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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]

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]

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]

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]

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]

3-Aminophthalic anhydride was synthesized in high purity by heterogeneous catalytic transfer hydrogenation of 3-nitrophthalic acid. The reduction was carried out in a one-pot reaction under microwave conditions, using 4-methyl-1-cyclohexene as a source of hydrogen, in short reaction times. By microwave-assisted polymerization of the resulting AB-type amino anhydride monomer in bulk, linear and cyclic polymers consisting of amic acid and imide units were formed. Copyright © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

We describe the molecular recognition of polymeric attached isomers meta-isopropylphenol and para-isopropylphenol, respectively, in a copolymer of N-isopropylacrylamide (NIPAAm) by use of randomly methylated β-cyclodextrin (RAMEB-CD). The acrylic monomers 4- and 3-isopropylphenylacrylate were synthesized and radically copolymerized with NIPAAm yielding the corresponding polymers. The supramolecular structures resulting from complexation with RAMEB-CD were characterized using dynamic light scattering, turbidity, NMR spectroscopy and isothermal titration. We found differences in binding constant, mean coil size and cloud point as a result of different complexations of the mentioned polymer-bound isomers with RAMEB-CD. Copyright © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Four hydrophobic amidine containing monomers N-(pyridin-2-yl)methacrylamide ( 3) , 5-(pyridin-2-ylamino)pentyl methacrylate ( 7), S-5-(isopropenylcarbonyloxy)pentyl-N,N-diphenylthiourea ( 9) and methyl-5-guanidino-2-methacrylamidopentanoate ( 12) were synthesized and copolymerized with a water soluble co-monomer N,N-dimethylacrylamide ( 13) or N-isopropylacrylamide ( 22). The second component was a copolymer containing methacrylic acid ( 19) and 13/22. By combination of these two components the formation of amidinium-carboxylate interactions was determined by dynamic light scattering (DLS), H-NMR spectroscopy and rheology measurements. [ABSTRACT FROM AUTHOR]

The in vitro enzyme-mediated polymerization of vinyl monomers is reviewed with a scope covering enzymatic polymerization of vitamin C functionalized vinyl monomers, styrene, derivatives of styrene, acrylates, and acrylamide in water and water-miscible cosolvents. Vitamin C functionalized polymers were synthesized via a two-step biocatalytic approach where vitamin C was first regioselectively coupled to vinyl monomers and then subsequently polymerized. The analysis of this enzymatic cascade approach to functionalized vinyl polymers showed that the vitamin C in polymeric form retained its antioxidant property. Kinetic and mechanistic studies revealed that a ternary system (horseradish peroxidase, H2O2, initiator β-diketone) was required for efficient polymerization and that the initiator controls the characteristics of the polymer. The main attributes of enzymatic approaches to vinyl polymerization when compared with more traditional synthetic approaches include facile ambient reaction environments of temperature and pressure, aqueous conditions, and direct control of selectivity to generate functionalized materials as described for the ascorbic acid modified polymers. [ABSTRACT FROM AUTHOR]

Polysaccharides are formed by repeated glycosylations between a sugar donor and a sugar acceptor. This chapter reviews the in vitro synthesis of polysaccharides by “enzymatic polymerization.” As catalyst, a hydrolase enzyme is used where the monomer was designed based on the concept of a “transition-state analog substrate” (TSAS), sugar fluoride monomers for the polycondensation, and sugar oxazoline monomers for the ring-opening polyaddition. Enzymatic polymerization enabled the first in vitro synthesis of natural polysaccharides such as cellulose, xylan, chitin, hyaluronan, and chondroitin, and also of unnatural polysaccharides such as a cellulose-xylan hybrid, a regularly methylated cellulose, and derivatives of hyaluronan and chondroitin. The polymerization mechanism is discussed here. Mutant enzymes were effective for polysaccharide synthesis, where only polycondensation of monomers was induced by suppressing the hydrolysis activity. The polymerization principle was extended to a stepwise synthesis of oligosaccharides. By using characteristics of the polymerization to produce a polysaccharide by a single step, in situ observations of the polymerization reaction by TEM, POM, SEM, and SANS revealed the formation of various high-order molecular structures from the polysaccharide molecules. [ABSTRACT FROM AUTHOR]

Novel bis(vinylcyclopropane)-based monomers with cholesteryl group and high molecular weight were prepared. The phase behaviour of the synthesized monomers was investigated. The obtained macromonomers showed a polymerisation shrinkage that was significantly lower compared to dimethacrylates used in dental composites. [ABSTRACT FROM AUTHOR]

Iron shows fast heat development under microwave (MW) irradiation. This property was used to start polymerization reactions on the surface of iron fibres. MW irradiation of metal fibres, which are located in a monomer solution consisting of methyl methacrylate, ethylene glycol dimethacrylate, N,N'-azoisobutyronitrile and toluene led to the formation of polymer on the metal fibre surface. After dissolving the covered iron component in hydrochloric acid, a channel-containing polymeric material was obtained. Scanning electron microscopy showed a smooth material with rough inner channels. These internal surface structures were caused by the rough surface of the metal fibres. [ABSTRACT FROM AUTHOR]

The homopolymerization of methylated-β-cyclodextrin (me-β-CD) host–guest compound of tert-butyl methacrylate (1a) is described. We investigated the free radical polymerization of the complexed monomer (1a) and of the free monomer (1) at ambient and high temperature. Poly(tert-butylmethacrylate) synthesized via the cyclodextrin mediated method exhibited number-average molecular weights ranging from 12,000–60,000 g/mol with polydispersities from 1.9–3.1. The polymerizations without cyclodextrin show significantly lower yields in comparison with the cyclodextrin mediated polymerizations. Here, the polymer obtained is colloidal dispersed. At ambient temperature (20°C) no polymerization occurs in the absence of cyclodextrin, whereas, under the same conditions, the homopolymerization of the complexed monomer (1a) leads to polymerization with yields around 75%. [ABSTRACT FROM AUTHOR]

Describes the synthesis and characterization of various cyclodextrins and their derivatives. Use of monomers and randomly methylated cyclodextrin for yielding water soluble host-guest complexes; Investigation of the radical polymerization of monomers; Utility of cuclodextrins in polymer chemistry.

Presents a process of preparing comb-like polymers bearing chalcone groups and non-covalently attached cyclodextrins in the side chains. Description of the synthesis and free radical polymerization of a methacrylamide monomer; Condensation of 4-N-methacryloyl-6-aminohexanoylamino- acetophenone, 1, with 4-nitrobenzaldehyde; Steps of the process following the condensation.