Macroinitiators polarity

In the homogeneous MMA polymerization with 1-32 (Y = CH3)/CuBr/L-9 (R = n-Pen), the rate increased in the order xylene < DMB < DPE,179 probably due to the differences in the dielectric constant and coordination ability of the solvents. With the homogeneous Ru-1 catalyst, the polymerization of MMA was faster in a polar solvent such as CPI2C12 than in toluene.159 A more detailed analysis on solvent effects was carried out by end-capping a polymer radical with hydroxyl-TEMPO, where the radical intermediate was generated from bromide macroinitiators via CuBr/L-4 catalyst.242 A polar solvent such as butyl acetate increases the radical-generation rate from poly(acrylate)s but not from polystyrene. On the other hand, no rate increase was found for both macroinitiators in DMF, which is... 

The self-condensing copper-catalyzed polymerization of macromonomer of poly(tBA) with a reactive C—Br bond (H-6) affords hyperbranched or highly branched poly(tBA).447 Copolymerization of H-1 and TV-cyclohexylmaleimide induced alternating and self-condensing vinyl polymerization.448 The residual C—Cl bond was further employed for the copper-catalyzed radical homopolymerization of styrene to give star polymers with hyperbranched structures. Hyperbranched polymers of H-1 further serve as a complex multifunctionalized macroinitiator for the copper-catalyzed polymerization of a functional monomer with polar chromophores to yield possible second-order nonlinear optical materials.325... 

In the area of novel materials CMU protected (co)polymers prepared by ATRP except with CCI4 initiator and telechelic polymers prepared by CRP with MW > 20,000 (49) copolymers with a tme gradient segment (30) polar ABA block copolymers, (30) and well defined graft copolymers and segmented copolymers with one or more CRP blocks where the macroinitiator had been prepared by another polymerization process. (36) In addition, the use of tethered initiators allowed synthesis of hybrid core/shell copolymers. Pending applications disclose other novel polymeric materials. 

In the second method, a propagating active center is transformed directly to another active center with different polarity. Once the first segment is obtained, it is utilized as a macroprecursor for the formation of macroinitiator (Figure 6). 

The material so frinctionalized constitutes a multiarm macroinitiator for ATRP processes. From this core was grown a polar corona by foe polymerization of polyethylene glycol methacrylate (PGG-DP - 7 ) using bis-tr henyl ho hiiie nickel n bromide as foe catalyst in tolumie (95 C, 40% solids, initiator/catalyst = 0.23, nickel/monomer = 0.019 ). The anqrhiphilic product was isolated by prec itation and foe polymer data listed in Table 1. Hoe GPC aiuilysis is particularly troublesome, since foe materials stick to foe column resulting in very low estimates for the molecular weight From H-NMR, foe degree of polymerization/arm was estimated at 14 and foe measured Rfc (THF) = 10.1 nm ( 20% size increase relative to the polystyrene core). 

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