Acrylates Production

On the basis of available experimental data, it is impossible to choose a definite pathway of elimination of silanol. However, study of silylation of methyl P -nitropropionate (411) with BSA in the presence of trapping agents rigorously proved that silyl nitronate D is initially formed. This compound can be detected in the [3 + 2]-cycloaddition reaction with methyl acrylate product (413). If silylation of AN (411) is performed in the presence of ethyl vinyl ether, a-nitrosoalkene E can be successfully trapped in as heterodiene a Diels-Alder reaction. Dihydroox-azine (414) is formed, and its silylation affords isolable product (415). 

Some acrylates are still produced by a modified Reppe process that involves the reaction of acetylene, the appropriate alcohol (in the case of butyl acrylate, butyl alcohol is used), and carbon monoxide in the presence of an acid. The process is continuous and a small amount of acrylates is made this way. The most economical method of acrylate production is that of the direct oxidation of propylene to acrylic acid, followed by esterification. 

Close to 2 billion pounds of polymeric products based on acrylic and methacrylic esters are produced annually in the United States, about evenly divided between acrylates and methacrylates. A substantial fraction of the methacrylate products are copolymers. Most of the acrylate products are copolymers. The copolymers contain various combinations of acrylate and/or methacrylate monomers, including combinations of ester and acid monomers. Methyl methacrylate (MMA) is by far the most important methacrylate ester monomer, accounting for 90% of the volume of methacrylic ester monomers. Ethyl and n-butyl acrylates account for about 80% of the total volume of acrylate ester monomers. 

The most economical method of acrylate production is that of the direct oxidation of propylene to acrylic acid, followed by esterification. 

Extruded Plastic Sheet Rollstock Film Laminates Specialty Plastic Alloys Acrylic Products Color Concentrates Custom Packaging... 

C4C im][PF6] [C5C qm] [various] [C6py]Cl PdCl2 Pd(OAc)2 NaHC03 Et3N 40-200 °C. Phosphines and arsines as ligands arylation of acrylates product extracted with hexane. [58]... 

Celanese Acrylates, Product ManualA-70-1, Celanese Chemical Co., New York. 

Acrylics exhibit excellent adhesion to substrates such as concrete, masonry and wood. The majority of acrylic products are applied without using primer and give satisfactory adhesion. The more flexible resins give superior adhesion within the family of acrylic resins. The adhesive qualities of individual resins vary both with flexibility and with functionality. 

P, N] Some of the earliest examples of asymmetric Michael additions were reported by Yamada and co-workers, who used enamines derived from cyclohexanone and proline esters (19). The results of this study are summarized in Scheme 8 and Table 1. Although yields were generally poor, enantiomeric excesses as high as 59% were found using the tert-butyl ester of proline at low temperature (entry 5). Asymmetric induction was also observed with acrylonitrile, but no enantiomeric purities were reported. The enantiomeric purities of the methyl acrylate products were determined by measurement of optical rotations. 

There are also examples of gas-phase oxidation of allyl alcohol using Pd-Cu or Pd-Ag catalysts (Eq. (8.15)) [48]. The protocol was part of a multistep propylene-oxidation process, and the allyl alcohol starting material was produced from Pd-catalyzed acetoxylation of propylene followed by hydrolysis of allyl acetate (cf. Eqs. (8.2) and (8.3)) [48]. The presence of water improves the conversion of alcohol to acrylic products. 

FIGURE 12.53 U.S. production of synthetic fiber staple and tow showing the relative quantities of acrylic fiber produced compared to nylon, polyester, and polyolefin. Acrylic production peaked in the late 1970s. One of the major factors was the decline of the acrylic carpet market, now dominated by nylon. (From Manufactured Fiber Producer Handbook, 1996 Fiber Organon, February 1997, Fiber Economics Bureau, pub.)... 

When either method of preparation was carried out in the presence of methyl acrylate products derived from a 1 1 mixture oF the 1,2-and 1,4-isomers were obtained. On the other hand, in the presence of the more reactive dienophile methyl B-cyanoacrylate the products derived from the complex were again a mixture, but from the diaza--compound only adducts derived from 1,4-dideuteriocyclobutadiene were obtained. The intermediate cyclobutadiene cannot therefore have been square or again products apparently derived frbm the 1,2- or 1,4-isomers would have resulted since there would be no distinction between the isomers. It may also be deduced that both the decomposition of the diaza-compound and the trapping of the resultant cyclo-butadiene are concerted pericycllc processes and that a biradical intermediate cannot be involved. Apparently in the presence of the less reactive dienophile interconversion of the valence isomers is more rapid than the trapping cycloaddition reaction whereas with the more reactive dienophile the converse obtains. A lower limit of... 

Acrylates = (def) Different acrylic, styrene acrylic, vinyl acrylic products for applications ranging from cement additives to filters (e.g., acrylic acid esters, metallic salts of acrylic acid). 

One property of particular importance in construction that suffers when diene rubbers are used as impact modifiers is weatherability. Using acrylic rubbers and copolymers instead of dienes removes this problem. Some examples of acrylic products follow. 

However, most of the analysed acrylate products contained undeclared sensitising acrylics (meth)acrylates were not declared in 17 of 28 (61%) of the analysed products, and up to 46% of the materials present were undeclared, sensitising acrylics (Kanerva et al. 1997). 

As has been mentioned earlier, the focus of acrylic production has moved to Asia which now accounts for 46% of world capacity. The most recent information on world acrylic capacity is listed in Table 5 (92). China leads in bnilding new acrylic capacity with 16 plants as of 2000 and 19% of world capacity versus 8 plants and 9% of world capacity only 7 years earlier (93). Conversely, Europe, which had 38% of capacity in 1993 now has 29%. The changes in capacity and ownership of the major producers are shown graphically in Figure 15. 

Initial researches into acrylic polymers were concerned rather more with polyacrylates than polymethacrylates. The first acrylic polymer to be produced commercially was poly(methyl acrylate) production was begun in 1927 by Rohm and Haas AG in Germany. In about 1930, Hill of Imperial Chemical Industries Ltd. (U.K.) prepared cast poly(methyl methacrylate) and found it to be a potentially useful material but high raw material costs prohibited commercial development. (At this time, methyl methacrylate was obtained by dehydration of the hydroxyisobutyric ester.) In 1932 Crawford (also of Imperial... 

Most acrylic fibers are wet-spun, but dry spinning is also applied. The most common solvent is dimethylformamide, DMF. The polymerization of acrylics can also be carried out in DMF and the polymerization solution can then be directly spun. The boiling point of DMF is 153°C, making complete removal of solvent in the spinning column almost impossible. Most dry-spun acrylic production is staple fiber, and the remaining solvent is then removed during tow processing. 

Most acrylic production is for staple fiber. Huge spinning plates with up to 60 000 holes are used, and tow drawing and crimping are included in the process. Drawing takes place in a hot-water bath, which is possible because the wet glass transition temperature is about 75°C. The above-mentioned porosity of acrylics is used to control luster. Dried yams are very lustrous but can be made dull again by a hot wet treatment. 

Important properties of ethylene yclic olefin copolymers such as low melting point, high transparency, better optical characteristics, good heat stability, and high chemical resistance, have opened up its applications into areas like optoelectronic data transmission and data storage on a new generation of optical disks. These copolymers can effectively compete with existing acrylonitrile-butadiene-styrene polymers, polycarbonate and acrylics products. This will push polyolefins into the areas of speciality applications. 

Miniemulsion polymerization enables to incorporate water-insoluble materials such as resins, organic pigments, polymers, etc into the polymer matrix. The additive seed allows to control the particle number and particle size during the production process. Furthermore, miniemulsion polymerizations and copolymerizations carried out with acrylic and methacrylic monomers in the presence of unsaturated alkyd resins lead to the production of stable hybrid latex particles containing grafted and crosslinked alkyd resin/acrylic products as coating polymer [114]. In the reaction, the multifunctional resin acts as a hydrophobe as well as the costabilizer of the miniemulsion. 

Luran S acrylonitrile styrene acrylate product line, properties, processing, supplier design guide (B 566 e 1 10.83). BASF Aktiengesell-schaft 1983. 

Cast and extrusion sheet represents aroimd two-thirds of total acrylics production, the remainder being injection moulding applications. 

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