Methyl methacrylate units

The formation of methacrylic acid units was clearly observed in the difference spectrum for the copolymer containing 74.7 mol% of methyl methacrylate units as shown in Figure 8. By comparing this spectrum with the... 

Figure 8. Difference infrared spectra between the polymers unexposed and exposed to electron-beam of 1 x 10 4 C/cm2. (A) Poly(a,a-diphenylethyl methacrylate-co-methyl methacrylate) containing 74.7 mol% of methyl methacrylate units (B) Poly (methyl methacrylate).

The homopolymer of triphenylmethyl methacrylate is not soluble in usual organic solvents but it is solubilized by the incorporation of methyl methacrylate units. The copolymers containing over 90 mol% methyl methacrylate are soluble in the organic solvents such as toluene and xylene. In... 

When two different polymers are condensed with a diol, block copolymers are obtained. The synthesis of such a copolymer was reported, in which a block of 100 styrene units was located between two blocks of about 120 methyl methacrylate units. 

Table 6.1 Copolymer composition Xa versus monomer feed composition xf in homogeneous copolymerization of styrene Mt and methyl methacrylate M2 T = 60 °C at low conversions (less than 10%) determined by means of NMR and elementary carbon analysis. (Abbreviations NMR1 and NMR2 correspond to spectra with resonating proton located in styrene and methyl methacrylate unit, respectively)... 

Table 6.5 Experimental dependences of fractions of triads centered by methyl methacrylate unit and MMA characteristic coefficient (6.15) on monomer feed composition for bulk copolymerization of styrene with methyl methacrylate at T = 60 °C [80]...

A detailed long-term study of the photochemical behaviour of 95 (R = H) revealed that after several thousands of hours of accelerated ageing, surface deterioration becomes noticeable [342]. This deterioration was due to some photochemical oxidation of the methyl methacrylate units. The benzotriazole chromophore moiety remained unchanged. 

Thermal volatilization analysis (TVA) of blends or mixtures of PP and poly(methyl methacrylate) (PMMA) reveals that the PMMA component tends to be stabilized and the PP destabilized. Pre-Irradlatlon of blends strongly suppresses the yield of monomeric methyl methacrylate but methyl methacrylate units appear In the chain fragment fraction. 

The isotacticity is higher in poly[(R)-Q-methylbenzyl methacrylate] prepared by BuLi in toluene than in the polymer of the racemic monomer. However, the stereoregularity of poly[(S)-a-methylbenzyl methacrylate-co-methyl methacrylate] is mostly the same as that of poly((RS)-a-methylbenzyl methacrylate-co-methyl methacrylate], regardless of their compositions except for low methyl methacrylate contents. This indicates that the isotactic placement of the (R)- or (S)-monomer to the growing chain ending in the antipode monomer unit is less favorable than to die anion of the same monomer unit, while the stereospecificity in the addition of a-methylbenzyl methacrylate to methyl methacrylate unit should be the same between the (R)- and (S)-monomers. ... 

Add 5 X 0.3 for the five 8-carbons two in the backbone, two a-methyls in adjacent methyl methacrylate units, and one methoxy in the pendant group. The estimated shift is now 24.1 ppm. 

A spherical self-assembled complex bearing 24 methyl methacrylate units in its interior was prepared by Fujita et al. It was demonstrated that endohedral radical polymerization can be promoted dne to the increased concentration of monomer units at the core of the complex [71]. 

Figure 8.16 The product Q hu Q) for a monolayer of syndiotactic poly(methyl methacrylate) spread on water hu Q) is the partial structure factor for the methyl methacrylate units. The solid line is a fit to the data for a uniform layer of thickness 23 A.

Raymond, P.C., Koros, W.J., and Paul, D. R. (1993) Comparison of mixed and pure gas permeation characteristics for CO2 and CH4 in copolymers and blends containing methyl methacrylate units. 

The triplet lifetime and the quantum yield of the chain scission ( J of copolymers of phenyl isopropenyl ketone and methyl methacrylate are independent of copolymer composition, indicating that the photolysis of the phenyl isopropenyl ketone moieties is not influenced by neighbouring methyl methacrylate units. 

Comparison of the physical blend, Nafion-H/PMMA, with the ph mically combined copolymers. The degradation of Nafion-H/PMMA blends and 2-SEM/MMA copolymers both show significant char formation, indicating that the methyl methacrylate units of both interact with the sulfonic acid groups. As illustrated in the Schemes, the process by which this occurs is different but the end result is that MMA is incorporated into the char rather than simply producing monomer as is seen in PMMA degradation. 

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