Methacrylic anhydride preparation

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. 

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. 

Methacrylic anhydride in pyridine, applied to 1,6-anhydro-D-glucose 2,4-phenylboronate, gave the 3-methacrylate, from which an addition polymer was prepared.78... 

In the cyclopolymerization of methacrylic anhydride(MA) as a typical 1,6-diene, five- and six-membered ring anhydride structures can be formed, respectively corresponding to intramolecular hh and ht addition of uncyclized radical. The IR spectrum of poly-MA has been tentatively compared earlier with that of poly-MA prepared by dehydration of poly(methacrylic acid)(37) no five-membered cyclized anhydrides were detected, any absorption at higher frequency due to the strain of a five-membered ring being absent. 

Methacrylic anhydride was prepared from methacroyl chloride and either sodium methacrylate (14) or methacrylic acid (15). The relative intensity of resonance observed at 6=11.6 ppm in the nmr spectrum of this monomer and the intensity of carbonyl absorption observed at 1700 cm-1, relative to that observed at 1724 and 1782 cm-1 Indicated that the monomer had less than 3 mole percent methacrylic acid. For the most part, monomer used for copolymerization experiments, b.p. 50° (1 mm), was prepared from sodium methacrylate. It contained less than one mole percent methacrylic acid ... 

Figure 1. Olefinic proton resonances of styrene-methacrylic anhydride copolymers containing both uncycttzed methacrylic anhydride units and absorbed monomer (top), and uncyclized methacrylic anhydride units but little absorbed monomer (bottom). This sample was prepared by reacting a styrene-methacrylic acid copolymer with methacrylic anhydride.

Table I lists compositions determined this way for styrene-methacrylic anhydride copolymers prepared at 40°.

Compositions of Styrene-Methacrylic Anhydride Copolymers Prepared at 40°... 

B - 6 2.7-3.2 ppm and C - 6 = 2.2-2.7 ppm). Figure 2 compares the aliphatic proton resonance patterns of styrene-MMA copolymers prepared by direct polymerization and by modification of styrene-methacrylic anhydride copolymers. The methoxy and a-methyl proton resonance patterns of the copolymers differ considerably even though they have similar compositions. The proportions of MeO resonance occurring in the A- and B- areas (FAi Fg) were calculated by dividing the A- and B- resonance areas by the total MeO resonance area expected, based on the compositons of the copolymers (i.e., MeO resonance area expected = 3/8 x % MMA/100). The proportion of MeO resonance occurring in the C- area was calculated by subtracting these quantities from one (Fq = 1 - Fa - Fg). 

Figure 2. Aliphatic proton resonance (100 MHz) of styrene-methyl methacrylate copolymers in CeD9 solution at 80°C containing 49 mol % of styrene derived from a styrene-methacrylic anhydride copolymer (top), and containing 56 mol % styrene prepared directly from styrene and methyl...

In many samples, no resonances due to uncyclized anhydride units were detected. This was particularly true of copolymers with high styrene contents. Table I lists the compositions determined for styrene-methacrylic anhydride copolymers prepared at 40°. The styrene contents of the copolymers are in good agreement with those reported by Smets, et al., for copolymers prepared from comparable monomer ratios, but where the anhydride concentration was 2M. However, Smets, et al. report that 30-50 percent of the anhydride units were uncyclized in their copolymers and it appears that the extent of cyclization is better than 90 percent, generally about... 

Smets, et al. (12) noted that the compositions of styrene-methacrylic anhydride copolymers prepared from given styrene-methacrylic anhydride mixtures were independent of the amount of solvent present in the system and concluded that ri and r3 in the kinetic scheme outlined above must be equal. This conclusion, which was also accepted by Baines and Bevington (13), enabled reactivity ratios for this copolymerization system to be calculated by use of the standard copolymer equation. Unfortunately, this is not a valid conclusion the results in Table II show that for conditions similar to those employed in the previous work, the styrene contents of the copolymers are imperceptibly affected by dilution of the system, even when r3 is five times greater or less than ri. 

Figure 3. Mole fraction of styrene units in styrene-methyl methacrylate copolymers %S (S/MMA) derived from styrene-methacrylic anhydride copolymers, as a function of the molar percentage of styrene (% S,) in the monomer mixture used to prepare the styrene-methacrylic anhydride copolymers. The solid line was calculated using rt = r, = 0.19, r, = 0.11, rc = 37 and rc = 7.7. Key O, 60°C polymerization and , 40°C polymerization.

Figure 4. HR-Plots of methoxy proton resonance data for styrene-methyl methacrylate copolymers derived from styrene-methacrylic anhydride copolymers prepared at 60°C. Key O, (FA-P(MMM))/P(SMS) vs. P(SMM + MMS)/P(SMS) V, Fb/P(CMS) vs. P(SMM + MMS)fP(SMS) , F /P(SMS) vs. P(SMM +...

Cyclic poly (methyl methacrylate) was prepared from a-carboxy,co-amino heterodifrmctional precursor obtained by a living anionic polymerization of methyl methacrylate using N,N-diphenylethylenediamine monolithium amide and succinic anhydride as an initiator and terminator, respectively. Its intramolecular cyclization was carried out to obtain a well-defined cyclic poly(methyl methacrylate). ... 

The Preparation of Methyl Methacrylate/Methacrylic Anhydride Copolymers from... 

Attempts to prepare H-H poly(methyl methacrylate) by radical cyclopolymerization of methacrylic anhydride and methacrylimides have given promising results (42). The cyclopolymerization must be directed to the exclusive formation of the unfavorable five membered ring intermediate. Cyclopolymers which consist of mixtures of five and six membered rings were obtained with five membered ring intermediates predominating (23,42,59). 

The reactivity ratios for styrene-aryl methacrylate copolymerizations [79 — 27] differ significantly from those for the styrene-MMA system, so that copolymers derived from the aryl methacrylate copolymers should have different structures (sequence distributions) than conventional styrene-MMA copolymers of equivalent composition. In the system used to prepare styrene-methacrylic acid copolymers [75], the monomer reactivity ratios are comparable to those of the styrene-MMA system, but the stereochemical structure of the conventional copolymers and of those derived from the methacrylic acid copolymers might be expected to differ. In addition, change of the copolymerization solvent can alter the reactivity ratios for the styrene-methacrylic acid system. Finally, styrene-MMA copolymers derived from styrene-methacrylic anhydride copolymers [22] were expected to have especially interesting structures. The tendency of the anhydride units to become incorporated into the copolymers as cyclic units is very high and there is a great tendency for styrene and cyclic anhydride units in the co-... 

The concept for preparing vinyl esters with maleate residues has also been investigated by using hydroxyalkyl or glycidyl acrylate and methacrylate starting materials. " " For example, phthalic anhydride was treated with hydroxyethyl methacrylate and the acid esterified with glycidyl methacrylate to prepare product 3. Compound 3 was treated with MA to obtain a resin 4... 

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. 

Kondo maintained his interest in this area, and with his collaborators [62] he recently made detailed investigations on the polymerization and preparation of methyl-4-vinylphenyl-sulfonium bis-(methoxycarbonyl) meth-ylide (Scheme 27) as a new kind of stable vinyl monomer containing the sulfonium ylide structure. It was prepared by heating a solution of 4-methylthiostyrene, dimethyl-diazomalonate, and /-butyl catechol in chlorobenzene at 90°C for 10 h in the presence of anhydride cupric sulfate, and Scheme 27 was polymerized by using a, a -azobisi-sobutyronitrile (AIBN) as the initiator and dimethylsulf-oxide as the solvent at 60°C. The structure of the polymer was confirmed by IR and NMR spectra and elemental analysis. In addition, this monomeric ylide was copolymerized with vinyl monomers such as methyl methacrylate (MMA) and styrene. 

The preparation of fluorinated alcohols was carried out in multistep routes according to the reported procedures.1012 The synthesis of acrylic and methacrylic esters as shown in Table 11.1 was carried out in a fluorocarbon solvent such as Freon 113 by the reaction of the respective fluorinated alcohol with acryloyl chloride or methacryloyl chloride and an amine acid acceptor such as triethyla-mine with examples shown in Scheme 1. Other attempts to esterify the fluoroalcohols directly with acrylic acid or acrylic anhydride were not successful.11 Product purification by distillation was not feasible because of the temperature required, but purification by percolation of fluorocarbon solutions through neutral alumina resulted in products of good purity identified by TLC, FTIR, and H-, 13C-, and 19F- FTNMRs. 

Poly methacrylates and copolymers of butadiene and methacrylate having /arious pyrimidine derivatives (Figures 1, and 2) were prepared by free radical polymerization of the methacrylate monomers (14-16). In the case of the poly(MAOT -alt-MAOT3Me )> the polymer was obtained by the reaction of the polymethacrylic anhydride with the hydroxyethyl... 

Fig. 1 Chemical structures of the polymers commonly used for preparation of beads poly (styrene-co-maleic acid) (=PS-MA) poly(methyl methacrylate-co-methacrylic acid) (=PMMA-MA) poly(acrylonitrile-co-acrylic acid) (=PAN-AA) polyvinylchloride (=PVC) polysulfone (=PSulf) ethylcellulose (=EC) cellulose acetate (=CAc) polyacrylamide (=PAAm) poly(sty-rene-Wocfc-vinylpyrrolidone) (=PS-PVP) and Organically modified silica (=Ormosil). PS-MA is commercially available as an anhydride and negative charges on the bead surface are generated during preparation of the beads...

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