Macromonomers polycondensable groups

Like the telomerization process, ATRP enables the synthesis of two different types of macromonomers either with a polymerizable double bond or with a polycondensable group. As depicted in Sect. 3.1 on the design of the macromonomers, the polycondensable groups also comprise groups that afford ring-opening polymerization. 

NMP leads to a macromonomer structure by modification of either the a position or the a> position, i.e., the aminoxyl function. The a position is brought by the intiator and a chemical modification usually leads to macromonomers with two polycondensable groups. Moreover, the functionalization of the aminoxyl function will lead to macromonomers with... 

Milkovich et al.18 reacted living polystyrene with epichlorohydrin and, after hydrolysis of the epoxide ring, obtained quantitatively a macromonomer possessing at one chain end two adjacent hydroxy groups which can subsequently add to diisocyanates to yield graft polycondensates ... 

Furthermore, the group of Deimede [338-340] performed the synthesis of a-dicarboxy end-functionalized PS macromonomers by using ATRP (Scheme 72). Further polycondensation with dihydroxy end functionalized polyethylene oxide) led to alternating branched PS/poly(ethylene oxide) poly(macromonomers) (Scheme 72). These novel amphiphilic compounds afforded the formation of stable micelles, especially in THF or dioxane. 

Combination of the head and end group control provides a novel synthetic route for the synthesis of a-hydroxyl-co-methoxycarbonyl asymmetric telechelic PIB H0PIBC(R)(R )C00CH3 (a condensation macromonomer). Hydrolysis of the methoxycarbonyl end group results in the formation of a-hydroxyl-co-carboxyl asymmetric telechelic PIB HOPIBC(R)(R )COOH, while ester dcoholysis provides a method for polycondensation reactions of PIB. In the present publication we report the synthesis of these materials. 

In conclusion, it has been shown that it is possible to carry out the straightforward transformation of a cheap solid industrial by-product like lignin into a liquid polyol mixture that can be employed directly as a macromonomer for the fabrication of polyurethane foams, and indeed of any other macromolecular material based on polycondensation reactions involving OH groups. 

Polycondensation techniques have been employed for the synthesis of macromonomers. Depending on the nature of the functional end group the copolymerization with comonomers can be performed with addition polymerization techniques, giving rise to very interesting graft copolymer structures. 

Two reactive vinyl groups in the molecule of macromonomer 3 are attached to the silicon atoms that are located in one of the major corporal diagonals of the cube. Formation of the structure (Tg) during the course of hysrolytic polycondensation is not a process sufficiently explicit in all particulars. Therefore Scheme 2 presents, in some detail, one of the possible routes of chemical transformations leading to the... 

Figure 7.1 shows a schematic chemical synthesis of different chanicals required to prepare linear Seesaw-type macromonomer chains with two azide end groups and one middle alkyne group as well as the self-polycondensation via cUck chemistry between azide and alkyne. 

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