Topic
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.
Papers published on a yearly basis
Papers
More filters
TL;DR: Observations were related to a description of polyelectrolyte complexation that was strongly dependent on macromolecular dimensions, both in terms of molecular weight and of coil expansion/contraction driven by polyelectrosan/poly(methacrylic acid) complexes.
144 citations
TL;DR: In this paper, the melt rheology of a series of E/MAA ionomers, all based on the same copolymer, with an emphasis on the low-shear-rate Newtonian region, was examined.
Abstract: We examine the melt rheology of a series of ethylene−methacrylic acid (E/MAA) ionomers, all based on the same E/MAA copolymer, with an emphasis on the low-shear-rate Newtonian region. All ionomers show Newtonian behavior at sufficiently low shear rates. The zero-shear viscosity η0 is a strong function of neutralization level and is significantly higher for Zn ionomers than for Na ionomers at the temperatures and neutralization levels examined. The recoverable compliance Je0 is independent of cation type and neutralization level, indicating that the ionic associations bear no stress during steady flow in the terminal region. Therefore, the individual ionic associations have lifetimes much shorter than the terminal relaxation time of the polymer chain. We probe the effect of unneutralized acid groups on η0 by removing these groups through esterification. Unneutralized acid groups substantially lower the viscosity of Na ionomers but have no discernable effect in Zn ionomers. An “acid-cation exchange” mechani...
144 citations
Patent•
14 Jan 1994TL;DR: Air-encapsulating microcapsules as mentioned in this paper are formed by ionotropically gelling synthetic polyelectrolytes such as poly(carboxylatophenoxy)phosphazene, poly(acrylic acid), poly(methacric acid) and methacrylic ac copolymers (Eudragit's) by contact with multivalent ions such as calcium ions.
Abstract: Compositions, methods for preparing and methods of using air-filled polymeric microcapsules for ultrasound imaging are disclosed. Air-encapsulating microcapsules are formed by ionotropically gelling synthetic polyelectrolytes such as poly(carboxylatophenoxy)phosphazene, poly(acrylic acid), poly(methacrylic acid) and methacrylic acid copolymers (Eudragit's) by contact with multivalent ions such as calcium ions. In the preferred embodiment, the average size of the microcapsules is less than seven μm so that they are suitable for injection intravenously. The polymeric microcapsules are stable to imaging and display high echogenicity, both in vitro and in vivo. Due to their in vivo stability their potential application is extended beyond vascular imaging to liver and renal diseases, fallopian tube diseases, detecting and characterizing tumor masses and tissues, and measuring peripheral blood velocity. The microcapsules can optionally be linked with ligands that minimize tissue adhesion or that target the microcapsules to specific regions.
143 citations
TL;DR: Spectrometrie FTIR des melanges du copolymere ethylene/acide methacrylique avec le polymethylvinylether ou le copolyme oxyde d'ethylene/oxyde de propene as mentioned in this paper.
Abstract: Spectrometrie FTIR des melanges du copolymere ethylene/acide methacrylique avec le polymethylvinylether ou le copolymere oxyde d'ethylene/oxyde de propene
141 citations
TL;DR: In this article, the effect of different types and levels of plasticizers on the thermal and physical-mechanical properties of equilibrated methacrylic acid copolymers was studied.
141 citations