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Poly(acrylic acid)s ( PAAs) with curable methacrylamide moieties as well as bisacrylamide crosslinkers are described as components for well-defined hydrogels with increased hydrolytic resistance. PAAs with tethered curing moieties of different alkyl spacer lengths (−( CH2) n−, n = 2, 3, 6 or 8) were prepared via copolymerization of one-sided methacrylated diamines with protected acrylic acid, followed by polymer-analogous methacrylation and deprotection. Bisacrylamide crosslinkers were synthesized by acrylation of diamines with different cores and N-substitutes like allyl, cyclopropyl or propyl groups. Both components were subsequently combined for the formation of novel amide based hydrogels. Network densities of the obtained gels were elucidated by rheokinetic investigations. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Two novel cyclodextrin-modified anthraquinone dyes were synthesized and investigated for their complexation behaviour and formation of superstructures. Therefore, 1-fluoro-4- N-(propargylamino)anthraquinone and 1,4-bis(propargyloxy)anthraquinone were prepared via nucleophilic aromatic displacement and subsequently covalently 'click-coupled' in a copper(I)-catalysed azide-alkyne cycloaddition with β-cyclodextrin monoazide. Both the propargyl-modified precursor and the click-coupled anthraquinone dyes were evaluated as hosts and guests, respectively, in β-cyclodextrin interactions. The anthraquinone dye bearing two cyclodextrins, 1,4-bis((1- β-cyclodextrin-1 H-1,2,3-triazol-5-yl)methoxy)anthraquinone, enables the reversible formation of supramolecular crosslinked poly[( N, N-dimethyl acrylamide)- co-( N-(ferrocenoylmethyl)acrylamide)] ( 11), whereas the monofunctionalized compound 1-fluoro-4-(((1- β-cyclodextrin-1 H-1,2,3-triazol-5-yl)methyl)amino)anthraquinone can be supramolecularly linked to 11 resulting in coloured polymers. These features of β-cyclodextrin-linked anthraquinone dyes can be verified with either 1H 1H NMR rotating frame nuclear Overhauser effect spectroscopy or the naked eye. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The oxidative coupling of 4- tert-butylphenol ( 1), 2,6-di- tert-butyl- p-cresol ( 11) and 4-cyanophenol ( 10) in the presence of iron salen catalysts (salen = N, N′-bis(salicylidine)ethylenediamine) and the influence of amine additives on the conversion of 1 were investigated. Furthermore, the activity of the iron complexes was correlated with the substituents at the 5,5′-positions of the salen ligands. Mechanistically conclusions based on dimer formation in the reaction between 10 and 11 are presented. In the second part of the study the obtained hydrophobic poly(4- tert-butylphenol) was modified with Jeffamine® M-600, M-1000 or M-2070 to give amphiphilic copolymers (18a-c). The amphiphilic copolymers were characterized via size-exclusion chromatography and dynamic light scattering. The concentration dependence of the cloud point appearance in water of amphiphilic copolymer 18c was analysed via turbidity measurements. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Hydroxyalkylation of N-vinylcaprolactam (NVCL) in α-position via ring-opening reaction of propylene oxide and ε-caprolactone, respectively, yields in precursors for multifunctional NVCL derivatives. Homo- and copolymers of hydroxyfunctionalized NVCL derivatives, synthesized by free radical mechanism, are further investigated regarding their thermoresponsive behavior. Esterification of hydroxypropylated NVCL derivative with methacrylic anhydride is carried out yielding a versatile bifunctional cross-linker. Networks are obtained either via free radical polymerization of the cross-linker or anionic polymerization of only the methacrylic function and subsequent polymer analogous cross-linking of the vinylic side groups. The rheological behavior during and after curing is investigated by oscillatory rheology. Furthermore, N-vinylcaprolactam anion is used as an initiator for the anionic ring-opening polymerization of ε-caprolactone. Copolymerization of poly( ε-caprolactone) macromonomer with NVCL yields graft copolymers. A polymerizable thermotropic liquid crystalline (LC) derivative is prepared by coupling cholesteryl chloroformate to NVCL. The thermal behavior of LC derivative is investigated by differential scanning calorimetry and polarized light microscopy. [ABSTRACT FROM AUTHOR]

The synthesis of the 4-(dialkylamino)pyridine derivative 3-(4-(pyridin-4-yl)piperazin-1-yl)propyl methacrylate and its copolymerization with n-butyl methacrylate are presented. The catalytic activity was evaluated in the acylation of tert-butanol with acetic anhydride yielding tert-butyl acetate. It is observed that the activity of polymer-attached 4-(dimethylamino)pyridine analogues correlates remarkably well with the chemical shift of the β-pyridyl protons. Differences in catalytic efficiency result from distinct electronic densities of the pyridine ring, while embedding the catalytically active moiety into a polymeric structure has nearly no deleterious effect on the performance. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Two enantiomers of isobornyl methacrylate ( iBMA) were prepared by reducing (1 R,4 R)-(+)-camphor and (1 S,4 S)-(−)-camphor followed by simple methacrylation reaction. The iBMA enantiomers were incorporated into hydrophilic polymer networks by free radical polymerization with N, N-dimethylacrylamide and diethylene glycol dimethacrylate at different molar ratios. The influence of α-cyclodextrin ( α-CD) and randomly methylated β-cyclodextrin (r β-CD), and thereby enantioselectivity, on the swelling behaviour of the enantiomeric networks in water and alcoholic solutions was examined. An increase of swelling was observed on addition of α-CD and r β-CD. While r β-CD showed a greater influence on the swelling itself, only α-CD was able to achieve a minor differentiation between the polymer networks by their enantiomeric components and therefore a chiral recognition of the iBMA moieties. These results were validated using rheological measurements. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

A new series of crosslinkable dimethacrylates containing thioether and phosphonic acid were synthesized. The structures of the different synthesized crosslinkable agents based on oleic acid, cinnamic acid, acrylated glycerol 1,3-dimethacrylate and a chalcone derivative were established by electrospray ionization, DSC, NMR and Fourier transform infrared spectroscopy. In order to prove the accessability of the double bonds on network formation, the radical curing of these compounds with N, N-dimethylacrylamide as comonomer was examined. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Alkylation of N-vinylpyrrolidone using lithium diisopropylamide and bis(2-bromoethyl) ether was carried out to obtain 3-(2-(2-bromoethoxy)ethyl)-1-vinyl-2-pyrrolidone (2). The derivative 2 represents a versatile starting molecule for further modification via nucleophilic displacement yielding, for example, the bicyclic 2-vinyl-8-oxa-2-azaspiro[4.5]decan-1-one (4) or the ammonium salt 3-diethoxy-N,N'-((dimethylbenzyl)ammonium bromide)-1-vinyl-2-pyrrolidone (10). Via free radical polymerization of 4 and 10, the corresponding homopolymers were obtained. Copolymerization of 4 and 10 with N,N'-diethylacrylamide yielded water-soluble materials. The thermosensitive solubility of copolymers poly[(2-vinyl-8-oxa-2- azaspiro[4.5]decan-1-one)-co-(N,N'-diethylacrylamide)] and poly[(3-diethoxy-N,N'-((dimethylbenzyl)ammonium bromide)-1- vinyl-2-pyrrolidone)-co-(N-vinylpyrrolidone)] in water was investigated. [ABSTRACT FROM AUTHOR]

The synthesis and (co-)polymerization of 2-(4-(pyridin-4-yl)piperazine-1-carboxamido)ethyl methacrylate ( 1) was carried out yielding the catalytically active poly(methacryloyl-4-(dialkylamino)pyridine) derivatives ( 2), ( 3) and ( 4). In addition, the tertiary-amine-containing terpolymers poly(methacryloyl-4-(dialkylamino)pyridine- co-butyl methacrylate- co-2-(dimethylamino)ethyl methacrylate) ( 5a − 5c) were prepared. Furthermore, kinetic studies of the acylation of tert-butanol with acetic anhydride to form tert-butyl acetate were conducted to evaluate the catalytic activity of the (co-)polymers. It turned out that homopolymer 2 exhibited the best performance, followed by the terpolymers 5a − 5c. The influence of the neighboring groups in the catalytic cycle is discussed. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

N-Benzyl-3-methylenepyrrolidin-2-one ( 3) was synthesized and homopolymerized under free radical conditions. The configurational microstructure of poly( N-benzyl-3-methylenepyrrolidin-2-one) ( 4) is isotactic with a minor tendency to syndiotacticity. Monomer 3 was also homopolymerized in water in the presence of methylated β-cyclodextrin. The glass transition temperature of 4 of 124 °C was compared with the lower value of 61 °C of the ring-opened analogue poly( N-benzyl- N-ethylacrylamide). © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

A polydimethylsiloxane macromonomer was synthesized via anionic ring-opening polymerization of hexamethylcyclotrisiloxane using N-vinylcaprolactam anion as initiator and trimethylsilyl chloride as terminating agent. The polydimethylsiloxane macromonomer was copolymerized with N-vinylcaprolactam in different molar ratios via a free radical mechanism. The new class of graft copolymers thus obtained shows cloud points in water because of an excess of N-vinylcaprolactam units in the polymer chain. These cloud points can be shifted using randomly methylated β-cyclodextrin as complexing agent. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

A new polymerizable 1,1′-bi-2-naphthol derivative for polymer-supported catalytic asymmetric synthesis is presented. The synthesis is conducted within a single reaction step, which is a major advantage over other approaches presented in the literature. The ligand-bearing polymer is prepared through copolymerization with N-isopropylacrylamide. Preliminary experiments on the utility in catalytic asymmetric alkylation reactions reveal the accessibility and activity of the polymer-attached catalysts. The stereoselectivity of the reaction is found to be somewhat lower than for reactions performed in the presence of free 1,1′-bi-2-naphthol, and thus requires further optimization. The enantiomeric excess of the reaction products was determined via 1H NMR spectroscopy after chiral derivatization with ( R)- α-methylbenzyl isocyanate. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

α-Aminocaprolactam is reacted with the isocyanate function of 2-isocyanatoethyl (meth)acrylate to yield monomers 2-[3-(2-oxoazepin-3-yl)ureido]ethyl (meth)acrylate. These hydrogen bond-forming monomers crystallize easily in macroscopic bunches of needles. Subsequently, homopolymers and copolymers of the monomers with N, N-dimethylacrylamide are synthesized radically. The homopolymers have spherical structures and are semi-crystalline showing large amorphous domains. Polymeric solutions of the homopolymers in water-ethanol have an upper critical solution temperature. In contrast, the solutions of the copolymers in water have a lower critical solution temperature. If copolymerized in concentrated solution, the copolymers show gelation after treatment with excess water. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Amongst functional macromolecules, the combination of polymers and dyes is a research field of great potential with regard to high-performance materials. Accordingly, colored polymers have become increasingly important as materials for miscellaneous technical applications in recent years while also being a major part of everyday life. For instance, dye-containing polymers are nowadays widely applied in medicine, painting industries, analytics and gas separation processes. Since these applications are obviously connected to the dye's nature, which is incorporated into the corresponding polymers, the affinity of certain polymers to dyes is exploited in wastewater work-ups after (textile) dyeing procedures. In this review, we wish to point out the great importance of dye-containing polymers, with a comprehensive scope and a focus on azo, triphenylmethane, indigoid, perylene and anthraquinone dyes. Since a large number of synthetic approaches towards the preparation of such materials can be found in the literature, an elaborated overview of different preparation techniques is given as well. [ABSTRACT FROM AUTHOR]

The glucose oxidase and glucose mediated formation of amphipilic copolymers of N-(ferrocenoylmethyl)acrylamide (NFMA) and N,N-diethylacrylamide (DEA) in aqueous cyclodextrin solution is presented. Thereby, NFMA is not only a comonomer but also part of the redox initiation system. The obtained copolymers contain NFMA units between 1 and 10 mol%. The molecular masses of the copolymers are dependent on the ferrocene content, whereupon molecular weights between 38 000 and 71 000 g mol−1 are achieved. [ABSTRACT FROM AUTHOR]

Monomers containing benzaldehyde units were synthesized by esterification of 4-hydroxybenzaldehyde and 4-(2-hydroxyethoxy)benzaldehyde with methacryloyl chloride. These monomers were copolymerized free radically with N-isopropylacrylamide using 2,2′-azobis(2-methylpropionitrile) as an initiator. The monomers and copolymers, respectively, were modified with acetone in an organocatalytic aldol reaction in the presence of l-proline to induce stereogenic centers. The aldol condensates were characterized by their optical rotatory power. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

A crosslinking agent of thioether containing a phosphonic acid, (3-((11-((1,3-bis(meth­acryloyl­oxy)propan-2-yl)oxy)-11-oxoundecyl)thio)-propyl)phosphonic acid ( 6), is synthesized. The crosslinking agent is characterized by electrospray ionization (ESI), NMR, and Fourier transform infrared (FTIR) spectroscopy. After the copolymerization with N,N'-dimethyl­acrylamide, the influence of the metal ions Ca2+, Fe3+, and La3+ on the swelling behavior of these disc-shaped samples is examined. The rheological behavior of unswollen and swollen crosslinked copolymers is also investigated with respect to the added metal ions. [ABSTRACT FROM AUTHOR]

The preparation of AB2 monomers via thiol-ene click reaction from six- and seven-membered unsaturated lactones is described. The hydroxyl-functionalized valerolactone was prepared by use of Michael thiol-ene-addition reaction starting from 2-mercaptoethanol and 3-methylenetetrahydro- 2H-pyran-2-on. The hydroxyl-functionalized caprolactone was prepared radically from 2-mercaptoethanol and 7-allyloxepan-2-one. Both AB2 monomers were polymerized via ring opening in the presence of tin( II)-2-ethylhexanoate (Sn(Oct)2) as a catalyst yielding the hyperbranched polyesters. The new hyperbranched polyesters were analyzed by 13C NMR spectra to determine the degree of branching. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

N-vinylcaprolactam (NVCL) is modified via alkylation at the α-position. The α-substituents are ethyl (3-ethyl-1-vinylcaprolactam), dodecyl (3-dodecyl-1-vinylcaprolactam), octadecyl (3-octadecyl-1-vinylcaprolactam), 1-propanol (3-(3-hydro­xy-propyl)-1-vinylcaprolactam), and PEG3 bromide (3-PEG3-bromide-1-vinylcaprolactam). These monomers are homo- and copolymerized with N-(4-methylphenyl)­maleimide by the free radical mechanism. The structures of the obtained polymers are characterized by means of 1H NMR and IR spectroscopy, gel permeation chromatography (GPC), and by use of differential scanning calorimetry (DSC) ( Tg). [ABSTRACT FROM AUTHOR]

The redox switchable formation of very well-defined supramolecular graft polymers in aqueous solution driven by host-guest interactions between ferrocene (Fc) and cyclodextrin (CD) is presented. The Fc-containing acrylic backbone copolymer (PDMA-stat-Fc) is prepared via reversible addition-fragmentation chain transfer (RAFT) copolymerization of N, N-dimethyl­acrylamide (DMA) and the novel monomer N-(ferrocenoylmethyl)acrylamide (NFMA). Via the RAFT process, copolymers containing variable Fc ratios (5-10 mol%) are prepared, affording polymers of molecular masses of close to 11 000 g mol−1 and molar mass dispersities ( Đ) of 1.2. The β-cyclodextrin (β-CD) containing building block is synthesized via RAFT-polymerization, too, in order to afford a polymer with well-defined molecular mass and low dispersity ( [ABSTRACT FROM AUTHOR]

Thiol‐ene photopolymerizations combine the unique features of step‐growth reactions and photoinitiated polymerizations, so that they experience a growing interest for applications such as coatings or dental restoratives. Most studies have making use of a relatively flexible ester and the hydrolytically labile derivative pentaerythritoltetra(3‐mercaptopropionate) (PETMP) as the thiol component in common. In this study, the performance of hydrolytically stable 1,3,5‐tris(3‐mercaptopropyl)‐1,3,5‐triazine‐2,4,6‐trione (4a), 1,3,5‐tris(2‐methyl‐3‐mercapto‐propyl)‐1,3,5‐triazine‐2,4,6‐trione (4b), and oligomers thereof in thiol‐ene photopolymerizations is investigated. The oligomers are prepared via thiol‐Michael or thiol‐isocyanate additions by using 4a and suitable diacrylates or diisocyanates containing a rigid core structure. Compared with PETMP, the thiol derivative 4a shows better flexural strength and modulus of elasticity in thiol‐ene photopolymerizations with 1,3,5‐triallyl‐1,3,5‐triazine‐2,4,6‐trione (TATATO) as the‐ene derivative. This phenomenon becomes especially evident after storage in water at 37 °C for 24 h. Furthermore, the performance regarding the flexural strength, the Young's modulus of elasticity, the polymerization shrinkage stress of 4a, and the polyadducts thereof in dental filling composites is evaluated and discussed. [ABSTRACT FROM AUTHOR]

Bifunctional aminoalkyldimethylpropylammonium salts ( N-(3-aminopropyl)- N, N-dimethylpentylammonium chloride, N-(3-aminopropyl)- N, N-dimethyloctylammonium chloride, N-(3-aminopropyl)- N, N-dimethyldecylammonium chloride, N-(3-aminopropyl)- N, N-dimethyldodecylammonium chloride) are synthesized and their structure-dependent antibacterial effect against Gram-negative Escherichia coli and Gram-positive Lactococcus lactis is investigated. To this end, resins prepared from bisphenol A diglycidyl ether (2,2-bis[4-(glycidyloxy)phenyl]propane) and diethylenetriamine (2,2′-diaminodiethylamine) as matrix and the bifunctional aminoalkyldimethylpropylammonium salts in a ratio of 6 mol% compared to epoxy components are used. A dependence of antibacterial effect on alkyl chain length of the quaternary ammonium compounds is observed for both species. Furthermore, resins with N-(3-aminopropyl)- N, N-dimethyldecylammonium chloride in varying concentrations up to 16 mol% for both organisms show a concentration-dependent antibacterial effect of the quaternary ammonium salt. The antibacterial materials are characterized by differential scanning calorimetry, infrared spectroscopy and rheological studies. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

1-Vinyl-2-(methoxymethyl)imidazole ( 6), 1-vinyl-2-(ethoxymethyl)imidazole ( 7), 1-vinyl-2-(prop­oxy­methyl)imidazole ( 8), and 1-vinyl-2-(butoxymethyl)imidazole ( 9) are synthesized through the etherification of 1-vinyl-2-(hydroxymethylimidazole) ( 1) with corresponding alkyl halides ( 2-5). Corresponding homopolymers ( 10-13) are synthesized via free radical polymerization and investigated concerning their temperature-dependent solubility in water. The homopolymer 11 shows a lower critical solution temperature (LCST) behavior with a cloud point of 23 °C. Through copolymerization of 7 with N-vinylimidazole ( 14), the cloud point is varied up to 42 °C. [ABSTRACT FROM AUTHOR]

The control of reactivity of several bis( N-glycidylsulfonamides) by aromatic substituents is presented. Therefore, disulfonamides with electron-withdrawing or electron-donating aryl moieties and a linear, branched, or oxygen-substituted spacer are synthesized and further N-alkylated with epichlorohydrin. Their curing times with N, N-dimethyl aminopropyl amine in comparison with standard bisphenol A diglycidyl ether are measured by oscillatory rheology. A dependence of curing time with the Hammett σ-value is found. [ABSTRACT FROM AUTHOR]

Unsaturated polyesters are synthesized via ring-opening copolymerization of α-methylene-δ-valerolactone and δ-valerolactone. These polyesters 4a-c are mixed with ethyl methacrylate (EMA), 2-hydroxyethyl methacrylate (HEMA), and α-methylene-δ-valerolactone (α-MVL), respectively. Then, crosslinking is carried out by free radical polymerization initiated by an azo-initiator. A second glass transition is found with incorporation of HEMA and α-MVL. These findings indicate the formation of phase-separated polyester blocks crosslinked with the poly(meth)-acrylic-segments, respectively poly(α-methylene-δ-valerolactone) segments. [ABSTRACT FROM AUTHOR]

An N-vinylimidazole-based monomer carrying an adamantyl group, (1-vinyl-2-yl)methyl­adamantan-1-ylcarbamate ( 3), is synthesized. The terpolymerization with N-vinylimidazole ( 4) and 1-vinyl-2-(hydroxymethyl)imidazole ( 2) yields terpolymers ( 5a-b) with high upper critical solution temperature (UCST)-type transitions in water. The solubility can be influenced by the addition of various amounts of randomly methylated β-cyclodextrin (RAMEB-CD). It is found that supramolecular host/guest interaction clearly controls the solution behavior. [ABSTRACT FROM AUTHOR]

Randomly methylated β-cyclodextrin (me-β-CD) is used to include the hydrophobic monomer N-(4-methylphenyl)maleimide (MPM) ( 1) yielding the corresponding water-soluble host-guest structure 1a. Free-radical copolymerization of 1a with N-vinylpyrrolidone (NVP) ( 2) is performed and the reactivity ratios r1 and r2 are determined: 0.24 ± 0.03 ( r2) and 1.10 ± 0.05 ( r1a). This indicates a preferred incorporation of complexed maleimide into the copolymer chain. In contrast to that, the copolymerization of the uncomplexed monomers 1 and 2 is carried out using organic solvent (DMF/H2O) showing reactivity ratios corresponding to nearly alternating copolymerization ( r2 = 0.09 ± 0.02; r1 = 0.34 ± 0.03). [ABSTRACT FROM AUTHOR]

Intelligente Hydrogele: Rohlinge aus Adamantyl ‐ modifizierten, vernetzten hydrophilen Polymeren wurden in Wasser und wässriger Cyclodextrin(CD) ‐ Lösung bei verschiedenen Temperaturen gequollen. CD erhöhte hierbei den Quellungsgrad drastisch. Darüber hinaus wurden Polymerstreifen im 5 ‐ cm ‐ Maßstab oberhalb ihrer Glasübergangstemperatur verdrillt und in Wasser und CD ‐ Lösung gequollen. Ein Formgedächtniseffekt in wässriger CD ‐ Lösung konnte beobachtet werden. [ABSTRACT FROM AUTHOR]

The modulation of the cloud point of aqueous poly( N, N-diethylacrylamide) solutions via the formation of supramolecular cyclodextrin complexes with hydrophobic end groups, namely adamantyl, tert-butyl phenyl and azobenzene, synthesized via RAFT polymerization is described. The dependence of the apparent cloud points after cyclodextrin complexation is investigated with respect to the type and quantity of the guest end group, the polymer chain length and the cyclodextrin/end group ratio. Furthermore, the effect is reversed via the addition of guest molecules or via biocompatible enzymatic degradation of the cyclodextrins entire. [ABSTRACT FROM AUTHOR]

The copolymerization parameters of N-(isopropyl)acrylamide ( 1) and N-(2-hydroxy-5-(1-(4-hydroxyphenyl)-3-oxo-1,3-dihydroisobenzofuran-1-yl)benzyl)acrylamide ( 2) are determined. For both monomers, the homoaddition proceeds slightly faster than the heteroaddition step; however, the polymer formation occurs in a statistic fashion. Copolymers of different compositions are prepared and the cloud points are determined. Thereby, a significant influence of the concentration of monomer 2 and the pH value is found. For the first time, the complexation of polymer attached phenolphthalein by β-cyclodextrins is shown. Furthermore, it is possible to achieve a decomplexation by the addition of suitable guest molecules. Both procedures can be followed with the naked eye. [ABSTRACT FROM AUTHOR]

A novel graft copolymer is synthesized from commercially available poly(vinyl alcohol) using ring-opening polymerization. For the polymerization reaction of novel brush-like poly(vinyl alcohol)- graft-poly(ϵ-caprolactone- co-(3-/7-(prop-2-ynyl)oxepan-2-one) 5 Sn(Oct)2 is used as a catalyst. The formation of the graft copolymer is confirmed by 1H NMR, 13C NMR, and Fourier transform infrared (FTIR) spectroscopy. Furthermore, the modification of the novel synthesized graft copolymer via a 'click' reaction to implement adamantane groups is described. The success of the 'click' reaction is proven by 1H NMR spectroscopy and visualized by decomplexation of cyclodextrin with included phenolphthalein. [ABSTRACT FROM AUTHOR]

1-Vinyl-2-(hydroxymethyl)imidazole ( 2) is synthesized by a procedure described in the literature. Corresponding copolymers with upper critical solution temperature (UCST)-type transitions in water and high-glass transition temperatures ( Tg) are prepared by free radical copolymerization with N-vinylimidazole ( 1). Depending on the copolymer composition, the cloud point can be varied between 19 and 41 °C. As the copolymer composition is identical with the monomer feed ratio, the cloud point can be easily tuned in the desired range. Furthermore, a distinctive pH-dependence and salt effect can be observed. [ABSTRACT FROM AUTHOR]

ABSTRACT The design and synthesis of a new hydrophobic monomer, that is, 4-( tert-butyl)phenyl 6-acrylamidohexanoate (TBP-AA-HO) and its ability to form supramolecular host/guest complexes with β-cyclodextrin (CD) is described. The aqueous CD-mediated reversible addition fragmentation chain transfer (RAFT) polymerization affords molecular masses up to 8600 g mol−1 with polydispersities between 1.2 and 1.4. The surprisingly low molecular weights for higher monomer/chain transfer agent (CTA) ratios are investigated by comparing results obtained from free radical and RAFT radical polymerization in aqueous and organic media. The results indicate a steric hindrance caused by attached CD molecules on the growing polymer chain leading to stagnation of the polymerization process due to a restricted accessibility of the reactive chain end. This hypothesis is supported by matrix-assisted laser desorption/ionization time of flight mass spectrometry. Furthermore, the CD-mediated synthesis of amphiphilic diblock copolymers in variable aqueous media is described. Hydrophilic poly( N, N-dimethylacrylamide) macro-CTAs with different molecular weights are used to polymerize TBP-AA-HO at 50 °C. The diblock copolymers are analyzed by 1H-nuclear magnetic resonance spectroscopy and size exclusion chromatography. The results confirm the polymer structure and reveal similar limitations of chain growth as observed for the CD-mediated homopolymerization with a limit of 7000 g mol−1 for efficient chain extension. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2504-2517 [ABSTRACT FROM AUTHOR]

ABSTRACT In this article, we report the noncovalent linkage of terminal substituted oligo(dimethylsiloxanes) bearing cyclodextrins (CD) as host endgroups and adamantan or ferrocene, respectively, as guest endgroups. Structural characterization was performed by 1H NMR-, IR-, and mass spectroscopy. Electron microscopy studies show significant differences in the surface structure of the individual derivatives. In addition, the ferrocene-terminated di-and poly(dimethylsiloxanes) are distinguished by a red-ox activity and reversibility, which also makes the complexes between the ferrocene- and CD functionalized siloxanes switchable via electrochemical stimuli. The evidence for a successful complexation of the end groups, and thus the successful supramolecular formation of the siloxane strands, was even performed by shift of the protons in the 1H NMR spectra. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2472-2482 [ABSTRACT FROM AUTHOR]