Poly-n-hexylisocyanate

Living poly(n-hexylisocyanate) was previously prepared by titanium-catalyzed coordination polymerization as described by Rattan [1],... 

Other encapping agents were used to functionalize poly(n-hexylisocyanate) in the current investigation. (s)-( )Acetopropionyl chloride was used to prepare an optically active terminus, (I), while suberoyl chloride was used to prepare the corresponding acid chloride terminus, (II). 

Figure 10. CD spectra of poly(n-hexylisocyanate) (poly-85) dissolved in optically active solvents at 20 °C. Ultraviolet spectrum (bottom) shown only for (A)-2-chlorobutane (polymer concentration 1.9 mg/mL). (Reprinted with permission from ref 171. Copyright 1993 American Chemical Society.)...

Figure 12.15 Low-shear viscosity of poly-n-hexylisocyanate (a) in toluene for polymer molecular weights (left to right) 3000, 1100, 480, 250, 135, 110, 67, 38, 19, and 11.5 kDa, and (b) in CH2CI2 for polymer molecular weights (left to right) 3000, 1100, 480, 250, 135, 67, 35, and 25 kDa, using results of Ohshima, et a/. (41,42).

Figure 12.32 Transition concentration c+ as a function of polymer molecular weight for poly-n-hexylisocyanate in (O) CH2CI2 and ( ) toluene, based on fits to data of Ohshima, et a/.(41,42). The solid line represents a power law...

To prepare uniform star polymers, click reactions have become increasingly important. The focus in this section is on star polymers made with the help of the copper-catalyzed azide-alkyne Huisgen cycloaddition, which is one of the most commonly used click reactions in polymer science. Satoh et al. used this reaction to attach 2-ethyl-2-[(prop-2-yn-l-yloxy)methyl]propane-l,3-diol onto the co-chain end of a poly(n-hexylisocyanate)-PEG block copolymer [64]. For the formation of three-arm star polymers, the introduced hydroxy groups were used as initiators for the ROP of e-caprolactones (Scheme 28). 

FIGURE 1.14 Viscosity as a function of polymer concentration of a solution of a 50 50 random copolymer, poly(w-hexylisocyanate-co-n-propylisocyanate) (M , =41,000 g/mol) in toluene, encompassing the isotropic, biphasic, and anisotropic (liquid crystal) regimes. (Adapted from Aharoni [1980a].)... 

Figure 22 Chemical structures of (a) poly(hexylisocyanate) (d) poly(N,N -di- -hexylcarbodiimide) and (e) poly[(R/ S)-N-(l-phenylethyl)-N -methylcarbodiimide)]. (b) and (c) show the synthetic scheme of the removal of the ester functions of poly(isocyano-L-alanine-L-alanine) and poly(isocyano-L-alanine-L-histidine), respectively.

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