Methacrylonitrile methacrylate with

The incorporation of small percentages (<10%) of 3-oximino-2-butanone methacrylate (4) into poly(methyl methacrylate) (PMMA) (Scheme I) results in a four fold increase in polymer sensitivity in the range of 230-260 nm flO.l 11. Presumably, the moderately labile N-O bond is induced to cleave, leading to decarboxylation and main chain scission (Scheme II). The sensitivity is further enhanced by the addition of external sensitizers. Also, preliminary results indicated that terpolymerization with methacrylonitrile would effect an additional increase. These results complement those of Stillwagon (12) who had previously shown that copolymerization of methyl methacrylate with methacrylonitrile increased the polymer s sensitivity to electron beam irradiation. The mole fraction of the comonomers was kept low in order to insure retention of the high resolution properties of PMMA (3.41. 

Fig. 22. Polymerization of methacrylonitrile (MAN) with the living prepolymer of methy] methacrylate (MMA) (2)-methylaluminum bis(2,6-di-tert-butyl-4-methylphenolate) (3e) system [MAN]o/[2]o=50, [2]o=22.6 mM, CH2CI2 as solvent, rt, initial ratios of 3e to 2=3.0 ( ), 4.0 (A), and 10 ( ). Effect of the amount of Lewis acid 3e on the rate of polymerization...

Table 7. Block copolymerization of methacrylonitrile (MAN) with the living prepolymer of methyl methacrylate (MMA) (2) in the presence of methylaluminum bis(2,6-di-ferf-butyl-4-methylphenolate) (3e) ... 

Hummel et al. (1967) also conducted brief studies of a number of other monomers. Chloroprene behaved simibrly to styrene. Methacrylonitrile behaved somewhat like methyl methacrylate with a definite gel effect. Butyl methacrylate behaved somewhat like styrene but with two small maxima in the rate-conversion curves tbc reasons for this arc unknown but the second small peak could arise from the gel effect. Decyl methacrylate showed only one maximum rate at about 50% conversion. Again the reasons for this behavior are unclear. Isoprene did not polymerize in emulsion at either low or high dose rates. Kaly in et al. (197S) have presented a study of the radiatiorr-induced polymerization of vinyl fiuoride in emulsion. 

Asymmetric hydrocarboxylation of methyl methacrylate with carbon monoxide/methanol under rather mild conditions in the presence of a chiral palladium catalyst palladium(II) chloride/Diop or DIPHOL gives up to 99% yield of dimethyl methylsuccinatc with up to 49% ee12 29. Hydrocarboxylation of methacrylonitrile is not achieved under similar conditions, but methacrylamide (using Diop) gives 61 % yield of methylsuccinimide with 37% ee29. 

Butyl alcohol is employed as a feedstock in Japan to make methyl methacrylate monomer. In one such process (26), the alcohol is oxidized (in two steps) to acryHc acid, which is then esterified with methanol. In a similar process (27), /-butyl alcohol is oxidized in the presence of ammonia to give methacrylonitrile [126-98-7]. The latter is hydrolyzed to methacrjiamide [79-39-0] which then reacts with methanol to yield methyl methacrylate [80-62-6]. 

Block copolymerization was carried out in the bulk polymerization of St using 18 as the polymeric iniferter. The block copolymer was isolated with 63-72 % yield by solvent extraction. In contrast with the polymerization of MMA with 6, the St polymerization with 18 as the polymeric iniferter does not proceed via the livingradical polymerization mechanism,because the co-chain end of the block copolymer 19 in Eq. (22) has the penta-substituted ethane structure, of which the C-C bond will dissociate less frequently than the C-C bond of hexa-substituted ethanes, e.g., the co-chain end of 18. This result agrees with the fact that the polymerization of St with 6 does not proceed through a living radical polymerization mechanism. Therefore, 18 is suitably used for the block copolymerization of 1,1-diubstituted ethylenes such as methacrylonitrile and alkyl methacrylates [83]. 

The low reactivity of a-olefins such as propylene or of 1,1-dialkyl olefins such as isobutylene toward radical polymerization is probably a consequence of degradative chain transfer with the allylic hydrogens. It should be pointed out, however, that other monomers such as methyl methacrylate and methacrylonitrile, which also contain allylic C—H bonds, do not undergo extensive degradative chain transfer. This is due to the lowered reactivity of the propagating radicals in these monomers. The ester and nitrile substituents stabilize the radicals and decrease their reactivity toward transfer. Simultaneously the reactivity of the monomer toward propagation is enhanced. These monomers, unlike the a-olefins and 1,1-dialkyl olefins, yield high polymers in radical polymerizations. 

Poly(methyl methacryIate-co-3-oximino-2-butanone methacrylate) (P(M-OM) and poly(methyl methacrylate-co-3-oximino-2-butanone-methacrylate-co-methacrylonitrile) (P(M-OM-CN)) were dissolved in methoxyethyl acetate (10% solution). Where appropriate, the specified amount of sensitizer was added to the solutions before coating onto a silicon substrate with a Headway Research spinner. Films were prebaked at 120 C for 60 min. 

In an effort to improve PMMA s photosensitivity further, methyl methacrylate has been copolymerized with higher percentages of the a-keto-oxime methacrylate and terpolymerized with varying amounts of methacrylonitrile. The resulting effects on resist properties, e.g., sensitivity, contrast and resolution, and plasma resistance, are reported here. The terpolymers are up to 85 times more sensitive than PMMA, and retain its high resolution characteristics. 

The photosensitivity of PMMA is significantly enhanced by the incorporation of 10 to 40 mole% 3-oximino-2-butanone methacrylate. Terpolymerization with methacrylonitrile increases that sensitivity still further, P(M-OM-CN) (69 16 15) being 85 times more sensitive than PMMA on exposure to the full output of a 1000 watt mercury lamp. Upon addition of external sensitizers, this sensitivity may be increased by an additional factor of 2 to 3. The high resolution characteristics of PMMA have been retained and the polymers in question show good plasma resistance. 

Figure 2 shows survey Raman spectra of the hcmopolymers, poly(methyl methacrylate)(PMMA.), poly(3-oximino-2-hutannone methacrylate)(pom), and poly(methacrylonitrile)(PMAN), and one terpolymer(P(M-0M-CN)) with a S/N ratio of about 10 1. Each of the polymers has a band specific to that polymer 8l2 dcm-1 (vg (C-O-C) for IMMA), 1622 hem" (Vg(C=N) for POM), and 2237 dcm l(vg(CHN) for PMAN). Additionally, there is an asymmetric C-H bending mode at 1 53 Acm l, common to all three homopolymers, which serves as an internal standard. These bands are indicated by arrows in Figure 2. A broad fluorescence background is evident, but it can be reduced to acceptable levels by exposure to high laser power for 10-30 minutes, depending on the sample. Residual background fluorescence may be due to the oximino chromophore itself. Figure 3 depicts an example of actual data for a 75 15 10 terpolymer with a S/N ratio of about 50 1.

Compared with propene, the oxidation of isobutene is more rapid but less selective, yet selectivities of over 75% appear feasible. Combustion is the main side reaction. One would expect that some considerable attention would be shown in the literature to isobutene oxidation as a route to the industrially important methacrylic acid, but this is not the case. Nor is it with the production of methacrylonitrile, analogous to the propene ammoxidation. Only in the patent literature is a high activity noticeable. 

Ammoxidation, a vapor-phase reaction of hydrocarbon with ammonia and oxygen (air) (eq. 2). can be used to produce hydrogen cyanide (HCN), acrylonitrile, acetonitrile (as a by-product of acrylonitrile manufacture), methacrylonitrile, benzonitrile, and toluinitriles from methane, propylene, butylene, toluene, and xylenes, respectively. See also Acrylonitrile and Methacrylic Acid and Derivatives,... 

One of the first detailed studies on these systems was that of Beaman (26), who showed that methacrylonitrile polymerizes by an anionic chain mechanism when treated with various bases, including Na in liquid ammonia at —75° C. He noted also that low molecular weight polymers are obtained from reaction of acrylonitrile with butylmagnesium bromide. Foster (56) extended the liquid ammonia method to copolymerization studies in which acrylonitrile was combined with styrene, with methyl methacrylate and with vinyl butyl sulfone. Satisfactory data were obtained only with the sulfone, in which case there was some tendency for alternation. 

Wooding and Higginson (94) have polymerized acrylonitrile, methyl methacrylate, styrene and butadiene with a wide variety of alkoxides and other basic materials. The ease of polymerization of monomer is in the above mentioned order. A further study of the polymerization of acrylonitrile by Zilka, Feit, and Frankel using alkoxides has also been reported (104). These workers also studied the polymerization of acrylonitrile and methacrylonitrile in dimethyl-formamide by aqueous quaternary ammonium hydroxides (106). 

The polar monomers cited include acrylic acid, acrylic esters, meth-acrylic acid, methacrylic esters, acrylonitrile, methacrylonitrile, acrolein, and vinyl acetate. While this list is reasonable, it also includes vinyl halides and vinylidene halides, although no examples with the latter are given. In view of the fact that the vinyl and vinylidene halides do not form complexes with Friedel-Crafts catalysts, these monomers would not be expected to be operable, as demonstrated by the results of Imoto (30). 

Methyl methacrylate (Fig. 1-4) and methacrylonitrile (6-5) are allylic-type monomers that do yield high molecular weight polymers in free radical reactions. This is probably because the propagating radicals are conjugated with and stabilized to some extent by the ester and nitrile substituents. The macroradicals are... 

Methacrylomtrile. a similar reaction in which methacrylonitrile (0.13 mole) was present instead of methyl methacrylate yielded gas containing 0.22% propane and 28.73% propylene. The upper layer which formed on adding the aqueous solution to 1 liter acetone was decanted. Adding ethanol to the oily bottom layer precipitated a solid which was collected on a sintered glass filter, washed with ethanol and ether, and air dried. The infrared spectrum of the reddish solid exhibited cyanide... 

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