P-chloromethylstyrene

Various substituted styrenes have been also polymerized by NMP. These include 1 03-1 07, p-chloromethylstyrene (108), p-halostyrenes, and p-aceloxystyrene. Vinyl pyridines (e.g. 109) are amenable to NMP21 and may be quaternized post-polymerization to provide water-soluble polymers. 

A combination of TEMPO living free radical (LFRP) and anionic polymerization was used for the synthesis of block-graft, block-brush, and graft-block-graft copolymers of styrene and isoprene [201]. The block-graft copolymers were synthesized by preparing a PS-fo-poly(styrene-co-p-chloromethylstyrene) by LFRP [Scheme 110 (1)], and the subsequent re-... 

Various halogenated polymers are used as the polymeric initiator for ATRP, for example, vinyl chloride-vinyl chloroacetate and styrene-p-chloromethylstyrene copolymers, bromi-nated butyl rubber, and chlorosulfonated polyethylene [Bomer and Matyjaszewski, 2002 Coskun and Temuz, 2003], (The vinyl chloride units have much lower reactivity for ATRP compared to the vinyl chloroacetate units because of steric reasons.) The density of grafting is adjusted by varying the copolymer composition. 

Using the grafting-from method with NMP requires the synthesis and (co)polymerization of monomers that contain the nitroxide group [Hawker et al., 2001]. A halogen-containing monomer such as vinyl chloroacetate or p-chloromethylstyrene is reacted with an HO-containing alkoxyamine to yield a vinyl alkoxyamine, which is used as a NMP initiator to... 

A vinyl monomer that acts as an antioxidant is 4-anilino-N-(4-vinylbenzyl)aniline, which can be prepared from p-aminodiphenyl-amine and p-chloromethylstyrene. Similarly, the reaction product of p-hydroxydiphenylamine and p-chloromethylstyrene, which is 4-anilinophenyl-4-vinylbenzyl ether is useful in this way (72). The synthesis is shown in Figure 6.11. 

Saegusa et al. [81] reported on the grafting of poly (ethyleneimine) on poly(p-chloromethylstyrene) (PS-g-PEI). 

The self assembly of polymers in the solid state, using polystyrene scaffolds with pendant 2,6-diamino-pyridine (DAP) units has been extensively described by Rotello et al. [224] (Sect. 3.3). Two different polymers were investigated either a homopolymer, functionalized with the pendant DAP units, or a PS-PS diblock copolymer, in which one block only was functionalized with the DPA units via a p-chloromethylstyrene block (Fig. 67). In order to study the effect exerted by the hydrogen-bonding moieties onto the microphase separation, a series of polymers with different fractions of... 

DUV exposure of poly( p-substituted styrenes), such as poly( p-chloro-styrene), poly( p-chloromethylstyrene), and poly( p-hydroxystyrene) [poly(p-vinylphenol)] (structure 3.11), in air leads to photocross-linking and photooxidation. Consequently, DUV hardening is applicable to resists based on these polymers as well as novolac-based resists (168, 169). 

Hawker et al. [95] and Fukuda et al. [96] both reported on the copolymerization of St with various monomers in 1996. Hawker reported copolymerizations with nBA, MMA, and p-chloromethylstyrene (CMSt), while Fukuda focused on several acrylates, 9-vinylcarbazole, and acrylonitrile (AN), and succeeded in preparing block-random copolymers of St with AN (details below). Neither group found the polymerizations to be well-controlled when low concentrations of St were present in the comonomer feed. However, since then, NMP has been used extensively to prepare copolymers. Pozzo et aL copolymerized St with 4-vinyl pyridine (VP), initiated by benzoyl peroxide (BPO) and using TEMPO as the radical mediator [97]. After purification, the copolymer was reacted with spiro [fluorenecyclopropene] to prepare photochromic copolymers with controlled molecular weights (Scheme 6). 

Ac = Polyacrylamide Cycl = Cyclodextrin PE = Polyethylene PEO = Oxidized polyethylene PS = Polymer derived from p-chloromethylstyrene PS,b = Polymer derived from styrene and (7-bromoheptyl)styrene PS,b = Polymer derived from styrene and 4-bromobutyl)styrene PS,c = Polymer derived from styrene, p-chloromethylstyrene and divinylbenzene PS,f = Polymer derived from crosslinked polystyrene and polypropylene fibers. 

RAFT has also been used to produce graft polymers. The grafting from method is achieved by reacting a halogen-containing polymer such as styrene-p-chloromethylstyrene copolymer with sodium dithiobenzoate to obtain a polymeric dithioester, which is an initiator... 

Bachhawat N, Gowda LR, Bhat SG (1996) Single step method of preparation of detergent perme-abUized Kluyveromyces fragilis for lactose hydrolysis. Proc Biochem 31(l) 21-25 Bahar T, Tuncel A (2004) Concanavalin A attached poly(p-chloromethylstyrene) beads for gly-coenzyme separation. J Appl Polym Sci 92(4) 2116-2124 Bailey JE, OUis DE (1977) Biochemical engineering fundamentals. McGraw-HUl, New York, 753 pp... 

Cyclic PSs have been prepared in a similar way. An a,(D-heterodifunctional PS is first prepared anionically starting from lithiopropionaldehyde diethylacetal as initiator. After conversion of the styryl anion to diphenylethenyl anion, the PS is deactivated by p-chloromethylstyrene. In a second step, the acetal group is first converted into... 

Two new synthetic methods for the preparation of functional polymers containing 2-oxazoline pendant groups were developed. The first concerns the synthesis of m- and p-vinylbenzyl ethers of 2-(p-hydroxyphenyl)-2-oxazoline, followed by their radical poljnnerization. 2-(p-Hydroxyphenyl)-2-oxazo-line was reacted with a mixture of m- and p-chloromethylstyrene (60% m and 40% p) under phase transfer catalysis conditions at room temperature. The m-and p-vinylbenzyl ethers of 2-(p-hydroxyphenyl)-2-oxazoline obtained were separated by selective crystallization from methanol. Radical polymerization of these ethers was carried out in dioxane at 60 C, giving polymers with pendant 2-oxazoline groups. 

P(S- - -BMA) and PS-6-P(S-g - -BMA) block graft copolymers were prepared using TEMPO living and atom transfer radical polymerization techniques (45). The backbone of the P(S-g-f-BMA) copolymer was synthesized by TEMPO living radical copolymerization of styrene and p-chloromethylstyrene. Subsequently, the chloromethyl groups in the presence of CuBr and bipyridine were used as initiation sites of ATRP of t-BMA. In the case of PS-6-P(S-g- -BMA) copolymer, the synthesis was performed in a similar way. 

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