Poly acrylic esters

Monomer Synthesis. Methyl acrylate is commercially produced by routes similar to those used for acrylic acid. 

In the process using acetylene, water is replaced by methanol, and HCl is added  

The reaction is carried out at 170-180°C and 30 bar with nickel compounds as catalysts, for example, (NiBr2[(C6H5)3P]2 C4H9Br. 

In the ethylene method, water is again replaced by methanol, and the resulting ammonium bisulfate melt is drawn off from the base of the column. 

In the ketene method, j8-propiolactone is heated with methanol and alkyl sulfate (or dialkyl sulfate) to 100-200°C to eliminate water, thereby yielding methyl acrylate. 

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The lanthanocene initiators also polymerize EtMA, PrMA and BuMA in a well-controlled manner, although syndiotacticity decreases as the bulk of alkyl substituent increases. Reactivity also decreases in the order MMA EtMA > PrMA > BuMA. Chain transfer to provide shorter polymer chains is accomplished by addition of ketones and thiols.460 The alkyl complexes (190) and (191) also rapidly polymerize acrylate monomers at 0°C.461,462 Both initiators deliver monodisperse poly(acrylic esters) (Mw/Mn 1.07). An enolate is again believed to be the active propagating species since the model complex (195) was also shown to initiate the polymerization of MA. 

Poly(acrylic esters) such as poly(methyl methacrylate)... 

Poly(acrylic ester) based flow modifier (25) ... 

The most widely investigated optically active poly-acrylic-esters are the polymers of bomyl and menthyl acrylate and methacrylate in this case the monomers have been polymerized by radical polymerization using benzoyl-peroxide (135), A. I. B. N. (134, 135), y-rays (131, 135), U. V. rays (4) in the presence of benzoin (134), and by anionic polymerization using LiC4H9 (4, 135) or C6H5MgBr (134, 135) as catalyst. 

Attempts to predict miscibility using simple solubility parameters of the type described in Chapter 1 have been largely unsuccessful because strong dipolar interactions are not taken into account. The importance of these interactions has been demonstrated, for example, with miscible mixtures of poly(acrylic esters) and poly(vinyl fluoride), where the compatibility has been attributed to dipolar interactions of the type... 

ABR Poly(acrylic ester-co-butadiene) (elastomer ASTM lUPAC) see also AR... 

Orientations in elongated mbbers are sometimes regular to the extent that there is local crystallization of individual chain segments (e.g., in natural rubber). X-ray diffraction patterns of such samples are very similar to those obtained from stretched fibers. The following synthetic polymers are of technical relevance as mbbers poly(acrylic ester)s, polybutadienes, polyisoprenes, polychloroprenes, butadiene/styrene copolymers, styrene/butadiene/styrene tri-block-copolymers (also hydrogenated), butadiene/acrylonitrile copolymers (also hydrogenated), ethylene/propylene co- and terpolymers (with non-conjugated dienes (e.g., ethylidene norbomene)), ethylene/vinyl acetate copolymers, ethyl-ene/methacrylic acid copolymers (ionomers), polyisobutylene (and copolymers with isoprene), chlorinated polyethylenes, chlorosulfonated polyethylenes, polyurethanes, silicones, poly(fluoro alkylene)s, poly(alkylene sulfide)s. 

Figure 10-19. Brittleness temperature of poly(acrylic esters) (PAES) and poly(methacrylic esters) (PMES) as a function of the number N of carbon atoms in the aliphatic side chains.

Hosokawa, Y. Kuroki, M. Aida, T. Inoue, S. Controlled synthesis of poly(acrylic esters) by aluminum porphyrin initiators. Macromolecules 1991, 24, 824-829. 

Poly-acrylic ester compounds O ring compounds (Table 10.14)... 

Graft copolymer of A -vinylpyrrolidone with such polymers as dextran, poly(acrylate esters), polyacrylonitrile, polytetrafluoroethylene, poly(methyl methacrylate) films, polyester films, and polyolefins have been reported [24]. 

To study the properties of isotactic poly(acrylic acid), it is necessary to prepare an isotactic poly(acrylate ester) first. The common practice is to polymerize isopropyl acrylate in the presence of /z-butyllithium or of phenylmagnesium bromide at -78 "C in toluene [19]. The polymer is then hydrolyzed as completely as possible so as not to disturb the regularity of the conformation, hinder the cryallization of the polymer (if it is capable of crystallizing), alter its solubility, or change the shape of the polymer chains in solution. 

By using this approach, Zambelli and coworkers [28], have shown that cis-enchainment occurs during Ziegler-Natta catalyzed polymerizations of propylene. Similar studies on isotactic poly(acrylic esters) [1,29-33] isotactic poly(ethyl cis-di-methacrylate) [34], predominantly isotactic poly(vinyl ethers) [2,7,21,35,36] and poly(propylene sulfide) [22] have been reported. 

Poly(acrylate esters), often called acrylics, have grown from their first introduction in the mid-1950s to account for about one-quarter of the domestic PSA market. The pioneering research in this field by Ulrich revealed that the normally tacky polymers of certain acrylic esters could be converted to useful adhesives by the incorporation of up to about 10% of a polar monomer. The acrylate esters of C4-C12 alcohols, giving homopolymers having a Tg of about -50°C to about —75°C, are the major constituent of the PSA. 

Poly(acrylate ester)s Polyacrylamide Lignosulfonates Poly(sulfonic acid)s Poly(vinyl chloride)... 

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