Semitelechelic, polymer preparation

Methoxy poly(ethyleneglycol) (mPEG) was the most frequently used semitelechelic polymer for over 2 decades. It has been successfully used for the modification of various proteins, biomedical surfaces and hydrophobic anticancer drugs (for reviews see References [3,9,10]. Recently, a number of new semitelechelic (ST) polymers, such as ST-poly(A -isopropylacry-lamide) (ST-PNIPAAM) [11-15], ST-poly(4-acryloylmorpholine) (ST-PAcM) [16], ST-poly(A-vinylpyrrolidone) (ST-PVP) [17], and ST-poly[A-(2-hydroxypropyl)methacrylamide] (ST-PHPMA) [18-21] have been prepared and shown to be effective in the modification of proteins or biomedical surfaces. 

Functionally terminal polymers are valuable material intermediates. The di- and polyfunctional varieties (telechelic polymers) have found theoretical (e.g., model network) and commercial (e.g., liquid rubber) applications (1, ). On the other hand, macromolecules with a functional group at one chain end (semitelechelic polymers) have been used to prepare novel macromolecular monomers (Macromers ), as well as block and graft copolymers ( -8). 

The functional semitelechelic HPMA polymers can be readily prepared by free radical polymerization in the presence of functional mercaptans. The functional groups and chain length of the ST polymers can be controlled by the choice of a particular mercaptan and the reaction conditions. ST HPMA polymers can be used for the modification of proteins... 

Medina et al. (1) photodimerized maleimide derivatives, (I), as a method for preparing semitelechelic silicone hydrogel polymers useful as for lens coatings as illustrated in Eq. (1). 

Maynard and coworkers synthesized Poly(ethylene glycol) methyl ether acrylate (PEGA) via RAFT polymerization and dithioester functional groups at the chain end, which were reduced via aminolysis and reacted with divinyl sulfone to afford semitelechelic vinyl sulfone polymers. Thiol-ene reaction was then used to prepare conjugates between the vinyl-terminated polymer and a... 

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