METHACRYLIC ESTER POLYMER

The nature of the alkyl group from the esterifying alcohol, the molecular weight, and the tacticity determine the physical and chemical properties of methacrylate ester polymers. 

In methacrylic ester polymers, the glass-transition temperature, is influenced primarily by the nature of the alcohol group as can be seen in Table 1. Below the the polymers are hard, brittle, and glass-like above the they are relatively soft, flexible, and mbbery. At even higher temperatures, depending on molecular weight, they flow and are tacky. Table 1 also contains typical values for the density, solubiHty parameter, and refractive index for various methacrylic homopolymers. 

Figure 15.12. Brittle points of n-alkyl acryl acrylate and methacrylate ester polymers. (After Rehberg and Fisher, copyright 1948 by The American Chemical Society and reprinted by permission of the...

B.B. Kine and R.W. Novak, Acrylic and methacrylic ester polymers. In J.I. Kroschwitz (Ed.), Encyclopedia of Polymer Science and Engineering, Wiley, Chichester, 1985, pp. 234-299. 

Dispersion devices, ozone, 17 801-802 Dispersion force, 12 4 Dispersion-free solvent extraction, 10 766 Dispersion hardening, 13 501, 502, 527 of refractory metal alloys, 13 528 Dispersion polymerization, 24 156-157 of acrylamide polymers, 1 323 of methacrylic ester polymers, 16 289 Dispersion processing of FEP polymer, 18 314... 

Grafting from method, 7 652-653 Grafting onto method, 7 654 Grafting process, 73 537 Grafting through method, 7 653 Graft polymerization. See also Graft copolymerization ABS, 7 419, 421 acrylic ester monomers, 7 386 of methacrylic ester polymers, 76 289-290... 

Living organisms, fermentation by, 11 1-2 Living polymerization, 23 728 of acrylic ester monomers, 1 386 of methacrylic ester polymers, 16 291 Living polymers, 24 705 Living ring-opening metathesis... 

See a/so Methacrylic ester monomers Methacrylic ester polymers Methacrylic monomers acute toxicity of, 16 260t exposure to, 16 261 for 193-nm resists, 15 178-179 physical properties of, 16 227-235t, 278t polymerization of, 14 259 Methacrylates... 

Methacrylates Methacrylic ester polymers copolymerization with acrylic monomers, l 380t... 

See also Methacrylate monomers polymerization data for, 16 279t Methacrylic ester polymers, 16 271-298. See also Methacrylate monomers Methacrylic esters analytical test methods and specifications for, 16 291-293 bulk polymerization of, 16 281-282 chemical properties of, 16 276-277 electrical properties of, 16 276 emulsion polymerization of, 16 285-288 glass transition temperature of, 16 273-274... 

Nonaqueous dispersion (NAD) polymerization, 20 82 of methacrylic ester polymers, 16 289 Nonaqueous media, separations in, 21 654r-656... 

Radical grafting, 10 206 Radical-induced decompositions, 14 280 of dialkyl peroxydicarbonates, 14 289 Radical ozone reactions, 17 774 Radical polymerization, 22 40. See also Free-radical polymerization controlling, 14 297 of methacrylic ester polymers, 16 279-290... 

Sheet production, of methacrylic ester polymers, 16 282 Sheet silicon, 23 40—41 Shell a-olefin manufacture, 17 713—714. See also Shell higher olefins process (SHOP)... 

Use Organic synthesis, particularly of adipic acid and caprolactam (about 95%), polyvinyl chloride and its copolymers, and methacrylate ester polymers wood stains paint and varnish removers, spot removers degreasing of metals polishes leveling agent dyeing and delustering silk lubricating oil additive solvent for cellulosics natural and synthetic resins, waxes, fats, etc. 

Among methacrylic ester polymers, poly(methyl methacrylate) is the most important one industrially. Most of it is prepared by free-radical polymerizations of the monomer and a great deal of these polymerizations are carried out in bulk. Typical methods of preparation of clear sheets and rods consist of initial partial polymerizations in reaction kettles at about 90°C with peroxide initiators. This is done by heating and stirring for about 10 min to form syrups. The products are cooled to room... 

Methyl Methacrylate. The most generally usefiil initiator for anionic polymerization of MMA and related compounds is 1,1-diphenylhexyllithium which is formed by the quantitative and facile addition of butyllithium with 1,1-diphenylethylene (DPE) (eq. 17) (46). Using this initiator in THF at -78°C, it is possible to polymerize MMA to obtain polymers and block copolymers with predictable molecular weights and narrow molecular weight distributions. Controlled polymerizations are not effected in nonpolar solvents such as toluene, even at low temperatures. Other usefiil initiators for polymerization of MMA are oligomers of (a-methylstyryl)lithium whose steric requirements minimize attack at the ester carbonyl group in the monomer. These initiators are also useful for the polymerization of 2-vinylpyridine (see Methacrylic Ester POLYMERS). 

See Ethylene Polymers, LDPE Ethylene Polymers, HDPE Ethylene Polymers, LED PE Vinyl Alcohol Polymers Vinyl Chloride Polymers Vinylidene Chloride Polymers (PVDC) Polyamides, plastics Polyesters, thermoplastic Propylene Polymers (PP) Methacrylic Ester Polymers Acrylonitrile Polymers Styrene Polymers (PS) Ionomers. 

See Acrylic Ester Polymers, Methacrylic Ester Polymers. f See Poly(arylene sufide)s. 

More About Engineering Thermoplastics. Many of the individual resins mentioned in this overview are covered in articles devoted to them. Cross references are provided in Table 1. A list of related articles is as follows Acetal Resins Acrylic Ester Polymers Acrylonitrile and Acrylonitrile Polymers (SAN and ABS) Ethylene-Norbornene Copolymers Liquid Crystalline Polymers, Main-Chain Methacrylic Ester Polymers ... 

METHACRYLIC ESTER POLYMERS. See Volume 3. MICROCELLULAR PLASTICS. See Volume 7. MICROEMULSION POLYMERIZATION. See Volume 7. MICROGELS. See Smart Materials, Microgels. MICROMECHANICAL PROPERTIES. See Volume 3. MISCIBILITY. See Volume 7. 

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