Polymerization of ethyl acrylate

Strohmeier and Hartmann [14] first reported in 1964 the photoinitiation of polymerization of ethyl acrylate by several transition metal carbonyls in the presence of CCI4. Vinyl chloride has also been polymerized in a similar manner [15,16] No detailed photoinitiation mechanisms were discussed, but it seems most likely that photoinitiation proceeds by the route shown in reaction Scheme (9). 

Items b and d may be related since the decrease in rate begins to be observed at about 40% conversion, i.e. at the point where [AN] has fallen to about 2.25 M. It is interesting to note that we ( ) and others ( 5) have also noted very slow rates of polymerization of ethyl acrylate at 1 M concentrations in ethyl acetate using either tetrabutyl ammoniurn bromide or 18-crown-6 as the phase transfer catalyst. Further studies in this area are needed. 

Fig. 31. Polymerization of ethyl acrylate by wool swelling at 25° C using water as a swelling agent (60% aquesous emulsion with 3.2% Triton X-405) (105)...

Polymerizations of acrylic and methacrylic esters are highly exothermic (e.g., A//polymeriZation of ethyl acrylate is 13.8 kcal/mol [2]). Generally, the heats of polymerization of acrylates are greater than those of methacrylates. 

Example C-tn-18 AE(50EO) for t ie emulsion polymerization of ethyl acrylate... 

In all such cases the process initiated by persulfate begins in the aqueous phase with the formation of water-soluble, surface-active polymeric radicals which, after growing to a certain critical size, precipitate to form particles subsequent polymerization proceeds mainly within these particles. The higher the solubility of the monomer in water, the more surface-active radicals and therefore primary particles are formed and the higher the stability and the concentration of the latex, A kinetic curve of the emulsifier-free polymerization of ethyl acrylate confirming this scheme is shown by Curve 1 in Fig. 3 (Yeliseyeva and Petrova, 1970). The process... 

Fig. 10, Variation of the number of partides during polymerization of ethyl acrylate in the presence of emulsifiers (i) sodium alkylsulfonate (2) oxyethylated (30) cclyl alcohol and (3) AAOES. Recipe m.p. ethyl acrylate, lOO emulsifier, AO ammonium persuUate. 0.5 water.

Fie, 21. Dependence of overall surface of particles ( ) on conversion during polymerization of ethyl acrylate. SDDS 1.04 xiO mcj/dm ammonium persulfate 0.44 X 10 moVdm phase ratio, 1 9 i 45°C. 

Macroradicals were obtained by the polymerization of ethyl acrylate in cyclohexane, styrene in hexane, vinyl acetate in decane, and methyl methacrylate in hexane. Because of the solubility of the vinyl acetate block in hexane, the ratio of the weight of vinyl acetate to that of the macroradical in poly (methyl methacrylate-b-vinyl acetate) after heating at 50°C for three days was only 30/100. By contrast, because of the insolubility of the acrylonitrile block in hexane, good yields of methyl methacrylate-b-acrylonitrile macroradicals were obtained. The ratio of the weight of the acrylonitrile block to that of the macroradical was thus 90/100 after heating the mixture for three days at 50°C in hexane. 

Similar techniques have been used to incorporate silica into various polymers. (Mineral fillers are often given hydrophobic coatings to help in their dispersion in polymers such as polyolefins.60) Methacrylatopropyltrimethoxysi-lane has been used to add the methacrylate group on to silica. The treated silica was used in the emulsion polymerization of ethyl acrylate.61 Transparent films could be formed from the product. Living polystyrene was end-capped with a triethoxysilane (5.20), after which it was used to treat silica and alumina.62... 

In comparing free-radical polymerizations of ethyl acrylates in benzene and in dimethyl formamide at 50 the rates were found to be proportional to the square roots of the initiator concentration. They were not proportional, however, to the concentrations of the monomer. This was interpreted in terms of hot radicals. ... 

The method of the multifunctional initiator was used for the synthesis of 3- and 4-arm stars. Trimethylolpropane triacrylate was converted to a silyl enol ether capable of initiating the polymerization of ethyl acrylate to form the corresponding 3-arm star " (Scheme 50). 

H. Datta, N.K. Singha, A.K. Bhowmick, Beneficial effect of nanoclay in atom transfer radical polymerization of ethyl acrylate a one pot preparation of tailor-made polymer nanocomposite. Macromolecules 41 (1) (2008) 50-57. 

Figure 10.6 Schematic representation for the attachment of ATRP initiator onto clay surface via esterification and the subsequent polymerization of ethyl acrylate by using surface-initiated ATRP (reproduced with permission from J Polym Sci Part A Polym Chem 2008, 46, 5014).

Table 1. Polymerization of Ethyl acrylate (EA) with various Comonomers Allyl glycidyl ether (AGE), Glycidyl methacrylate (GMA) and Methacrylic acid (MAA)...

A condensation polymerization run Simulataneously with an addition polymerization plus appropriate crosslinking can produce a SIN. Specifically, we employed an epoxy formulation with ethyl acrylate. When a tertiary amine is used to cure the epoxy, there apparently is minimal interference with the simultaneous polymerization of ethyl acrylate. 

Solution Copolymerization of Glycidyl Methacrylate and Styrene 41-8. Redox Emulsion Polymerization of Ethyl Acrylates 41-9. Preparation of Isotactic Poly(methyl methacrylate)... 

The control of the properties of polymers obtained by emulsion polymerization of ethyl acrylate by incorporating small amounts of functional groups or varying the conditions of polymerization is reported by Eliseeva [48] in 1979. 

Two examples of the core-first approach for the synthesis of star polymers by GTP have been reported. Trimethylolpropane triacrylate is converted to a silyl enol ether that is used to initiate the polymerization of ethyl acrylate (Scheme 6). A pol)aner with a = 2190 and MJM = 1.39 was obtained [9]. A cyclic tetramer of methyl hydrogen siloxane was converted to a core containing four initiating groups using a Pt-catalyzed hydrosilylation reaction. The tetrafiinctional initiator was used to initiate the polymerization of MMA to form a four-arm star PMMA (Scheme 7), with about 20 to 150 MMA repeat... 

The continuous bulk polymerization of methyl methacrylate was used as an example in Section 5.2. A stirred bulk polymerization like that used for styrene (Section 5.4) could be adapted for methyl methacrylate. A suspension process for poly(methyl methacrylate) was described in Section 5.4. The polymerization of ethyl acrylate most often is carried out in emulsion. A process such as that used for vinyl acetate is suitable (Section 16.4). Like vinyl acetate, the monomer is slightly water soluble, so true emulsion polymerization kinetics are not followed. That is, there is initiation of monomer dissolved in water in addition to that dissolved in growing polymer particles. Ethyl acrylate is distinguished by its rapid rate of propagation. Initiation of a 20% monomer emulsion at room temperature by the redox couple persulfate-metabisulflte can result in over 95% conversion in less than a minute. As with vinyl acetate polymerization, a continuous addition of monomer at a rate commensurate with the heat transfer capacity of the reactor is necessary in order to control the temperature. 

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