Macromonomers synthesis procedures

Structural control of polymer terminal has been extensively studied since terminal-functionalized polymers, typically macromonomers and telechelics, are often used as prepolymers for synthesis of functional polymers. Various methodologies for synthesis of these polymers have been developed however, most of them required elaborate and time-consuming procedures. By selecting... 

A similar procedure was also used for the synthesis of methacrylate functional poly(a-MeS) [80]. Thus, 31 was used in conjunction with SnBr4 in CH2C12 at -78 °C, to obtain the macromonomer with Mns substantially (-50%) higher than the theoretical value. This was probably due to the formation of terminated low MW oligomers with indanyl end group structure. The eliminated proton was as-... 

The synthesis of MA-PIB macromonomers by three different methods, which were claimed to be less cumbersome than that above, was reported by Maenz and Stadermann [105]. The first procedure, as shown in Scheme 12, involved alkylation of phenol by PIB olefin followed by reaction with methacrylic acid. 

In the first part of this review we shall consider the various pathways that have been used (or attempted) to synthesize macromolecular monomers. We shall critically discuss the efficiency of the methods that have been proposed, together with the procedures used for the characterization of the species obtained. In the second part we shall describe the various attempts to homopolymerize macromonomers and to use them in copolymerization reactions to obtain graft copolymers. We shall include some potential applications of macromonomers as intermediates to the synthesis of new polymeric materials that have been proposed. 

Depending on the composition of the monomer feed and the polymerization procedure, different types of heterogeneities may become important. For example, in the synthesis of tailor-made polymers telechelics or macromonomers are frequently used. These oligomers or polymers usually contain functional groups at the polymer chain end. Depending on the preparation procedure, they can have a different number of functional end groups, i.e. be mono-, bifunctional, etc. In addition, polymers can have different architectures, i.e. they can be branched (star- or comb-like), and they can be cyclic. 

The 80/20 (wt/wt) methyl methacrylate (MMA) n-butyl acrylate (BA) macromonomer was prepared in the following manner. To a 3000-mL flask 440.1 g MMA, 200.0 g BA, and 150.0 g methyl ethyl ketone (MEK) were added. The mixture was stirred and heated to reflux under a nitrogen blanket. After a 10-min hold, 30.0 g MEK, 0.140 g Vazo-67, and 0.050 g Co(dimethylglyoxime-BF2)2 were added to the flask. After a 5-min hold, 359.9 g MMA, 200.0 g MEK, and 1.90 g Vazo-67 were added over a 3.5-h period. The mixture was held 1 h at reflux after the feed. Subsequently, 150.0 g MEK and 1.00 g Vazo-52 were feed over an hour. The mixture was held for 1 h at reflux. The mixture was then allowed to cool to room temperature. A more detailed procedure and the Co(dimethylglyoxime-BF2)2 synthesis are given in reference 18. 

Synthesis of Methoxy-PEG-VB macromonomer was done by anionic ring-opening polymerization at room temperature and under argon gas" and could be accomplished using the following procedure ... 

With all respect due to the experimental skill of the authors cited, it must be confessed, in all candor, that synthesis of the starting macromonomer by that procedure was not quite simple and sufficiently effective. In the present study, we... 

These procedures have also been applied to the synthesis of 1,1-dipheny-lethylene-functionalized polybutadiene macromonomers (79) [208, 209]. The general reaction scheme is shown in Eq. (45) ... 

The preparation procedure of narrowly distributed Seesaw-type macromonomer triblock copolymers, poly(tert-butyl acrylate)-polystyrene-poly(terr-butyl acrylate) (PtBA-PS-PtBA), with one alkyne group in the center of the PS block and one azide group at the end of each PtBA block is similar to that of macromonomer polystyrene homopolymers. The schematic synthesis of PtBA-PS-PtBA triblock copolymer is shown in Fig. 3.8. The corresponding DP values were calculated from area ratio of corresponding peaks in NMR spectrum, as shown in Fig. 3.9, and the molecular parameters of our obtained triblock copolymers macromonomer PiBA-PS-PtBA with different St and tBA molar contents and molar masses are summarized in Table 3.2. 

Two-step procedures have sometimes been found more suitable for the synthesis of macromonomers. With poly(ethylene oxide) or poly(caprolactone), for instance, the living polymer has been protonated and reacted thereafter with protected esters or amines, fitted with a polymerizable unsaturation (Scheme 28). High yields can be attained, and no side reactions have been observed. 

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