Crown containing copolymers

Fig. 6. Isothermal phase transitions from the phase separated to homogeneous state of the aqueous solution of the copolymer containing 11.6 mol % pendant crown ether groups by the addition of (O) potassium and (9) sodium chlorides at 32 °C and 37 °C. Polymer concentration was 1 mass %...

These two macromonomers were subsequently copolymerized with styrene to yield graft copolymers 84) containing crown ethers in their side chains. 

Copolymers containing alternating l,4-bis(phenylethenyl)benzene, l,4-bis(phenylethenyl)-2,5-dimethoxybenzene or l,5-bis(phenylethenyl)naphthalene chromophores, and dibenzo-24-crown-8 spacers within the polymer backbone, best represented by 87, showed blue light emission in solution, and tunable photoluminescence and electroluminescence depending on the structure of the chromophore. Blends of these copolymers with a small amount of poly(ethylene oxide), and lithium salt as active layers, form efficient light-emitting electrochemical cells <2003JMC800>. 

The principle of cyclopolymerization has been applied to the synthesis of macrocyclic ether-containing polymers which may simulate the properties of crown ethers. l,2-Bis(ethenyloxy)benzene (a 1,7-diene) and l,2-bis(2-ethenyloxyethoxy)benzene (a 1,13-diene) are typical of the monomers synthesized. Homopolymerization of the 1,7-diene via radical and cationic initiation led to cyclopolymers of different ring sizes homopolymerization of the 1,13-diene led to cyclic polymer only via cationic initiation. Both monomer types were copolymerized with maleic anhydride to yield predominantly alternating copolymers having macro-cyclic ether-containing rings in the polymer backbone. 

Polymeric catalysts containing fixed crown fragments were synthesized by condensation of hydroxymethyl- or co-hydroxynonyl-18-crown-6 with a chloromethylated copolymer of styrene and DVB (1 %) [88]. The catalytic activity of polycrown ethers in the nucleophilic substitution of J , Br, CN , SCN in sodium salt of methanesulfonic... 

PAMPS and its random copolymer containing 18-crown-6 (PAMPS -co-crown), are used to further study the nonelectrostatic contribution to desorption force [56]. The primary structures of polymers are shown in Scheme 30.5. As shown in Fig. 30.12, the typical force curves of PAMPS with a plateau are obtained from amino-modified quartz in the buffer of water. The long plateau suggests that the desorption process of the PAMPS chain from the substrate is smooth and that it adopts a train-like conformation at the interface and the desorption force remains about 120 pN. The desorption-adsorption process is in equilibrium in the experimental time scale, which is confirmed by the constant desorption force when changing the stretching velocity. The desorption force of PAMPS from the amino-modified quartz has been... 

Like anion exchangers, cation exchangers are divided into polymer-based cation exchangers (PS-DVB, EVB-DVB, polymethacrylate, and polyvinyl copolymers), latex-agglomerated cation exchangers, silica-based, and other (e.g., crown ether, aluminia materials).Modern cation exchangers contain sulfonic, carboxylic, car-boxylic-phosphonic, and carboxylic-phosphonic-crown ether functional groups. 

Initial qualitative evidence that copolymer 54, which contains both calix[4]pyrrole and crown ether subunits, could extract chloride salts into organic media came from a visual test involving a water-soluble dye, 57, that contains a chloride counteranion. Treatment of an aqueous solution of the dye (25.5 mM) with a CH2CI2 solution of copolymer 54 (effective concentration of the calix[4]pyrrole and crown ether repeat units was 1.56 and 1.22 mm, respectively) resulted in a colored organic phase. 

New diblock copolymers of selected PHAs (PHB, PHBV, PHO) with atactic poly[(J ,5 )-3-hydroxybutyrate] (a-PHB) were obtained by using low-molecular weight macroinitiators derived from natural poly(3-hydro-jyalkanoates), which contain olefinic units and activated by 18-crown-6 ether carbojylic end groups. These new polymers are suitable for use as blend compatibilizers. ... 

Figure 11 Schematic molecular structures of (a) hydrogen- and (b) ionic- bonded LC polymers as well as (c) LC ionomers and (d) LC ionophoric copolymers, containing a crown-ether terminal group.

This approach has been extended to the synthesis of macrocyclic ethers (pseudo-crown ethers) incorporated as part of a macromolecular network (styrene-divinylbenzene copolymer) and results in polymers of high coordinating power for various ions (139). The combination of macrocyclic structures with polymer will allow, in the near future, the development of new catalysts containing specific binding properties together with effective catalytic behavior (348). 

Fig. 12.15 Structures of three different calix[4]pyrrole copolymers, namely the calix[4]pyrrole copolymer 24 reported by Akar et al. [42] the ditopic copolymer 25 containing a calix[4]pyrrole and a crown-5 ether [43], and the polystyrene polymer 26 bearing pendant calix[4]pyrroles of Aydogan [44]...

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