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Methacrylic Anhydride (methacrylic + anhydride)
Selected AbstractsThermolyzable polymer networks and star polymers containing a novel, compact, degradable acylal-based dimethacrylate cross-linker: Synthesis, characterization, and thermolysisJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 24 2007Efrosyni Themistou Abstract A compact, cleavable acylal dimethacrylate cross-linker, 1,1-ethylenediol dimethacrylate (EDDMA), was synthesized from the anhydrous iron(III) chloride-catalyzed reaction between methacrylic anhydride and acetaldehyde. The ability of EDDMA to act as cross-linker was demonstrated by using it for the preparation of one neat cross-linker network, four star polymers of methyl methacrylate (MMA), and four randomly cross-linked MMA polymer networks using group transfer polymerization (GTP). For comparison, the corresponding polymer structures based on the commercially available ethylene glycol dimethacrylate (EGDMA) cross-linker (isomer of EDDMA) were also prepared via GTP. The number of arms of the EDDMA-based star polymers was lower than that of the corresponding EGDMA polymers, whereas the degrees of swelling in tetrahydrofuran of the EDDMA-based MMA networks were higher than those of their EGDMA-based counterparts. Although none of the EDDMA-containing polymers could be cleanly hydrolyzed under basic or acidic conditions, they could be thermolyzed at 200 °C within 1 day giving lower molecular weight products. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5811,5823, 2007 [source] Stability of photocurable anhydrides: Methacrylic acid mixed anhydrides of nontoxic diacidsJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 24 2001Peter J. Tarcha Abstract Disproportionation of the liquid mixed anhydride dimethacrylic sebacic anhydride (m-SA) to methacrylic anhydride and polyanhydride oligomers, as well as vinylic polymerization, can occur on workup and storage at room temperature. Dimethacrylic 1,3-bis(p -carboxyphenoxy) propane, being a solid, can also disproportionate, but the propensity to do so is lower than for m-SA. These events can be suppressed with free-radical inhibitors, and the inhibitor 2+3- t -butyl-4-methoxyphenol is a more effective stabilizer than 4-methoxyphenol at 20 °C. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 4189,4195, 2001 [source] Structure and Properties of Poly(, -caprolactone) Networks with Modulated Water UptakeMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 23 2006Jorge L. Escobar Ivirico Abstract Summary: A PCL macromonomer was obtained by the reaction of PCL diol with methacrylic anhydride. The effective incorporation of the polymerizable end groups was assessed by FT-IR and 1H NMR spectroscopy. PCL networks were then prepared by photopolymerization of the PCL macromonomer. Furthermore, the macromonomer was copolymerized with HEA, with the aim of tailoring the hydrophilicity of the system. A set of hydrophilic semicrystalline copolymer networks were obtained. The phase microstructure of the new system and the network architecture was investigated by DSC, IR, DMS, TG, dielectric spectroscopy and water sorption studies. The presence of the hydrophilic units in the system prevented PCL crystallization on cooling; yet there was no effect on the glass transition process. The copolymer networks showed microphase separation and the , relaxation of the HEA units moved to lower temperatures as the amount of PCL in the system increased. Ideal structure, compatible with the experimental results, for the hydrophilized poly(, -caprolactone) networks with modulated water uptake. [source] Cross-Linked Poly(, -caprolactone/D,L -lactide) Copolymers with Elastic PropertiesMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 18 2002Antti O. Helminen Abstract Cross-linked , -caprolactone (CL) and D,L -lactide (DLLA) copolymers with elastic properties were synthesized in three steps. First, the monomers were copolymerized in ring-opening polymerization to obtain telechelic star-shaped oligomers with almost completely random monomer distribution. The oligomers were methacrylated with methacrylic anhydride in the second step and cured in a third. Molar CL/DLLA compositions of 30/70, 50/50, 70/30, 90/10, and 100/0 were used to obtain elastic structures with a wide range of properties. The effect of the average length of the copolymer block on the properties of the networks was evaluated with three different co-initiator contents (0.5, 1.0, and 2.0/100) in the oligomer synthesis. The oligomers were characterized by 13C NMR spectroscopy, size-exclusion chromatography (SEC), and differential-scanning calorimetry (DSC). The formation of elastic networks was confirmed by the absence of a flow region in dynamic mechanical analysis (DMA), the increase in Tg in DSC, and the full recovery of the sample dimensions after tensile testing. In addition, gel contents were high and the samples swelled in CH2Cl2. The networks possessed break stresses from 0.7,9.7 MPa with elongations from 80,350%. Networks with 100 or 90% of , -caprolactone retained their form in vitro for 12 weeks, but an increase in lactide content made the networks more vulnerable to hydrolysis. Water absorption of the polymers during hydrolysis. [source] | ||||||||||