Methyl benzyl methacrylate

The tacticity has been estimated by N. M. R. analysis also in the case of poly - (1 - methyl-benzyl) -methacrylate (64) obtained by different polymerization processes (Table 18). 

The experimental data obtained by several authors who polymerized, by radical processes, optically active para-sec.butyl-vinyl benzoate (73), ortho-vinyl-benzyl-sec.butylsulfide (98), 1.3-dimethyl-butyl-methacrylate (9), and (l-methyl-benzyl)-methacrylate (14), confirmed the theoretical forecast. In fact the polymers obtained after cleavage of the optically active groups did not show optical activity. The stereoregularity of the polymers has not been carefully checked up and the possible increase in stereoregularity, which was theoretically foreseen, has not been reported. 

In fact, the copolymers of methacrylic acid with maleic anhydride (14) and the copolymers of vinyl alcohol with maleic anhydride (127) obtained respectively from optically active (l-methyl-benzyl)-methacrylate or (l-methyl-benzyl)-vinyl-ether and maleic anhydride, were optically active, but their rotatory power was rather small. 

Stereoselective polymerizations and copolymerizations of methacrylates have also been realized recently and are potentially of considerable importance. In the case of (RS)-a-methylbenzyl methacrylate with anionic catalysts and 2,3-epoxypropyl methacrylate with an optically active Grignard catalyst selective propagations appear to occur. Copolymerization of (RS)-a-methyl-benzyl methacrylate and methyl methacrylate also proceed stereoselectively. ... 

TiCU readily functionalizes hydrophilic polymers such as poly(vinyl alcohol), m-ciesol novolac and methacrylic acid copolymers as well as moderately hydrophobic polymers such as poly(methyl methacrylate), poly(vinyl acetate), poly(benzyl methacrylate) and fully acetylated m-cresol novolac. HCI4 did not react with poly(styrene) to form etch resistant films indicating that very hydrophobic films follow a different reaction pathway. RBS analysis revealed that Ti is present only on the surface of hydrophilic and moderately hydrophobic polymer films, whereas it was found diffused through the entire thickness of the poly(styrene) films. The reaction pathways of hydrophilic and hydrophobic polymers with HCI4 are different because TiCl is hydrolysed by the surface water at the hydrophilic polymer surfaces to form an etch resistant T1O2 layer. Lack of such surface water in hydrophobic polymers explains the absence of a surface TiC>2 layer and the poor etching selectivities. 

In this article we will describe two different types of positive electron-beam resists, which were briefly reported in our previous communications (2,3). One is the homopolymer or copolymer with methyl methacrylate and a-substituted benzyl methacrylate, which forms methacrylic acid units in the polymer chain on exposure to an electron-beam and can be developed by using an alkaline solution developer. In this case, the structural change in the side group of the polymer effectively alters the solubility properties of the exposed polymer, and excellent contrast between the exposed and unexposed areas is obtained. The other is a self developing polyaldehyde resist, which is depolymerized into a volatile monomer upon electron-beam exposure. The sensitivity was extremely high without using any sensitizer. 

The results mentioned here clearly indicate that the enhancement in the sensitivity and 7-value of the poly (a,a-dimethyl benzyl methacrylate) resist over poly(methyl methacrylate) is mainly due to facilitated formation of methacrylic acid units on electron-beam exposure. The exposed area, which contains CH,... 

Some of the polymers slowly change their helicity in solution. A chiral crown ether-potassium ferf-butoxide combined system was reported to cause polymerization of methyl, tert-butyl, and benzyl methacrylate to form isotactic polymers that had high rotation values (164). Detailed scrutiny, however, raised questions about the result (135, 165). At first, in the presence of the initiator, the oligomers exhibit considerable activity, but after removal of the catalyst, the optical activity decreases. This decrease may be attributed to unwinding of the helixes in the chain the helicity could be caused by the anchored catalyst. 

Optically active acrylic, chloro-acrylic and methacrylic esters of sec. butyl alcohol, 2-methyl-butyl alcohol, 1.3-dimethyl-butyl alcohol, 1-methyl-benzyl alcohol, bomeol and menthol have been polymerized mostly by radical mechanism (Tables 16, 17, 18). 

In agreement with the data on poly-a-olefins and poly-vinyl-ethers having the side chain asymmetric carbon atoms in the y-position with respect to the main chain, stereoregularity does not exert a remarkable influence on the rotatory power of poly-acrylates and poly-methacrylates. In fact, according to the quantitative data reported by H. Sobue, K. Matsuzaki, S. Nakano (135), and to the qualitative indications given by Liu, Szuty and Ullmann (64), concerning respectively poly-menthyl-meth-acrylate and poly-(l-methyl-benzyl)-methaciylate, the specific optical activity of the polymers does not vary by more than 30% when varying, within a wide interval, the isotactic triads content of the polymers (Table 18). 

Figure 5. SNMS depth profiles for a series of methacrylate polymer/Z6040 (<5 =9.3)/Al laminates. Profile a is fora laminate in which polyfisobutyl methacrylate) (d =8.65) was the polymer. Profiles b, c, and d utilized polyfethyl methacrylate) (<5 = 8.95), poly (methyl methacrylate) (i=9.3), and poly(benzyl methacrylate) (d = 9.9) as the polymer, respectively.

The data on kp and kt as reported in the literature differ considerably. Therefore, we conducted new studies on methyl methacrylate (MMA), benzyl methacrylate (BMA), and styrene (St) as monomers. The constants were obtained by applying the method of intermittent illumination (rotating sector) combined with stationary state methods. The viscosity of the solvents varied between 0.5 and 100 cP. No mixed solvents composed of low- and high-molecular components were used but pure solvents only, the molecules of which did not deviate very much from a spherical form (methyl formate, diethyl phthalate, diethyl malonate, dimethyl glycol phthalate, etc.). 

Helix-sense-selective polymerization of methyl, benzyl, and f-butyl methacrylates was attempted by using the complexes of chiral crown ethers, 91 and 92, and that of a chiral diamine 93 with n-BuLi however, these esters seem to be too small to form and maintain helical conformation [138,139], The complexes of BuLi with 58a and 59 failed in producing an optically active, helical polymer in the polymerization of methyl and benzyl methacrylates [104b]. 

Copolymeirization provides an unique approach to the synthesis of polyfunctional stabilizers. E.g. terpolymers of 4-isopropenyl-2,6-di-terr-butylphenol, methyl methacrylate and 2-(2-hydroxy-5-isopropenyl)-2H-benzotriazole or poly[4-(2,2,6,6-tetramethylpiperidyl) methacrylate-co-4-hydroxy-3,5-di-tert-butyl-benzyl methacrylate] (96), having M 5,400, posses properties of AO and LS [108]. 

Cp2TiCl2 has been assessed as additive that controls polymer chain growth in the polymerization of methyl methacrylate.1224 Methyl methacrylate is easily polymerized in the photopolymerization with Cp2TiCl2 in a water-methanol mixture under irradiation of a 15 W fluorescent room lamp. The polymerization proceeded heterogeneously.1225 This process in the presence of 2,2 -bipyridyl, 1,10-phenanthroline, or sparteine as the chelating reagent has been studied.1226 Similar studies on the polymerization of methacrylate monomers such as methyl methacrylate, ethyl methacrylate, phenyl methacrylate, and benzyl methacrylate at 40 °C have also been performed.1227 The results of co-polymerization of methyl methacrylate and acrylonitrile indicate that this process proceeds through a radical mechanism.1228 The mechanism of the controlled radical polymerization of styrene and methyl methacrylate in the... 

CCT of benzyl methacrylate leads to a mixture of poly(benzyl methacrylate) macromonomers from which the dimer macromonomer could be isolated.516 When the benzyl dimer is used as a RAFT chain-transfer agent, PMMA with a- and co-terminal benzyl methacrylate units is obtained. Catalytic hydrogenation of the a,co-benzyl terminal methyl methacrylate polymer results in the evolution of toluene and formation of a,co-dicarboxyl functional telechelic PMMA. 

Specifically mentioned monomers include methyl methacrylate, ethyl methacrylate, propyl methacrylates (all isomers), butyl methacrylates (all isomers), 2-ethylhexyl methacrylate, isobornyl methacrylate, methacrylic acid, benzyl methacrylate, phenyl... 

Schulz et al.12,13 estimated the elementary rate constants for methyl methacrylate in solvents whose viscosities varied by a factor of 170, indicating that the termination rate constants were inversely proportional to the viscosity of the solvents. The variation of propagation rate constants was much less than that of termination rate constants. They have also obtained similar results in the free radical polymerization of benzyl methacrylate. 

Figure 2. Conflict requirement between the sensitivity and dryetching durability in positive electron resists based on methacrylate polymers. Sputter etching rates were measured under the same conditions using CF, gas. Key 1, poly(p-methoxypheny1 methacrylate) 2, poly(phenyI methacrylate) (PPhMA) 3, poly(3-phenylpropyl meyhacrylate) 4, poly(benzyl methacrylate) 5, poly(p-methoxybenzyl methacrylate) 6, poly(p-fluorophenyl methacrylate 7, poly(trichloropheny1 methacrylate) 8, poly(methyl methacrylate) (PMMA) 9, poly(tert-buty1 methacrylate) 10, poly(ethyl methacrylate) 11, poly(isobutyl methacrylate) 12, poly(n-butyl methacrylate) (PnBMA) 13, poly(dimethyltetrafluoro methacrylate) (FPM) 14, poly(trichloromethyl methacrylate) (EBR-1) and 15, poly(hexafluorobutyl methacrylate) (FBM).

The polymers were synthesised from boc-protected amine monomers and alkyl or benzyl methacrylate monomers. The polymerisation was performed by applying AIBN, as a radical initiator, and methyl 3-mercaptopropionate, as a chain transfer agent, in acetonitrile. The treatment of boc-protected polymers with TFA produced amphiphilic random copolymers with cationic ammoninm groups in the side chains. 

On the other hand, the copolymerization of (S)-a-nieth benzyl methacrylate (Ml) and trityl methacrylate(M2) by Buli in toluene yielded a mixture of an isotactic polytiBr of Ml and a less stereoregular copdymer, similady to the copdy-merization of methyl methacrylate(Mi) and trityl methacrylate(M2) in this solvent. If the (RS)-monomer was used instead of (S)-isomer, only the copdymer of low stereoregularity was produced, althou it had a wide distribution as to the composition. The low reactivity of trityl methacrylate in the copdymerization even with (RS)-o-methylbenzyl methacrylate may be also attributed to the sterk hindrance due to the bulkiness of the trityl ester, since the homopdymerization of this monomra itself proceeded extremely slowly in toluene. ... 

Table 1 shows the Q and e values and the monomer reactivity ratios rj and T2 for the radical copolymerization process. Since the monomer reactivity ratios between negatively birefringent methyl methacrylate (MMA) and positively birefringent 2,2,2-trifluoroethyl methacrylate (3FMA) and benzyl methacrylate (BzMA) are nearly equal to unity, these monomers can be randomly copolymerized, resulting in homogeneous and transparent copolymers. 

Materials. Methyl methacrylate (MMA, 99%, Janssen Chimica), benzyl methacrylate (BzMA, 98%, TCI), and 2,2,3,3-tetrafluoropropyl methacrylate (4FMA, Echo Chemical Co.) were purified by vacuum distillation. PMMAl (Chi-Mei, Co., = 8.3x104, m = 4.0xl()4), PMMA2 (Asahi, DELPET 70H, M = 13x104, Mn = 8x104), 1-hydroxycyclohexyl phenyl ketone (HCPK, TCI) and... 

Electron-withdrawing substituents in anionic polymerizations enhance electron density at the double bonds or stabilize the carbanions by resonance. Anionic copolymerizations in many respects behave similarly to the cationic ones. For some comonomer pairs steric effects give rise to a tendency to altemate. The reactivities of the monomers in copolymerizations and the compositions of the resultant copolymers are subject to solvent polarity and to the effects of the counterions. The two, just as in cationic polymerizations, cannot be considered independently from each other. This, again, is due to the tightness of the ion pairs and to the amount of solvation. Furthermore, only monomers that possess similar polarity can be copolymerized by an anionic mechanism. Thus, for instance, styrene derivatives copolymerize with each other. Styrene, however, is unable to add to a methyl methacrylate anion, though it copolymerizes with butadiene and isoprene. In copolymerizations initiated by w-butyllithium in toluene and in tetrahydrofuran at-78 °C, the following order of reactivity with methyl methacrylate anions was observed. In toluene the order is diphenylmethyl methacrylate > benzyl methacrylate > methyl methacrylate > ethyl methacrylate > a-methylbenzyl methacrylate > isopropyl methacrylate > t-butyl methacrylate > trityl methacrylate > a,a -dimethyl-benzyl methacrylate. In tetrahydrofuran the order changes to trityl methacrylate > benzyl methacrylate > methyl methacrylate > diphenylmethyl methacrylate > ethyl methacrylate > a-methylbenzyl methacrylate > isopropyl methacrylate > a,a -dimethylbenzyl methacrylate > t-butyl methacrylate. 

UV absorber, PMMA 2-[2-Hydroxy-3,5-d i-( 1,1 -di methyl benzyl) phenyl]-2H-benzotri azole UV absorber, polishes Phenyl salicylate UV absorber, polyamide 2-[2-Hy d roxy-3,5-d i -(1,1 -d i methyl benzyl) phenyl]-2H-benzotri azole UV absorber, polyester Benzophenone-3 Bis [2-hydroxy-5-methyl-3-(benzotriazol-2-yl) phenyl] methane UV absorber, polyester dyed fabrics Benzophenone-1 UV absorber, polyesters Benzophenone-2 Benzophenone-6 Bis [2-hydroxy-5-t-octyl-3-(benzotriazol-2-yl) phenyl] methane Bumetrizole 4-Dodecyloxy-2-hydroxybenzophenone Drometrizole Octrizole Phenyl salicylate 2,4,4 -Trihydroxybenzophenone UV absorber, polymers 4-(2-Acryloyloxyethoxy)-2-hydroxybenzophenone polymer Benzophenone-1 Dipropylene glycol salicylate Drometrizole 2,4,4 -T ri hydroxybenzophenone UV absorber, polymethyl methacrylate 2,4,4 -Tri hydroxybenzophenone UV absorber, polyolefins Bumetrizole 2-(3, 5 -Di-t-butyl-2 -hydroxyphenyl)-5-chlorobenzotriazole 2-(2 -Hydroxy-3,5 -di-t-amylphenyl) benzotriazole Nickel bis [0-ethyl (3,5-di-t-butyl-4-hydroxybenzyl)] phosphonate Nickel diisobutyidithiocarbamate UV absorber, polyvinyl butyral Octrizole UV absorber, PP... 

In the same year, Iwasaki etol. [17] described the effect of a micro-reactor on the free radical polymerization of butyl acrylate, benzyl methacrylate, methyl methacrylate, vinyl benzoate, and styrene. In this case, the reactor system was a simple T-shaped mixing unit, followed by a polymerization section (the latter was responsible for an extended residence time). The total residence times were on the order of 0.5-10 min. In the T-shaped mixing section, the two liquids - one a neat monomer, the other toluene containing 0.03-0.05 mol 1 AIBN as initiator - were combined with the same flow rate. The decay of AIBN in the system was monitored initially at different temperatures, to verify that sufficient initiator was present for complete conversion under all reaction conditions. 

Figure 20-2. Dependence of the rate constant for polymerization termination by mutual deactivation of two polymer free radicals on the viscosity of the solvent for styrene (STY), methyl methacrylate (MMA), benzyl methacrylate (BMA) polymerizations at 2(fC. (After G. V. Schulz.)...

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