Styrene, graft copolymers with poly ethyl

Pan et al. prepared a macroinitiator by chloromethylation of a commercially available AB block copolymer of poly (styrene-fe-ethylene-co-propylene) (SEP) and used it as a macroinitiator for the ATRP of ethyl methacrylate (EM A) [302]. The kinetic plot showed little evidence of termination during the reaction and the molecular weight of the graft copolymer increased linearly with the monomer conversion, resulting in a final Mn=73,200 and Mw/Mn=1.22. The weight ra-... 

The most important compounds are polyetherols, polyesterols, and graft polyols (Figure 1). Polyetherols are the most common polyols and most commercial products are made chiefly from ethylene oxide and propylene oxide. Polyesterols are widely used in elastomeric polyurethanes. Typical compounds are aliphatic polyesters, such as poly(ethyl-ene adipate), made so that there are only hydroxyl end groups, with no residual acid groups. Graft polyols (also called polymer polyols) consist of a matrix of a conventional polyol, which also contains rubbery (such as styrene/acrylonitrile copolymer) particles chemically bound to polyol molecules. These grafted particles reinforce the final polyurethane, giving improved physical properties. 

SGI nitroxide was attached to latex particles made of poly(styrene-co-chloromethylstyrene) of 60 nm diameter previously prepared via atom transfer radical addition [83]. Microspheres grafted with the homopolymer poly (2-dimethylamino ethyl acrylate) (PDMAEA), as well as block copolymers poly (styrene-h-DMAEA) and poly(butyl aciylate-h-DMAEA) were prepared by Sl-NMP in DMF at 112 C, with the initial addition of free SGI to ensure polymerization control. 

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