Methacrylic acid

About: Methacrylic acid is a research topic. Over the lifetime, 13058 publications have been published within this topic receiving 173201 citations. The topic is also known as: α-Methacrylic acid & 2-Methylacrylic acid.

Determination of the Rate Constant for Chain Insertion into Poly(methyl methacrylate)-block-poly(methacrylic acid) Micelles by a Fluorescence Method

Abstract: Poly(methyl methacrylate)-block-poly(methacrylic acid) (PMMA-b-PMAA) with and without pyrene labels attached to the end of the PMAA block have been synthesized and characterized. These polymers formed micelles with PMAA as the core in ethyl acetate/methanol mixtures when the ethyl acetate volume fraction was higher than 80%. After mixing a micelle solution of PMMA-b-PMAA without pyrene labels, i.e., polymer I, with a unimer solution of the sample with pyrene, i.e., polymer II, the fluorescence intensity IPy(t) of pyrene increased with time. This was caused by the insertion of the pyrene group of polymer II chains into the rigid core of polymer I micelles. The pyrene fluorescence quantum yield is higher in a more rigid environment due to the reduced quenching of pyrene fluorescence by oxygen and the possible suppression of certain nonradiative deactivation pathways. A kinetic model has been proposed for describing the chain insertion process. Fitting the experimental fluorescence intensity data using the d...

Coassembly of Poly(ethylene oxide)-block-poly(methacrylic acid) and N-Dodecylpyridinium Chloride in Aqueous Solutions Leading to Ordered Micellar Assemblies within Copolymer Aggregates

Abstract: Formation of polyelectrolyte–surfactant (PE–S) complexes of poly(ethylene oxide)-block-poly(methacrylic acid) (PEO705–PMAA476) and N-dodecylpyridinium chloride (DPCl) in aqueous solution was studied by static and dynamic light scattering (SLS, DLS), small-angle neutron scattering (SANS), small-angle X-ray scattering (SAXS), and cryogenic transmission electron microscopy (cryo-TEM). While it was found previously [Macromolecules1997, 30, 3519] by microcalorimetric titration that in a similar system (PEO176–PMAA186) crystallization of aliphatic tails of N-dodecylpyridinium bromide did not occur, in our system it was evidenced by SAXS that upon addition of DPCl to fully ionized PEO705–PMAA476 the ordered arrangement of the surfactant occurs in a certain range of PEO705–PMAA476 concentrations and surfactant-to-polyelectrolyte charge molar ratio (Z). Our data suggest a four-step process in the behavior of the PEO705–PMAA476/DPCl system: (i) coexistence of loose aggregates of electrostatically bound surfactants ...

Graft copolymers having hydrophobic backbone and hydrophilic branches. X. Preparation and properties of water‐dispersible polyanionic microspheres having poly(methacrylic acid) branches on their surfaces

Abstract: The free radical copolymerization of poly(t-butyl methacrylate) (PBMA) macromonomer with styrene in ethanol give monodispersed microspheres with 0.8-1.6 μm diameter. The resulting microspheres were treated with HCl solution to convert into anionic microspheres having poly(methacrylic acid) chains. ESCA analysis of the microsphere surface suggested that PBMA chains were favorably located on the surface of the microspheres. The particle size of the microspheres decreased with increasing molecular weight and concentration of the macromonomer. Water dispersibilities of the microspheres were evaluated by measuring the relative turbidity of the suspension of microspheres as a function of pH. The results show that they were strongly dependent on pH. © 1995 John Wiley & Sons, Inc.