffraction

Wide-angle X-ray diffraction (WAXD) and the scanning electron microscopy (SEM) were used to determine the morphology of crystalline phase of blends of poly(ethylene-oxide) (PEO) and styrene-acrylic acid (S-AA) copolymers neutralized with sodium ions (Na+). In this study, we investigated the effects of blend composition and the content of ionic groups in amorphous ionomers on the degree of crystallinity and the crystallite sizes. It was found that the degree of crystallinity of PEO in the blends decreases both with increasing S-ANa(6.4) content and with increasing ANa content. The sizes of PEO crystallites, measured both in the direction perpendicular and parallel to the polymer axis, are almost independent of ionic groups content in the amorphous component of the blends but they decrease with increasing S-ANa(6.4) content. For the blends containing small amounts of PEO the confined crystallization of this polymer were observed. The final crystalline morphology of these blends, observed by SEM method, is different in comparison to that formed without spatial confinement.

Some properties of styrene‐based ionomers II

AbstractSome properties of styrene‐based ionomers obtained from copolymers styrene (S) and acrylic acid (AA) or methacrylic acid (MA) obtained in emulsion containing alkali metal salts have been investigated. A study has been conducted to examine the influence of the acid content and nature (acrylic or methacrylic) and nature of alkali metal salt on the glass transition temperature, density, melt index, and activation energy of flow of the styrene‐based ionomers.The present studies have indicated that the temperature of glass transition (Tg) of sodium ionomers increases as the sodium content rises, but the increase is lower than in the case of the ionomers based on copolymers obtained in bulk.The density of films rises with the content of alkali metal salt introduced to the polystyrene chain, and it is higher than in the case of the ionomers based on copolymers obtained in bulk containing almost the same content of alkali metal salts. Styrene ionomers containing alkali metal acrylates have higher densities than those containing alkali metal methacrylates. The melt index of the investigated ionomers depends on the amount and type of introduced acid and salt, as well as on the molecular weight of the initial copolymer. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 268–275, 2005

Structure of ionic aggregates of ionomers. II. Effect of humidity and temperature on ethylene and styrene ionomers

AbstractSmall‐angle X‐ray scattering profiles of ethylene and styrene ionomers were studied to clarify the structure of ionic aggregates as a function of humidity or temperature. The intensity and position of ionic cluster peaks were observed for ionomers with a certain degree of neutralization. The intensity of the ionic cluster peak for the ethylene ionomer increased with increasing relative humidity, but it decreased for the styrene ionomer. With increasing humidity, the position of the ionic cluster peak shifted to smaller angles for both ionomers. The size of the ionic aggregates and the closest approach distance between the aggregates were analyzed, and the results varied with humidity for both ionomers. The size did not vary markedly with a change in temperature, whereas the closest approach distance and number of ionic aggregates changed slightly with the melting temperature of the ethylene ionomer and the glass‐transition temperature of the styrene ionomer. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 831–839, 2002

Effects of Two Ionic Groups in an Ionic Repeat Unit on the Properties of Styrene Ionomers

The properties of poly(styrene-co-itaconate) ionomers were studied dynamic mechanically. It was observed that ionic moduli increased as ion content increased and that the increased ionic modulus values were comparable to those of well-clustered polystyrene ionomers. It was also found that only a very weak cluster loss tangent peak was present and that the shoulder-like peak shifted to higher temperatures with increasing ion content. This implies that the itaconate ionomers are weakly clustered materials. Also, the cluster Tg of the itaconate ionomers was found to be much higher than that of the well-clustered poly(styrene-co-methacrylate) ionomers. From these results, it was postulated that in the present ionomer system the ion hopping of the ion pairs in multiplets played an important role in determining the mechanical properties of the ionomers. The SAXS study showed that as ion content increased more ionic groups formed not at the prevalent distances, but very randomly, inferring that the multiplets in...

Structure of Ionic Aggregates of Ionomers. 1. Variation in the Structure of Ionic Aggregates with Different Acid Content and Degree of Neutralization of Ethylene and Styrene Ionomers

Small-angle X-ray scattering profiles of the ethylene and styrene ionomers were studied to clarify the structure of ionic aggregates as a functions of the nature of cations, acid content, and degree of neutralization. The ionic cluster peak was observed for the ionomers with a certain degree of neutralization. The scattering profile of the ionic cluster peak was analyzed by the modified hard-sphere model proposed by Yarusso and Cooper , and the size of ionic aggregates, closest approach distance between the aggregates, and average system volume per ionic aggregate were obtained. The size and distance of the ionic aggregates in the ionomers with monovalent cation, sodium and potassium cations, increased with the ion content (acid content × degree of neutralization), while those with divalent one, zinc and copper cations, and trivalent one, ferric cation, changed only slightly. The number of cations in an ionic aggregate was evaluated in an approximate manner by using the average system volume per ionic aggregate and the density of ionomer or the size of the ionic aggregate and the density of the ionic aggregate estimated by a simple additivity rule for each phase.

Effects of Organic Salts on Dynamic Mechanical Properties of Styrene Ionomers

Effects of Organic Salts on Dynamic Mechanical Properties of Styrene Ionomers

FTIR Investigation of ion‐dipole interaction in styrene ionomer/poly(ethylene oxide) blends

AbstractFourier‐transform infrared (FTIR) spectroscopy was used to examine specific interactions contributing to the partial miscibility in blends of styrene‐sodium methacrylate copolymer (S‐NaMA) and poly(ethylene oxide) (PEO). From the shifts of carboxylatelon and ether group stretching bands, an important specific interaction was found involving ion‐dipole bonding between the ionic group in styrene ionomer and the ether group in PEO. The asymmetric stretching vibration frequency of the carboxylate ion group increases as the fractional amount of PEO in the blend is increased, while the symmetric stretching frequency is decreased. The transition value of the fraction of PEO, above which both vibration frequencies of the carboxylate ion mentioned above remained almost unchanged, increases as the concentration of ionic groups in ionomer is increased. The ether group stretching band shifts to higher frequencies as the PEO content in the ionomer/PEO blend is increased. From the differential scanning calorimetry (DSC) and FTIR studies, we find that the iondipole interaction is the important mechanism that determines the miscibility of S‐NaMA/PEO blends. © 1994 John Wiley & Sons, Inc.

Sizes and stabilities of multiplets and clusters in carboxylated and sulfonated styrene ionomers

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSizes and stabilities of multiplets and clusters in carboxylated and sulfonated styrene ionomersB. Hird and A. EisenbergCite this: Macromolecules 1992, 25, 24, 6466–6474Publication Date (Print):November 1, 1992Publication History Published online1 May 2002Published inissue 1 November 1992https://doi.org/10.1021/ma00050a013RIGHTS & PERMISSIONSArticle Views489Altmetric-Citations123LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (1 MB) Get e-Alerts Get e-Alerts

Alkylated styrene ionomers with variable length spacers. I. Synthesis

AbstractTwo analogous series of ionomer precursors based on 4‐substituted styrene copolymers were prepared with substituents R = ‐(CH2)nCO2Me (n = 1, 5, 10), or R = ‐O(CH2)nCO2Me (n = 1, 4, 10), and degrees of substitution from 10 to 15 mol%. The synthesis of the alkyl series compounds involved either chloromethylation of polystyrene or bromoalkylation via lithiation of a styrene‐4‐bromostyrene copolymer, followed by conversion to the nitriles. Methyl esters were then produced by reaction of the nitriles with methanol/HCl gas. The ether series compounds were obtained directly by reacting a styrene‐4‐hydroxystyrene copolymer with the methyl esters of the corresponding ω‐bromoaliphatic carboxylic acids in a Williamson ether‐type synthesis.

Alkylated styrene ionomers with variable length spacers. II. Physical properties

Etude en fonction de la longueur des espaceurs et de la teneur en groupes ioniques, des proprietes dynamomecaniques d'ionomeres obtenus par hydrolyse basique de precurseurs contenant 10 a 15% en mole de motifs styrene substitues en 4 par des groupes −(CH 2 ) n CO 2 Me (n=1, 5, 10) ou −(CH 2 ) n CO 2 Me (n=1, 4, 10)

Effects of internal plasticization on ion aggregation in a styrene ionomer

Alkylation par le decene-1 d'un copolymere 93/7 styrene-acide methacrylate. Diminution des Tg associees a la matrice et aux agregats ioniques lorsque le degre d'alkylation augmente. Augmentation de l'agregation ionique par rapport a l'ionomere non alkyle lorsque le degre d'alkylation est inferieur a 20%. Au dela, destruction des agregats par les chaines alkyl. Influence non significative des agregats sur les proprietes rheologiques du polymere

Matrix polarity effects on ionic aggregation in a nitrated styrene ionomer

Augmentation de la constante dielectrique d'un copolymere styrene ? methacrylate de sodium par nitration partielle, mais influence nulle sur l'agregation ionique. Etude de la plastification du meme ionomere par le nitrobenzene, montrant que les domaines riches en ion et la matrice sont egalement affectes. Les interactions specifiques semblent plus importantes que la polarite dans le comportement plastifiant des diluants

Ion—dipole interactions in polyether polyurethane—styrene ionomers blends

It is shown that polyurethanes containing polyether segments of MW = 1000 or 2000 are miscible with styrene ionomers. The soft segment interacts with the ionomer via ion—dipole interactions, but some of the hard segments containing ether moieties are also incorporated into the polystyrene.