Macro-monomer

Microgels may also be produced by dispersion polymerization of multifunctional monomers [276, 277]. Kim et al. synthesized microgels by copolymerization of acrylamide with acryloyl terminated polyethylene glycol macro-monomers in ethanol or in selective solvents [276]. The macromonomer acted... 

In order to keep polyamides soluble in relatively apolar solvents, the use of flexible (macro)monomers such as a, co-(diaminopropyl)polydimethylsiloxane [52] or oligoethyleneglycol-based diamines [53, 54] has been proven to be a successful approach (Fig. 10). Poly condensations of dimethyl adipate with a variety of diamines were successful in bulk and at moderate temperatures between 60 and 100 °C (reaction A in Fig. 10). The low temperatures (60-100 °C) that suffice in these polymerizations also allow the use of monomers that are thermally instable, such as diethyl fumarate [53]. Moreover, multifunctional amines could be regioselectively polymerized up to molecular weights of 9 kDa, making lipase catalysts a valuable tool for the preparation of well-defined polyamides that can be further functionalized with active groups. 

In summary, stable fibrillar aggregates were obtained from all macro monomers A-E, which had end groups capable of N—H 0=C type hydrogen bonding. 

Hawker and Frechet in 1992 [18]. However, only in the last 4 years has the maturing of dendrimer synthesis and related characterization methods made it possible to study dendron (macro) monomers and to exploit their potential for the synthesis of dendron-bearing polymers. 

Additional Step 2 polymer analogues containing hydrophilic arylsiloxy-con-taining macro-monomers, (1), were prepared by Salamone [1],... 

Preparation of graft-co-polymers from poly(meth)aciyloylguanidines after their modification (obtaining of macro-monomers) followed by co-polymerization of macro-monomers. 

Design of Thermoresponsive Materials by ATRP of Oligo(ethylene glycol)-based (Macro)monomers... 

The number of studies about syntheses and applications of macro-monomers has been increasing since macro-monomers are very useful in the preparation of various kinds of functional graft copolymers having well-defined structures. One can clarify the mechanism of polymerization of macro-monomers in comparison with small monomers by the ESR method, which is also a good example of the application to... 

Here [M] is the concentration of the macro-monomer. Tsukahara et al. [7] have observed ESR spectra of propagating radicals during the polymerization of a styrene macro-monomer having a metacyloyl end group. 

Figure 7.6 shows typical examples of the ESR spectra for a macro-monomer MM A. The five and four (5+4) lines measured at 60 C and -196 C are due to the MMA propagating radical described in the previous section. From the ESR signal, the concentration of the propagating radical of the macro-monomer [M ] can be evaluated. The value of 1%, was determined to be 37 (L/mol s). Rate constants for the polymerization of the MMA monomer at different conditions are shown in Table 7.1. It is seen from this table that kp is considerably decreased in the macro-monomer system compared to polymerization of the small monomers. This is clearly due to the high viscosity of polymerization media and the specific multi-branched structure of the propagating radicals. 

Fig. 7.6 Change of ESR spectra of MMA macro-monomer propagating radicals by quenching and aging (a) at 60°C, (b) at -196°C after (a), and (c) at 23°C after (b). The spectra were measured at the temperature of the respective heat treatment. The figure is adapted from [7] with permission from the American Chemical Society...

For the preparation of nano- and microgels, reactive monomers and macro-monomers are loaded into nano- and microreactors, which are usually emulsion droplets [23] or cavities generated by soft lithography [24]. After cross-linking the macromonomers inside of these nano- and microtemplates... 

The molecular weight of the different blocks can be controlled by adjusting the polymerization time and the substitution pattern (degree of alkyl substitution) of the monomers and macro monomers. 

The ability of anionic polymerization to polymerize macromonomers has been demonstrated. co-(Methacryloyloxy)-PS macromonomers could be homopolymerized anionically to high yield using diphenylmethyl potassium as an initiator. Similar results could be obtained for co-styryl-PS macro monomers. These cylindrical bmsh species served as models for physicochemical studies. The major difficulty of this reaction... 

The PUs properties depend strongly on their macromolecular structure, i.e. the nature and functionality of their constituting (macro)monomers. In general the... 

Tanaka et al. used NPLC and RPLC to determine CCD of PMMA- -PS with different compositions and conversions synthesized from the copolymerization of methyl methacrylate and co-p-vinylbenzyl polystyrene macro monomer [ 158]. The good agreement between CCD obtained by both HPLC modes showed that the molecular weight effect on the CCD is negligible. As the macromonomer content increases, the CCD becomes sharper. These results are in accordance with the theoretical predictions. As the conversion increases at the same feed composition, the CCD becomes broader towards the low macromonomer content side, which is in contrast to the CCD of the samples obtained previously from oo-methacryloyl polystyrene macro monomer [159]. They also showed that the CCD is broadened as the graft length increases, in copolymer samples with a similar composition, in accordance with the theoretical prediction [159]. 

Most work on REMP was done with COE (8) or cyclooctadiene (COD) (9) but functionalized monomers can also be used. A dendronized macro-monomer 10 (Figure 1.4) has been used under REMP conditions, leading to the formation of cyclic nanostructures with a diameter of 35-40 nm [40]. Recently, a REMP-derived cyclic macro-initiator derived from monomer 11 was used to prepare cyclic brush copolymers by combining REMP with triazabicyclodecene-catalyzed ring-opening polymerization of a cyclic ester [41]. Furthermore, REMP processes were developed for the synthesis of functional cyclic polymers, cyclic polymer brushes, and cyclic gels [42, 43]. 

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