Methyl methacrylate, copolymers with poly

Commercial impact-modified acrylic resins (Table 19.15) exhibit five- to tenfold improvement in the notched Izod impact strength and the ultimate tensile elongation compared to the neat PMMA resin. These impact-modified acrylics are usually blended captively by the manufacturers of the acrylic resins. The base resin in a typical weatherable grade (Plexiglas DR, Rohm and Haas) could be a methyl methacrylate copolymer with ethylacrylate and styrene, while the rubber additive (ca. 10 %) could be an emulsion-polymerized, PMMA-grafted, cross-linked poly (n-butylacrylate) rubber of controlled particle size (<200 nm). The nonweatherable impact-modified acrylic (XT, CYRO) typically consists of a MMA/S/AN copolymer with MBS (ca. 10 %) rubber particle dispersions. 

It has been demonstrated that this principle may be used to characterize polymer compatibility (18). A typical example of the data obtained is shown in Figure 1 for blends of anthracene-labeled poly(methyl methacrylate) (PMMA) and naphthalene-labeled methyl methacrylate copolymers with ethyl or butyl methacrylate. When both the donor and the acceptor... 

Preparation of Block Copolymers. Poly(styrene-b-methyl methacrylate) and poly(styrene-b-t-butyl methacrylate) were prepared by procedures similar to those reported for poly(styrene-b-methyl methacrylate (12,13). Poly(methyl methacrylate-b-t-butyl methacrylate) was synthesized by adaptation of the method published (14) for syndiotactic poly(methyl methacrylate) polymerization of methyl methacrylate was initiated with fluorenyllithium, and prior to termination, t-butyl methacrylate was added to give the block copolymer. Pertinent analytical data are as follows. 

Figure 3. Time dependence of the fraction R of unreacted aminostyrene residues during acetylation by 0.14 M acetic anhydride at 30°C. Methyl methacrylate copolymer in acetonitrile solution (0) linear poly-(methyl methacrylate-co-butyl methacrylate) swollen with acetonitrile Cd) methyl methacrylate copolymer crosslinked with 1 mole% ( ) and with 15 mole% ( ) ethylene dimethacrylate poly(methacrylate crosslinked with 3 mole% ethylene dimethacrylate containing entrapped poly(methyl acrylate-co-aminostyrene) ( ).

Figure 41. A plot of sensitivity to Mo (5.4k) x-ray radiation and 20 kV electron beam radiation for several resists. EPB is epoxidized polybutadiene, P(GMA-EA) is a copolymer of glycidyl methacrylate and ethyl acrylate (COP), PGMA is poly (glycidyl methacrylate), PBS is poly (butene-1 -sulfone), FBM-1 is poly (2,2,3,3-tetrafluoropropyl methacrylate), P(MMA-MA) is a copolymer of methyl methacrylate and methacrylic acid, PMMA is poly (methyl methacrylate). (Reproduced with permission from Ref. 56J...

Core-shell emulsion polymers with a core or rubbery stage based on homopolymers or copolymers of butadiene are used as impact modifiers in matrix polymers, such as ABS, for styrene acrylonitrile copolymer methyl methacrylate (MMA) polymers, poly(vinyl chloride) (PVC), and in various engineering resins such as polycarbonate) (PC) poly(ester)s, or poly(styrene)s, further in thermosetting resins such as epoxies. 

M. Fowler, J. Barlow, and D. Paul, Effect of copolymer composition on the miscibility of blends of styrene-acrylonitrile copolymers with poly (methyl methacrylate), Polymer, 28(7) 1177-1184, June 1987. 

Outdoor aging is currently being conducted on these polymers, and while accelerated aging may have limited value in predicting long term outdoor exposure, the accelerated aging studies of Jordan et al. (9) with poly (methyl methacrylate) copolymers and homopolymers indicated that a 2000-hour carbon-arc weatherometer period was a realistic exposure to screen the relative changes to be expected in about a two-year period in an outdoor environment—e.g., Florida or Arizona. 

Figure 5. GPC curves of 1, cellulose nitrate 2, polyf methyl methacrylate) 3, physical mixture of cellulose nitrate and polyf methyl methacrylate) and 4, graft copolymer of cellulose nitrate-g-poly-(methyl methacrylate). (Reprinted, with permission, from Ref. 21. 

The reactions are just like the ones that produce polystyrene. First, a molecule of methyl methacrylate reacts with a polystyryl anion to form a methyl methacrylate anion (crossover). Then the methyl methacrylate block grows in a series of propagation steps, followed by the addition of methanol to effect termination as before. We can draw the structure for the block copolymer, named poly styrene-6/oe -methyl methacrylate) as is shown here. 

The H and 13C NMR spectra of azo compounds incorporated into monomers and polymers have been measured.67-73 Chiral methacrylic polymers containing azobenzene chromophore,67,68 epoxy-based polymers functionalized with tricyanivinylphenylazo chromophores,69 4-vinylazobenzene and homo- and copolymers,70 microstructure of trans-4-acrylooyloxyazo-benzene/methyl methacrylate copolymers,71 optically active poly[(S)-4-(2-methacryloyloxypropanoyloxy)azobenzene]72 and polyetherurethane pendant with azo dye by TV-substitution73 have been studied. 

Physical Properties of Blends of Polystyrene with Poly(methyl Methacrylate) and Styrene/ (methyl Methacrylate) Copolymers... 

Figure 1. Room-temperature miscibility diagrams for blends of polystyrene with poly(methyl methacrylate) and styrene/(methyl methacrylate) copolymers. Shaded area is compatible region.

In a related patent (46) Amagi et al. synthesized a triple latex IPN. In brief, polymer 1 was a crosslinked SBR, polymer 2 was a crosslinked styrene-methyl methacrylate copolymer, and polymer 3 was a crosslinked poly (methyl methacrylate). All three were sequentially synthesized on the same latex particle. The latex material was then mechanically blended with linear poly (vinyl chloride). Also, Torvik (47) blended together four polymers that had different glass transition temperatures. 

Effects of additives in the matrix were observed by substituting for methyl methacrylate a poly (methyl methacrylate) homopolymer with a solution molecular weight of 950,000, a vinylidene fluoride copolymer (Pennwalt s Kynar 7201), and a methacrylate-butadiene-styrene impact modifier (Marbon s Blendex BTA IIIN). Concentrations were 2% on the total dispersion volume. The same additives were studied at the same volume concentration in the dispersed phase. Barium sulfate (Whittaker, Clark, and Daniels Barytes No. 91), a commonly used additive for radiopacity, was also studied in the dispersed phase. Responses were observed by the test methods described below. 

FIG. 7 Positive ion ToF-SIMS spectra of methyl methaerylate-poly(ethylene glycol) methacrylate copolymers with average PEG molecular weights of I(XX). (From Ref. 33.)... 

The wetting results in this study also agree with those found by Gregonis, et al. (11). who studied the wetting by water of films of copolymers of poly(hydroxyethyl) methacrylate(HEMA) with poly(methyl methacrylate)(MMA). The hydroxy group would impart a hydrophilicity to these copolymers analogous to that of the carboxyl group in the AA/BMA copolymer in the present study. 

Elsewhere [182], the morphology of polystyrene/poly(methyl methacrylate) blends with methyl methacrylate/POSS random copolymers (containing 5.5% m/m—PMMA-POSS5 8.0% m/m - PMMA-POSSIO and 10.7% m/m—... 

One of the cases of such complementarity may be the atactic polymer which can be considered as a copolymer of isotactic and syndiotactic links. Indeed, the composition and properties of the polyccanplex depend on the chain stereoregularity, for example in the case of poly(methyl methacrylate) stereocomplexes and poly(ethylene glycol) with isotactic or atactic PAA complexes ... 

Roylance et al. studied yielding at temperatures between 0 and 75 °C in AMBS polymers, which are poly (styrene-acrylonitrile-methyl methacrylate) copolymers containing polybutadiene particles, and showed that Eq. (5) is obeyed over three decades of strain rate ). Nominal mbber contents varied between 0 and 13%, and the slopes of the Eyring curves changed with rubber content in the direction predicted by Eq. (8). As mbber phase volumes are not given, the data cannot be... 

A combination of liquid adsorption chromatography with SEC has recently been developed by several workers. Poly(styrene-methyl methacrylate) copolymers were fractionated according to chemical composition by liquid adsorption chromatography and the molecular weight averages of each fraction were measured by SEC [5,6]. 

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