Ionic nanocomposite networks in poly(styrene‐co‐methacrylic acid) copolymers with calcium carbonate

Abstract

To create reversible supramolecular ionic networks, ionic cross-links were formed from acid pendant functions in poly(styrene-co-methacrylic acid) copolymers by the addition of calcium carbonate. The random dispersion of acid functions in the polystyrene chain is ensured by NMR analysis. The partial reaction of the calcium carbonate with the carboxylic acids is highlighted by a limewater test. The influence of methacrylic acid and calcium-carbonate contents on the formation of an ionic network has been studied through solubility tests. Two main effects were obtained: the exfoliation of the unreacted calcium carbonate characterized by TEM is due to ionic interactions at the surface of nanometric particles that form the first level of organization of the calcium carbonate. Another part of the calcium carbonate reacts with carboxylic acid and is detached from particles to form clusters as shown by x-ray analysis. Finally, by analyzing the dynamic rheological spectrum, the conclusion that the strength of the ionic bonds arises with the calcium content is made. The interest of such an approach with a wide range of observed phenomena in the material is a one-batch process to make thermoreversible nanocomposite networks.

Effects of antimicrobial agents on the thermal and mechanical properties of acrylate hydrogel matrices

“…These observations are consistent with the DMTA and densities results; they confirm the aggregation effects on the T g and the storage modulus …”

Rheological study of quaternary ammonium‐containing star‐shaped polylactic acid

“…These ensembles are called aggregates, clusters, or multiplets according to their shape and size. [20][21][22][23][24][25][26] This behavior has been demonstrated by using many techniques such as scanning electron microscopy, 27 magnetization measurements and electron spin resonance, 27,28 dielectric loss measurements, 29,30 Raman spectroscopy, 31 small angle X-ray and neutron scattering, [32][33][34][35] dynamic mechanical analyses, and stress relaxation studies, [36][37][38] rheological studies in the melt phase are also much used to this purpose. [39][40][41][42] The formation of ionic associations in ion-containing polymer leads to an increase in the melt viscosity and changes the flow behavior of the polymer, 33,43 the magnitude of this change depends on many parameters-the nature of the polymer chains bearing the ionsthe ions content (functionality) and their location in the polymer chain backbone-the kind of ions and the counter ions 44 -it depends also on the macromolecular design of the polymer, such as the branched ion-containing polymers are more able to initiate this phenomenon than the linear ones.…”

“…These bonds take place between the ions and cause the formation of packs of polymeric molecules in a form of discrete regions within the polymer. These ensembles are called aggregates, clusters, or multiplets according to their shape and size . This behavior has been demonstrated by using many techniques such as scanning electron microscopy, magnetization measurements and electron spin resonance, dielectric loss measurements, Raman spectroscopy, small angle X‐ray and neutron scattering, dynamic mechanical analyses, and stress relaxation studies, rheological studies in the melt phase are also much used to this purpose …”

Poly(vinyl alcohol)/CaCO3‐diacid nanocomposite: Investigation of physical and wetting properties and application in heavy metal adsorption

“…In the context of the preparation of polymer/CaCO 3 composite, various polymers have been thanked to their excellent properties like, bio‐safe processibility and low cost . Based on previous studies, poly(vinyl alcohol) (PVA) is a potential hydrophilic polymer with nontoxicity, high light transmission, durability, lower cost, good biocompatibility, biodegradable properties which has been used as a polymer matrix .…”