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.

Enteric coated soft capsules and method of preparation thereof

Abstract: Soft capsules coated with an enteric coating comprising a 1:1 copolymer of methacrylic acid and methyl or ethyl acrylate or methyl or ethyl methacrylate and a plasticizer without need for a subcoating and optionally additionally coated with a protective coating comprising hydroxypropyl methylcellulose or hydroxypropyl cellulose or a mixture thereof and a plasticizer and method of preparation thereof are disclosed.

Magnetic solid‐phase extraction using magnetic hypercrosslinked polymer for rapid determination of illegal drugs in urine

Abstract: A novel magnetic material Fe(3)O(4)/SiO(2)/P(MAA-co-VBC-co-DVB) was prepared via the hypercrosslinking of its precursor which was produced via precipitation polymerization of methacrylic acid (MAA), vinylbenzyl chloride (VBC), and divinylbenzene (DVB) in the presence of Fe(3)O(4)/SiO(2) submicrospheres with the surface containing abundant reactive double bonds. The resultant sorbent was characterized by scan electron microscopy, N(2) adsorption, and Fourier transform infrared spectroscopy. It was found that this material had remarkable features such as large surface area (500 m(2)/g) and pore volume (0.32 cm(3)/g), as well as desirable chemical composition (including hydrophobic and ion-exchange moieties). Taking advantages of the Fe(3)O(4)/SiO(2)/P(MAA-co-VBC-co-DVB), a magnetic SPE (MSPE) coupled with capillary electrophoresis (CE) method was developed for the determination of illegal drugs in urine samples. The extraction time could be clearly shortened up to 3 min. The recoveries of these drug compounds were in the range of 84.0-123% with relative standard deviations ranging between 1.7 and 10.5%; the limit of detection was in the range of 4.0-6.0 μg/L. The proposed method is simple, effective, and low-cost, and provides an accurate and sensitive detection platform for abused drug analysis.

Hyperbranched polyesters and their application in dental composites: monomers for low shrinking composites

Abstract: Using trimethylolpropane (TMP) and 2,2-bishydroxymethylpropionic acid (Bis-MPA), aliphatic hyperbranched polyesters (HBP) were synthesized, with a degree of branching of DB = 0.47 and a degree of polymerization of Pn = 16.5. Aromatic HBPs with repetitive units of 2,2-bis(4-hydroxyphenyl)pivalonic acid (Bis-PVA) lead to a higher DB = 0.48 and Pn = 30.5 compared to the aliphatic HBP. Reactive functionalization of the hyperbranched polymers was achieved via esterification of mixtures of methacrylic acid and carboxylic acids. In this manner, i-butyric acid and methacryloyl terminated HBPs were obtained. They have a low viscosity ranging from 200 to 364 Pa*s and exhibit relatively low volume shrinkage (1.9 to 3.6%) during photoinitiated cure. Dental composites with volume shrinkage of 0.5 to 1.5% have been prepared using these methacryloyl terminated HBPs in combination with a Ba/alumosilicate glass filler. Copyright © 2001 John Wiley & Sons, Ltd.

Uniform molecularly imprinted poly(methacrylic acid) nanospheres prepared by precipitation polymerization: the control of particle features suitable for sustained release of gatifloxacin

Abstract: Herein we have combined the molecular imprinting technique and thermally-initiated precipitation polymerization to develop novel molecularly imprinted poly(methacrylic acid) nanospheres (PMAA MIPNs) for sustained release of gatifloxacin (GFLX). In the process, ethylene glycol dimethacrylate (EGDMA) and GFLX were used as the cross-linker and template, respectively. The effects of reaction medium and concentration of the monomers such as MAA, EGDMA and GFLX were systematically investigated. Uniform nanospheres with diameter equal to 136.0 ± 8.1 nm and particle dispersion index (PDI) equal to 1.01 were obtained when the total monomer concentration was 1 vol%, the EGDMA content was 70 mol% and the GFLX/MAA ratio was 1 : 15 (mol/mol). The drug loading profiles and in vitro release studies indicated that PMAA MIPNs are better drug delivery vessels and have an improved release profile than non-imprinted ones, which was attributed to the reinforced interaction between GFLX and PMMA side groups due to the specific GFLX molecular arrangement in the PMAA polymeric matrix. Based on these results, these novel PMAA MIPNs are a promising candidate for sustained release of GFLX.