Butyl acrylate homopolymerization

NMP is as successful as RAFT polymerization for the construction of block copolymers. A small library of block copolymers comprised of poly(styrene) (PSt) and poly(ferf-butyl acrylate) (FYBA) was designed and the schematic representation of the reaction is depicted in Scheme 10 [49]. Prior to the block copolymerization, the optimization reactions for the homopolymerization of St and f-BA were performed as discussed in this chapter (e.g., see Sect. 2.1.2). Based on these results,... 

Maleate Surfmers were found to outperform methacrylic and crotonic compounds in the copolymerization of styrene, butyl acrylate and acrylic acid in seeded and nonseeded semicontinuous processes [17]. The maleate Surfmer achieved high conversion without homopolymerization in the aqueous phase which can result in emulsion instability. The methacrylate Surfmer was too reactive as opposed to the crotonate which was not sufficiently reactive. The reported dependence of the maleate Surfmer conversion on the particle diameter is consistent with a reaction at the particle surface. 

Ozdeger et al. studied the role of the nonionic emulsifier Triton X-405 (octyl-phenoxy polyethoxy ethanol) in the emulsion homopolymerization of St [99] and n-butyl acrylate (n-BA) [ 100], and in the emulsion copolymerization of St and n-BA [101]. In the emulsion homopolymerization of St, they noted two separate nucleation periods, resulting in bimodal PSDs. Although the total concentration of the emulsifier was maintained at a level above its CMC based on the water phase in the recipe, the portion of the emulsifier initially present in the aqueous phase was below the CMC due to partitioning between the oil and aqueous phases. Due to the nature of this emulsifier, the first of the two nucleation periods was attributed to homogeneous nucleation, while the second was... 

Only a few papers have appeared dealing with LRP by DT [8], and the applications are almost completely limited to the homopolymerization of styrene. In this case, it was possible to obtain good control of the final CLD, with polydispersity values as low as 1.3-1.4. Better performances are difficult with styrene, mainly because of the limited transfer activity of the iodine atoms. This is the main reason for the very poor results obtained when applying this process to the polymerization of acrylates (e.g. n-butyl acrylate) and for the complete lack of control reported for other monomers [8]. 

Fungicidal vinyl ethers 25, 30 and 32, resisted radical initiated homopolymerization. Copolymerizations of these monomers with n-butyl acrylate or methyl methacrylate were generally unsatisfactory. At low mole ratios of fungicidal vinyl ether to acrylate, copolymers could be isolated with either very low or no incorporation of the vinyl ethers. 

H5P, an a-methylstyrene derivative, seems to have a low ceiling temperature and consequently did not homopolymerize but underwent copolymerization with styrene, methyl methacrylate, and n-butyl acrylate. Based on the homopolymerization attempts, it appears that 2H5P is present as isolated monomer units in these copolymers. The co-polymerization parameters of 2H5V and 2H5P with styrene, methyl methacrylate, and n-butyl acrylate have also been determined. The results are shown in Figure 3 The copolymerization experiments were done to 5 conversions. 

Percy and coworkers [39,40] synthesized colloidal dispersions of polymer-silica nanocomposite particles by homopolymerizing 4-vinylpyridine or copolymerizing 4-vinylpyridine with either methyl methacrylate, styrene, n-butyl acrylate or n-butyl methacrylate in the presence of fine-particle silica sols using a free-radical in aqueous media at 60°C. No surfactants were used and a strong acid-based interaction was assumed to be a prerequisite for nanocomposite formation. The nanocomposite particles had comparatively narrow size distributions with mean particle diameters of 150-250 nm and silica contents between 8 and 54 wt.%. The colloidal dispersions were stable at solids contents above 20 wt.%. 

Poly(styrene-c i-t-butyl acrylate). One of the major issues with TEMPO mediated "living free radical polymerizations is the very different reactivities of st5n ene and acrylates. It has been observed that TEMPO mediated styrene homopolymerization achieve high conversion, with low polydispersity and excellent molecular weight control. In contrast acrylate homopolymerizations exhibit considerably lower conversion with much broader polydispersities. Figure 2. However, it has been shown that "living" free radical polymerization permits the synthesis of well defined... 

Lacroix and coworkers reported a reverse iodine transfer pol5mierization (RITP), where elemental iodine is used as a control agent in living radical polymerization [288]. Styrene, butyl acrylate, methyl acrylate, and butyl ot-fluoroacrylate were homopolymerized, using a radical catalyst and I2 as a chain transfer agent. Methyl acrylate was also copolymerized with vinyUdene chloride using this process. 

Fig. 2 Kinetic profiles of copolymerization of ribose-based allyloxy monomers compared to vinyloxy analogs with DEF and of homopolymerization of butyl acrylate (equimolar amount of each comonomer PI 5wt-% of Darocur 1173, 365 nm light, P = 8 mW cm ).

Beuermann S, Buback M, Schmaltz C. Termination rate coefficients of butyl acrylate free-radical homopolymerization in supercritical COj and in bulk. Ind Eng Chem Res 1999 38 3338-3344. 

Ouzineb et al. [89] carried out emulsion copolymerizations of n-butyl acrylate and methyl methacrylate with different types and concentrations of surfactants (Triton X-405 versus sodium dodecyl sulfate) to study particle nucleation and the resultant latex particle size and particle size distribution. The presence of relatively hydrophilic methyl methacrylate in the continuous aqueous phase has a significant influence on the CMC of Triton X-405. Furthermore, the relatively hydrophobic n-butyl acrylate predominates in the particle nucleation process involved in emulsion copolymerizations of n-butyl acrylate and methyl methacrylate, with the final number of latex particles per unit volume of water very similar to that of latex particles obtained from the homopolymerization of n-butyl acrylate. 

Figure 16 Microwave-assisted reversible addition-fragmentation chain-transfer homopolymerization of DMA or NIPAM and subsequent block copolymerization with NIPAM, DMA, butyl acrylate, or methyl acrylate.

Block copolymars containing PMeVE and poly(tert-Bu acrylate), poly(acrylic acid), poly(Me acrylate), or polystyrene have been prepared by Bemaerts and Du Prez by the use of a novel dual initiator 2-bromo-(3,3-diethoxy-propyl)-2-methylpropanoate. In the first step, the living cationic homo-polymerization of MeVE is performed with the acetal end group of the dual initiator as initiating site or by the ATRP homopolymerization of tert-butyl acrylate from the bromoi-sobutyrate group of the dual initiator. In the second step in the preparation of block copolymers, well-defined PMeVE-Br and pol) -tBA-acetal homopolymers were employed as macroinitiators, respectively, in the ATRP of several monomers and cationic polymerization of MeVE. 

All the acrylate resins suffer a severe risk of homopolymerization. One can even safely state that without correct stabilization these resins cannot be made. The most often applied stabilization package consists of a phenolic stabilizer such as 2,6-di-t-butyl-4-methylphenol in combination with air it is especially the oxygen in air that is required. Oxygen is a very efficient acrylate polymerization inhibitor... 

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