Radical polymerization tert-butyl acrylate

Homopolymer PS and block copolymer poly(tert-butyl acrylate)-b-styrene, prepared by nitroxide-mediated living free-radical polymerization, were utilized for the functionalization of shortened SWCNTs through a radical coupling reaction (Scheme 1.33) [194]. 

Pentadienyl-terminated poly(methyl methacrylate) (PMMA) as well as PSt, 12, have been prepared by radical polymerization via addition-fragmentation chain transfer mechanism, and radically copolymerized with St and MMA, respectively, to give PSt-g-PMMA and PMMA-g-PSt [17, 18]. Metal-free anionic polymerization of tert-butyl acrylate (TBA) initiated with a carbanion from diethyl 2-vinyloxyethylmalonate produced vinyl ether-functionalized PTBA macromonomer, 13 [19]. 

Fig. 7 (a) H NMR spectra of poly(fert-butyl acrylate) (PTBA) synthesized by free radical polymerization of tert-butyl acrylate (TBA) in the presence of benzyl mercaptan (BnSH). (b) Dependence of the number average molecular weight (M ptba) of the PTBA on the BnSH/TBA ratio as obtained from H NMR end group analysis (filled circles) and SEC (open circles) (the actual BnSH/TBA molar ratio is indicated)... 

Figure 1 Atom transfer radical polymerization (ATRP) of tert-butyl acrylate for preparation of model radical precursors.

AYD Aydin, S., Erdogan, T., Sakar, D., Hizal, G., Cankurtaran, O., Tunca, U., and Karaman, F., Detection of microphase separation in poly(tert-butyl acrylate-Z>-methyl methacrylate) synthesized via atom transfer radical polymerization by inverse gas chromatography, Eur. Polym. J., 44, 2115, 2008. 

Poly(hydroxystyrene) (PHOST) is often prepared by polymerization of 4-acetoxystyrene, followed by base-catalyzed hydrolysis (Fig. 9a). The ace-toxystyrene monomer s stability and polymerization kinetics allow production of PHOST of higher quality than is easily obtained via direct radical polymerization of HOST. The PHOST homopolymer formed thereby is then partially or fiilly derivatized with an acid-cleavable functionality to produce the final resist component. In some instances the resist polymer can be prepared in a single step by direct polymerization of the protected monomer(s) (23,45), entirely avoiding the intermediate PHOST. HOST-containing resist polymers have also been prepared by free-radical copolymerization of a latent HOST and a stable, acid-labile monomer, for example, the copolymerization of acetoxystyrene with tert-butyl acrylate, followed by selective removal of the acetoxy group (46) (Fig. 9b). 

Davis, K. A., and Matyjaszewski, K. (2000). Atom transfer radical polymerization of tert-butyl acrylate and preparation of block copolymers. Macromolecules, 33(11) 4039-4047. 

In this chapter, three examples of the application of ESR to conventional radical polymerizations based on controlled/living radical polymerizations wUl be demonstrated. The first example is estimation of the effect of chain length on propagating radicals. The second example is the detection of chain-transfer reactions on the propagating radicals in polymerization of tert-butyl acrylate (tBA). The third example is investigation of penultimate unit effects using ESR analysis of dimeric model radicals of (meth)acrylates prepared by ATRA. 

This technology has been expanded to prepare intelligent nanocapsules with temperature-responsive cross-linked shells and pH-responsive brushes on their inner walls. These nanocapsules have been prepared by the surface-initiated atom transfer radical polymerization (SI-ATRP) technique with sihca NP as the sacrificial templates. The two-step, sequential SI-ATRP procedure provided the poly(tert-butyl acrylate) (PtBA) brushes on the inner walls of the temperature-responsive cross-linked poly(A-isopropylacryl-amide) (PNIPAA) shells. Then the ester groups in the nanocapsules were transformed chemically into carboxyl groups after etching the silica templates with HF (Mu and Liu, 2012). 

Becer, C.R., Paulus, R.M., Hoogenboom, R., and Schubert, U.S. (2006) Optimization of the nitroxide-mediated radical polymerization conditions fm styrene and tert-butyl acrylate in an automated parallel synthesizer. Journal of Polymer Science, Part A Polymer Chemistry, 44,6202-6213. 

For the polymerization of tert-butyl acrylate, the monomer consumption followed the first-order kinetics, while that of MMA could be described with a kinetics model that includes the persistent radical effect. The control over the reaction could be preserved for monomer conversions of up to 90%, and poly(methyl methacrylate) s (PMMAs) with narrow molecular weight distributions (PDI below 1.3) were obtained. Conventional experiments with an oil bath showed a limited reproducibility and furthermore failed to yield polymers with similar narrow molecular weight distributions (for high conversions). This observation was refereed to the superiority of the uniform, noncontact, and internal heating mode of micro-wave irradiation. 

A radical polymerization has been developed by liu et al. [46] to prepare polymer or copolymer grafted SWNTs. The radical chains of polystyrene and poly(tert-butyl acrylate-b-styrene) with well-defined molecular weights and polydispersities, prepared by nitroxide-mediated free-radical polymerization, were successfully used to... 

Ananchenko G, Matjgaszewski K. Controlled/living radical polymerization of tert-butyl acrylate mediated by chiral nitroxides. A stereochemical study. Macromolecules. 2002 35 8323-8329. 

Other vinyl monomers, such as acrylonitrile, methacrylonitrile, tert.-butyl vinyl ketone and methyl isopropenyl ketone, polymerize at 203 K, i. e. most probably by non-radical mechanisms. Even here, conversion of monomer to polymer is not complete, and utilization of the initiator is low. Only the polymerization of acrylate momomers proceeds to full monomer consumption at low temperatures. Additional monomer, even when introduced after some delay, is also polymerized. This indicates that a part of the active centres remains living for some time. However, the number of high-molecular-weight chains is lower than the number of added initiator molecules. At the same time, initiation is very rapid [163]. 

Oxman et al., smdied controlled, sequentially curable cationic/free radical hybrid photopolymerization of diepoxide/acrylate hybrid material with the aid of photodifferential scanning calorimetry. The polymerizations were carried out in the presence of various concentrations of either ethyl-4-dimethylamino benzoate or 4-tert-butyl-N,N,-dimethylaniline as electron donors and camphoquinone/diphenyliodonium hexafluoroantimonate as the sensitizing system. The results showed that the free-radical acrylate reactions always precede the cationic epoxy polymerizations. 

The hydrosols may be either linear, graft or branched polymers. The linear acrylic hydrosol polymers can be conveniently prepared by a conventional free radical solution polymerization process. Useful examples of initiators include dibenzoyl peroxide, hydrogen peroxide and other peroxy compounds such as tert-butyl peroxyp-ivalate, ferf-butyl peracetate, ferf-butyl peroctoate, and azo compounds such as 2,2 -azobisisobutyronitrile. The solvent used for the polymerization should be miscible with water so that the polymer can be conveniently inverted. 

When NMAAm was polymerized in benzene at room tonperature by using di-tert-butyl peroxalate(DBPOX) as the initiator, the polymerization mixture afforded the ESR spectrum shovm in Fig. 1 a. This three line spectrum is characteristic of the propagating radicals of acrylic monomers and assignable to the polyfNMAAm) radical(III). The 1 2 1 triplet is due to the fact that the coupling constant (ca. 25G) of the a-hydrogen is similar to that of one of the two p-hydrogens and that the other p-... 

In many cases, azobis(isobutyronitrile) (AIBN) is employed as radical initiator. The polymerization conditions, in particular solvent, depend mainly on both, solubility of the starting sf monomers and choice of comonomer. To give just a few examples, copolymers of dodecafluoroheptyl methacrylate with methacrylic acid could be synthesized in dioxane due to the solubilizing effect of methacrylic acid [66], copolymers of sfMA-H2F8 and sfMA-H2F4 with styrene could be prepared in toluene [35], and copolymerizations of i/methacrylates with butyl acrylate, hydroxy-butyl acrylate, and styrene were performed using tert-butyl peroxyacetate as initiator in methyl amyl ketone [31]. 

Vinyl-functional alkylene carbonates, useful in the preparation of polymers that contain alkylene carbonate pendant groups, can also be prepared from GC. Two examples are the reaction of GC with maleic anhydride and acryloyl chloride to produce the acrylate-functional cyclic carbonates (3 and 4, respectively. Scheme 24). Although the transesterification of alkyl esters such as dimethyl maleate or methyl acrylate by reaction with GC represents an obvious means of obtaining the above materials, the temperatures required of such processes (>100°C) result in unwanted polymerization of both the reactant and product species, even in the presence of well-known radical inhibitors such as 2,6-di-tert-butyl-p-cresol or phenothiazine. In addition, the synthesis of vinyl-functional alkylene carbonates is greatly complicated by the fact that such materials cannot be purified by distillation and must be stored at temperatures < 0 ° C in the presence of a... 

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