Methacrylic anhydrides

Synthesis. Functionalized monomers (and oligomers) of sebacic acid (SA-Me2) and 1,6 -bis(/ -carboxyphenoxy)hexane (CPH-Me2) were synthesized and subsequently photopolymerized as illustrated in Figure 1. First, the dicarboxylic acid was converted to an anhydride by heating at reflux in methacrylic anhydride for several hours. The dimethacrylated anhydride monomer was subsequently isolated and purified by dissolving in methylene chloride and precipitation with hexane. Infrared spectroscopy (IR), nuclear magnetic resonance (NMR) spectroscopy, and elemental analysis results indicated that both acid groups were converted to the anhydride, and the double bond of the methacrylate group was clearly evident. 

Figure 11 Schematic representation of poly (methyl methacrylate -co- methacrylic acid -co- methacrylic anhydride).

Hill etal. (2001) modified wood surfaces with methacrylic anhydride and grafted the activated surface with styrene in order to see if this would improve the UV stability of the modified substrate. There was no evidence to suggest that UV stability was improved either by chemical modification or by modification plus grafting. 

Hill and (letin (2000) modified the surfaces of wood veneers with methacrylic anhydride (Figure 6.6a) and formed lap joints using either styrene or methyl methacrylate in the presence of the free radical initiator azoisobutyronitrile. Significant improvements in bond strength were found when compared to unmodified wood. 

Figure 6.6 Structures of methacrylic anhydride (a) and crotonic anhydride (b).

Methacrylated sebacic acid monomer (MSA) was synthesized from se-bacic acid (Aldrich) and methacrylic acid (Aldrich). Sebacic acid was stirred in 1.2 equivalents of methacrylic anhydride at 80°C until dissolution (approximately 1 hour). The excess methacrylic anhydride and methacrylic acid by-product were removed by rotary evaporation at 65°C. The MSA was subsequently precipitated in anhydrous petroleum ether from a... 

Carbosilane methacrylate oligomers were prepared in a two-step process. Initially a di-allyloxy intermediate was methacrylated using methacrylic anhydride to introduce a thermal crosslinker. Hydrosilation of this product was performed using chloroplatinic acid and sym-divinyltetramethyldisiloxane with 1,3- or 1,4-bis-dimethylsilylbenzene. The cationic photoinitiator diphenyl iodonium hexafluorophosphate was used to polymerize all blended compositions. 

A mixture consisting of glycerol diallyl ether (0.17 mol), methacrylic anhydride (0.19 mmol), triethylamine (0.17 mol), 4-dimethylaminopyridine (8.6 mmol), and 70 ml THF was stirred at ambient temperature for 4 hours. It was then treated with additional... 

The step 1 product (0.11 mol), 4-dimethylaminopyridine (0.06 mmol), hydroquinone (0.35 g), and triethylamine (0.375 mol) were added to 275 ml dry acetone and then treated with methacrylic anhydride (0.14 mol). The mixture was refluxed for 90 minutes while the reaction progess was monitored by thin-layer chromatography. Since some hydroxyl starting material still remained, an additional 5 ml of methacrylic anhydride was added and the mixture refluxed an additional hour. Once the reaction was completed, the solution was cooled to ambient temperature and a yellow solid isolated. The solution was further treated with 100 ml cold methanol to further precipitate the product. The material was collected, washed with cold methanol, air dried, and 78.3% product isolated with a 96% purity. 

A reactor was charged with the step 3 product and mixture (64.9 g), methacrylic anhydride (36.0 g), methanesulfonic acid (5.3 g), and 325 ml toluene and then heated to 90°C for 3 hours. The mixture was then added to aqueous and treated with 500 ml of toluene. The organic layer was isolated and then washed with brine and additized with phenothiazine (0.33 g) and then concentrated and 63.2 g of product isolated as a colorless liquid. Analysis indicated it was a mixture of four isomers in an isomeric ratio of Isomer 1 (preferred) Isomer 2 Isomer 3 Isomer 4 of 38 34 17 11, respectively. 

A solution of methacrylic anhydride (0.03 mol) dissolved in 100 ml of chloroform was added dropwise to an ice-cooled solution of (ethylenedioxy)bis(ethylamine)... 

THE PREPARATION OF METHYL METHACRYLATE/ METHACRYLIC ANHYDRIDE COPOLYMERS FROM PMMA AND DIALKYL AMINES VIA REACTIVE EXTRUSION... 

The results of analysis of the samples prepared via reactive extrusion of PMMA with dimethylamine are shown in Tables 1 and 2, and Figure 1. It is apparent from these results that the main product of the reaction was methacrylic anhydride, confirming the hypothesis that alkyl-oxygen cleavage was involved in the reaction of PMMA with amines (at least with dimethylamine). However, additional subtleties of the reaction are apparent from a more detailed analysis of the reaction products vs. degree of conversion and reaction conditions. 

Polymerization of ethylene oxide with an acetal-protected alkoxide afforded a-aldehyde-co-methacryloyl PEO macromonomer, 17, after termination with methacrylic anhydride followed by acid hydrolysis [24]. 

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