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.

Method for the manufacture of reinforced, steam-cured light-weight concrete and a composition for carrying out the method

Abstract: A method for the manufacture of metal reinforced, steam-cured, light weight concrete where the metal reinforcement is provided with a protective coating thereon prior to being embedded in the concrete. The protective coating comprises an aqueous mixture of 60 - 90 percent by weight of Portland Cement, 10 - 50 percent of water, and 2 - 20 percent by weight of a copolymer selected from the group consisting of copolymers of acrylic acid ethyl ester, methacrylic acid methyl ester, methacrylic butyl ester, and methacrylic acid isobutyl ester.

Hydration of polyacids.

Abstract: The hydration of several polyacids has been investigated with special attention to the effects of neighboring charged groups and hydrophobic groups on the hydration regions. The molar volume change due to the structural change of water by the hydration was obtained by the method of refractivity measurement. The polyacids employed were poly(acrylic acid), poly(methacrylic acid), poly(L-glutamic acid), and a copolymer of maleic acid and vinyl acetate. The measurement of the refractive index was performed for the solutions of these polymers neutralized to varying degrees by tetrabutyl-ammonium hydroxide and sodium hydroxide. The results confirm the characteristics of the previous model of the hydration of polyelectrolytes, that is, the cooperative action of neighboring charged groups induce the second hydration region in addition to the intrinsic hydration region. The stiff structure of water in these regions restricts the mobility of counterions forced to enter into these regions by the strong electrostatic potential of polyions. The results indicate also that hydrophobic groups induce an additional hydration region around their neighboring charged groups. Small but negative volume changes were observed for conformational changes of poly(L-glutamic acid) and poly(methacrylic acid) induced by the neutralization of carboxyl groups.

Investigation on synthesis and properties of isosorbide based bis-GMA analogue.

Abstract: The aim of this work was to synthesize and investigate properties of a novel dimethacrylic monomer based on bioderived alicyclic diol—isosorbide. Its potential as a possible substitute of 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropoxy)phenyl]propane (BISGMA), widely used in dental restorative materials and suspected for toxicity was assessed. The novel monomer was obtained in a three-step synthesis. First, isosorbide was etherified by a Williamson nucleophilic substitution and subsequently oxidized to isosorbide diglycidyl ether (ISDGE). A triphenyl phosphine catalyzed addition of methacrylic acid to ISDGE resulted in 2,5-bis(2-hydroxy-3-methacryloyloxypropoxy)- 1,4:3,6-dianhydro-sorbitol (ISDGMA). The monomer obtained was photopolymerized using camphorquinone/2-(dimethylamino)ethyl methacrylate initiating system. Next, compositions with triethylene glycol dimethacrylate (TEGDMA) were prepared and polymerized. Double bond conversion, polymerization shrinkage and water sorption of resulting polymers were determined. Selected mechanical (flexular strength and modulus, Brinell hardness) and thermomechanical (DMA analysis) properties were also investigated. BISGMA based materials were prepared as reference for comparison of particular properties.