Methacrylic anhydride, reaction with

A hydroxy-terminated oligomer can be converted into a carboxy-terminated one by reaction with an anhydride [37]. Such an oligomer can also be used to synthesize a methacrylated rubber as above [38]. 

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. 

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. 

The reactivity of 4,6-benzo[/ ][l,7]naphthyridine in Diels-Alder reactions with maleic acid and dimethyl acetylenedicarboxylate was examined. The reaction afforded adduct 332 (1996MI5). 6-Ethoxycarbonyl- 333a and phenacylmethylides 333b were used as 1,3-dipolar reagents in reactions with methacrylic acid, methyl methacrylate, butyl vinyl ether, methyl vinyl ketone, maleic anhydride and dimethyl acetylenedicarboxylate (1996MI5, 1999AJC149). 

Figure 4.4 Capping Reaction of Poly(phenylene ether) with Methacrylic Anhydride...

Unsaturated moieties can be introduced by the reaction of the hydroxyl groups of PPE with methacrylic anhydride. The reaction is conducted in a toluene solution. 4-Dimethylaminopyridine or 4-dimethylbut-ylamine serves as a catalyst.The capping reaction is shown in Figure 4.4. 

Figure 4.4 Capping reaction of poly(phenylene ether) with methacrylic anhydride.

Thus telechelic copolymers with terminal methacrylate groups were prepared by reaction of PPE-MM-B with methacrylic anhydride. This material is designated by the acronym PPE-MM-D and a generic structure is shown in Figure 2. 

Ahyl alcohol undergoes reactions typical of saturated, aUphatic alcohols. Ahyl compounds derived from ahyl alcohol and used industriahy, are widely manufactured by these reactions. For example, reactions of ahyl alcohol with acid anhydrides, esters, and acid chlorides yield ahyl esters, such as diahyl phthalates and ahyl methacrylate reaction with chloroformate yields carbonates, such as diethylene glycol bis(ahyl carbonate) addition of ahyl alcohol to epoxy groups yields products used to produce ahyl glycidyl ether (33,34). 

As previously discussed, solvents that dissolve cellulose by derivatization may be employed for further functionahzation, e.g., esterification. Thus, cellulose has been dissolved in paraformaldehyde/DMSO and esterified, e.g., by acetic, butyric, and phthalic anhydride, as well as by unsaturated methacrylic and maleic anhydride, in the presence of pyridine, or an acetate catalyst. DS values from 0.2 to 2.0 were obtained, being higher, 2.5 for cellulose acetate. H and NMR spectroscopy have indicated that the hydroxyl group of the methy-lol chains are preferably esterified with the anhydrides. Treatment of celliflose with this solvent system, at 90 °C, with methylene diacetate or ethylene diacetate, in the presence of potassium acetate, led to cellulose acetate with a DS of 1.5. Interestingly, the reaction with acetyl chloride or activated acid is less convenient DMAc or DMF can be substituted for DMSO [215-219]. In another set of experiments, polymer with high o -celliflose content was esterified with trimethylacetic anhydride, 1,2,4-benzenetricarboylic anhydride, trimellitic anhydride, phthalic anhydride, and a pyridine catalyst. The esters were isolated after 8h of reaction at 80-100°C, or Ih at room temperature (trimellitic anhydride). These are versatile compounds with interesting elastomeric and thermoplastic properties, and can be cast as films and membranes [220]. 

Electrophilic addition reactions. See also Addition reactions with butylenes, 4 405-408 of maleic anhydride, 75 490 with methacrylic acid/derivatives, 76 236-237 of propylene, 20 774 Electrophilic aromatic substitution, benzene, 3 599-601 Electrophilic attack, at nitrogen and carbon, 27 98... 

Elastomers with reactive end groups such as maleic anhydride (MA) or glycidyl methacrylate (GMA) are preferred for toughening PET. The reason that they are so effective is that they form a graft copolymer by reaction with the PET hydroxyl and carboxyl end groups (as shown below). The graft copolymer then acts as an emulsifier to decrease the interfacial tension and reduce the tendency... 

Butyl methacrylate, lauryl methacrylate, and cetyl methacrylate were combined with maleic anhydride, lauryl mercaptan, and process oil and then charged into a 2-liter reaction vessel equipped with two mixing impellers rotated at 300 rpm during the reaction. The mixture was preheated to 85°C and then treated with 2,2 -azoisobutyronitrile and heated for 4 hours at 85°C followed by 1 hour at 100°C. In some cases additional oil was added to make the product more easily pourable. Unreacted maleic anhydride and other low-molecular-weight products were removed by heating the reaction mass to 120°C while applying a vacuum. Reaction scoping results are provided in Table 1. 

Figure 9. Reaction of lignin with methacrylyl chloride and methacrylic anhydride [adapted from ( 5)].

Hydroxydiamantane (9.8 g), methacrylic anhydride (3.7 g), and 0.5 g of 18M H2SO4 were dissolved in 150 ml of toluene and refluxed for 2 hours. The reaction solution was then washed with aqueous NaHC03, dried using Na2S04, and concentrated. The residue was purified by column chromatography, and 6.3 g of product were isolated. 

Hydrolysis of styrene-methacrylic anhydride copolymers. One gram samples of the copolymers were suspended in distilled water (150 ml.) and the mixtures were refluxed, with stirring, until solutions were obtained that were stable at room temperature. Copolymers with high styrene contents hydrolyzed slowly and required 108 hr. reaction times. These polymers formed soap-like solutions when completely hydrolyzed. The hydrolyzed polymers were isolated by freeze-drying and were examined by infrared spectroscopy to establish the completeness of hydrolysis. 

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