Oligomers reactive macromonomers

One of the primary thrusts in oligomeric research has been in developing oligomers as intermediates in preparative polymer chemistry. Research in the chemistry of chain-ended functional oligomers is important to preparative polymer chemistry because of the use of oligomers as macromonomers and telechehcs, and for their other reactive properties [1,2]. 

Macromonomers used in RE include poly- or oligomers with a reactive double bond. Because of mostly steric factors, macromonomers usually display a weaker tendency to homopolymerization in comparison with monomers. A disadvantage of macromonomers used in RE is that owing to lower volatility the ungrafted portion cannot be removed from the melt during the stage of degassing. 

LCB results from the copolymerization of ethylene or propene with vinyl-terminated polymer formed during the polymerization. Since vinyl double bonds are more reactive in copolymerization than other types of double-bond end groups, LCB is increased under conditions that generate higher vinyl contents. This can be accomplished by choice of initiator and reaction conditions. Tandem polymerization is also useful, such as by using two initiators, one of which produces a vinyl-terminated oligomer (referred to as a macromonomer or macromer) [Komon and Bazan, 2001 Quijada et al., 2001 Wang et al., 2000]. 

Oligomers and polymers with reactive functional groups have been used extensively to prepare a great variety of polymeric materials. In many cases the behavior of these functional homopolymers is largely dependent on the nature and number of functional groups. In a number of important applications the functional groups are located at the end of the polymer chain macromolecules with terminal functional groups are usually termed telechelics or macromonomers . To characterize them it is necessary to have information not only about their molar mass but also on their functionality. 

As mentioned in the introduction, the synthesis of telechelics is important to preparative polymer chemistry because of their use as macromonomer precursors (and therefore graft copolymer and network precursors), as precursors to block copolymers, and as the basis of reaction injection molding. Some general reviews on telechelics include those of A they and Heitz. In addition, the synthesis, reactions and properties of acetylene-terminated oligomers were recently reviewed.An extensive discussion of this class of reactive polymers is the subject of a recent book. ... 

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