Copolymerization methyl methacrylate

AH-acryHc (100%) latex emulsions are commonly recognized as the most durable paints for exterior use. Exterior grades are usuaHy copolymers of methyl methacrylate with butyl acrylate or 2-ethyIhexyl acrylate (see Acrylic ester polymers). Interior grades are based on methyl methacrylate copolymerized with butyl acrylate or ethyl acrylate. AcryHc latex emulsions are not commonly used in interior flat paints because these paints typicaHy do not require the kind of performance characteristics that acryHcs offer. However, for interior semigloss or gloss paints, aH-acryHc polymers and acryHc copolymers are used almost exclusively due to their exceUent gloss potential, adhesion characteristics, as weU as block and print resistance. 

By means of the spatially intermittent reactor, Ito and O Driscoll determined, for example, the absolute rate constant of termination, fct, for methyl methacrylate copolymerization with butyl or dodecyl methacrylate. The value of /ct is a function of the monomer mixture composition [89]. 

Figure 10.8. Instantaneous copolymer composition in cationic, free-radical, and anionic styrene/methyl methacrylate copolymerization initiated by SnCl4, benzoyl peroxide, and Na in liquid NH3, respectively (from Pepper [128]).

In the end of 1960s, Nikolaev et al.29 and Ito et al.30 independently demonstrated an appreciable effect of the reaction medium on the reactivity ratios in the copolymerization of methyl methacrylate and styrene (Table 19). Ito et al. found that the relative reactivity of methyl methacrylate toward the polystyryl radical is correlated with the transition energies ET for the longest wavelength absorption band for pyridinum TV-phenolbetaine in solvents. They suggested that the polarized structure of methyl methacrylate monomer becomes important in the transition state. Bonta et al.32 also demonstrated that there is an appreciable solvent effect on the reactivity ratio in the styrene-methyl methacrylate copolymerization in non-... 

MA Diels-Alder adducts, 118, 119, 158, 159 MA ene reaction, 119, 158, 159 MA equimolar copolymerization, 270, 273 MA-metal complex polymerization, 212 maleate and fumarate copolymerization, 365, 369 maleimide copolymerization, 266, 365 MA nonequimolar copolymerization, 270-298 MA reactivity ratios, 302 methyl methacrylate copolymerization with MA CTC, 370... 

Terephthaldoxime, //,// -[4,4-diphenyl(methane)] bismaleimide reaction, 514 Terephthalic acid, polyesters use, 494 Termination rate constant, MA-methyl methacrylate copolymerization, 281 Terpenes... 

Various methacrylate esters have been disclosed as modifiers of DADC. Thus methyl methacrylate polymer may be dissolved in DADC and the sheets cast (22). When DADC is copolymerized with methyl methacrylate, a silane derivative may be added to control the release from the mold (23). 

The DADC monomer has been copolymerized with small amounts of polyfunctional methacryflc or acryflc monomers. For example, 3% triethylene glycol dimethacrylate was used as a flexibiflzing, cross-linking agent with a percarbonate as initiator (26). CR-39 and diethylene glycol diacrylate containing isopropyl percarbonate were irradiated with a mercury lamp to a 92% conversion and then cured at 150°C (27). By a similar two-step process DADC was copolymerized with methyl methacrylate and tetraethylene glycol dimethacrylate (28). 

Fig. 2. Relationship between relative rate and monomer composition in the copolymerization of DAP with vinyl monomers A, styrene or methyl methacrylate B, methyl acrylate or acrylonitrile C, vinyl chloride D, vinyl acetate, and E, ethylene (41).

Polymerization and Spinning Solvent. Dimethyl sulfoxide is used as a solvent for the polymerization of acrylonitrile and other vinyl monomers, eg, methyl methacrylate and styrene (82,83). The low incidence of transfer from the growing chain to DMSO leads to high molecular weights. Copolymerization reactions of acrylonitrile with other vinyl monomers are also mn in DMSO. Monomer mixtures of acrylonitrile, styrene, vinyUdene chloride, methallylsulfonic acid, styrenesulfonic acid, etc, are polymerized in DMSO—water (84). In some cases, the fibers are spun from the reaction solutions into DMSO—water baths. 

O.JVI. Scott Sons. The O.M. Scott Sons Co. (Scotts) has developed a series of coated products which utilize copolymer blends of vinyHdene chloride copolymerized with methyl methacrylates, acrylonitriles, methyl acrylates, and/or vinyHdene—vinyl chloride monomers. 

Pure polymeric acrylonitrile is not an interesting fiber and it is virtually undyeable. In order to make fibers of commercial iaterest acrylonitrile is copolymerized with other monomers such as methacrylic acid, methyl methacrylate, vinyl compounds, etc, to improve mechanical, stmctural, and dyeing properties. Eibers based on at least 85% of acrylonitrile monomer are termed acryHc fibers those containing between 35—85% acrylonitrile monomer, modacryhc fibers. The two types are in general dyed the same, although the type and number of dye sites generated by the fiber manufacturing process have an influence (see Eibers, acrylic). 

Styrene monomer was also copolymerized with a series of functional monomers by using a single-step dispersion copolymerization procedure carried out in ethanol as the dispersion medium by using azobisizobu-tyronitrile and polyvinylpyrollidone as the initiator and the stabilizer, respectively [84]. The comonomers were methyl methacrylate, hydroxyethyl acrylate, metha-crylic acid, acrylamide, allyltrietoxyl silane, vinyl poly-dimethylsiloxane, vinylsilacrown, and dimethylamino-... 

In contrast to /3-PCPY, ICPY did not initiate copolymerization of MMA with styrene [39] and AN with styrene [40]. However, it accelerated radical polymerization by increasing the rate of initiation in the former case and decreasing the rate of termination in the latter case. The studies on photocopolymerization of MMA with styrene in the presence of ICPY has also been reported [41], /8-PCPY also initiated radical copolymerization of 4-vinylpyridine with methyl methacrylate [42]. However, the ylide retarded the polymerization of N-vinylpyrrolidone, initiated by AIBN at 60°C in benzene [44]. (See also Table 2.)... 

Kondo maintained his interest in this area, and with his collaborators [62] he recently made detailed investigations on the polymerization and preparation of methyl-4-vinylphenyl-sulfonium bis-(methoxycarbonyl) meth-ylide (Scheme 27) as a new kind of stable vinyl monomer containing the sulfonium ylide structure. It was prepared by heating a solution of 4-methylthiostyrene, dimethyl-diazomalonate, and /-butyl catechol in chlorobenzene at 90°C for 10 h in the presence of anhydride cupric sulfate, and Scheme 27 was polymerized by using a, a -azobisi-sobutyronitrile (AIBN) as the initiator and dimethylsulf-oxide as the solvent at 60°C. The structure of the polymer was confirmed by IR and NMR spectra and elemental analysis. In addition, this monomeric ylide was copolymerized with vinyl monomers such as methyl methacrylate (MMA) and styrene. 

An effective method of NVF chemical modification is graft copolymerization [34,35]. This reaction is initiated by free radicals of the cellulose molecule. The cellulose is treated with an aqueous solution with selected ions and is exposed to a high-energy radiation. Then, the cellulose molecule cracks and radicals are formed. Afterwards, the radical sites of the cellulose are treated with a suitable solution (compatible with the polymer matrix), for example vinyl monomer [35] acrylonitrile [34], methyl methacrylate [47], polystyrene [41]. The resulting copolymer possesses properties characteristic of both fibrous cellulose and grafted polymer. 

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