Grafting of Chitosan: Structural, Thermal and Antimicrobial Properties

In this study, some new chitosan materials were synthesized by the grafting of chitosan with the monomers such as 1-vinylimidazole (VIM), methacrylamide (MAm) and 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS). First of all, chitosan methacrylate was prepared by esterification of primary -OH group with methacryloyl chloride a 25.13% yield by mole. The monomers were grafted into chitosan methacrylate via free radical polymerization using 2,2and#39;-Azobisisobutyronitrile as an initiator in N,N-dimethylformamide. The graft copolymers were characterized by FT-IR spectra and elemental analysis. Thermal stabilities of the graft copolymers were determined by TGA (thermo gravimetric analysis) method. The synthesized chitosan methacrylate and its graft copolymers were tested for their antimicrobial activity against bacteria and yeast.

Characterization and Synthesis of This Comb Type Copolymer with Styrene Using A Macromonomer Containing Polyethylmethacrylate

In this study, firstly 7-hydroxy-4-chloromethyl coumarin (CMHC) was synthesized from reaction of ethyl 4-chloroacetoasetate with resorcinol. Then, the poly(ethyl methacrylate) coumarin end grouped having hydroxyl (CEMA) was prepared by ethyl methacrylate with using (CMHC) as initiator by atom transfer radical polymerization (ATRP) method. A macromonomer (CMEMA) was synthesized from reaction of methacryloyl chloride and poly(EMA) ended coumarin having OH group (CEMA). Molecular brush of P(CMEMA-comb-%16St) was synthesized by reaction of macromonomer CMEMA and styrene by free radical polymerization method (SRP). The structures of the prepared macromonomer and molecular brush were characterized by FT-IR and 1H-NMR techniques. The thermal behavior of P(CMEMA-comb-%St) has been investigated by TGA, and the glass transition temperatures have been measured on DSC. The average molecular weights and polydispersity were determined by GPC. The dielectric behavior of P(CMEMA-comb-%16St) was investigated as a function of temperature and frequency. The intrinsic viscosity [] of P(CMEMA-comb-%16St) was determinated.

Fire and mechanical properties of a novel free-radically cured phenolic resin based on a methacrylate-functional novolac and of its blends with an unsaturated polyester resin

A novel free-radically curable phenolic novolac resin bearing methacrylate functional groups has been synthesized by reaction of the novolac with methacryloyl chloride.

Synthesis of Crosslinker Containing Sulfone Group and its Crosslinking with Styrene

A new crosslinker containing sulfone group was synthesized by polymerization of 4,4’-dihydroxydiphenyl-sulphone and methacryloyl chloride. Using this kind of crosslinker, the crosslinked polystyrene beads were prepared by suspension polymerization and UV-light polymerization, respectively. The synthesized crosslinker and crosslinked polystyrene beads were characterized by nuclear magnetic resonance spectra and fourier transform infrared spectroscopy. The effect of crosslinker amount on sulfonation rate of beads was studied. Polystyrene beads made by suspension polymerization possess higher sulfonation rate when the crosslinker amount is lower than 6%. When the content of crosslinker is higher than 6%, the reaction still can be carried out by UV-light polymerization, but the coagulation occurred during suspension polymerization because of the extremely high polarity of crosslinker.

Influence of cyclodextrin on the UCST- and LCST-behavior of poly(2-methacrylamido-caprolactam)-co-(N,N-dimethylacrylamide)

The monomer 2-methacrylamido-caprolactam (4) was synthesized from methacryloyl chloride (3) and racemic α-amino-ε-caprolactam (2). Copolymerization of 4 with N,N-dimethylacrylamide (5) was carried out by a free-radical mechanism using 2,2’-azobis(2-methylpropionitrile) (AIBN) as an initiator. The new copolymers show a lower critical solution temperature (LCST) in water and an upper critical solution temperature (UCST) in ethanol, 1-propanol, and 1-butanol. The solubility properties of the copolymers can be influenced significantly by the addition of randomly methylated β-cyclodextrin (CD). The complexation of the copolymers with CD, was confirmed by the use of ROESY-NMR-spectroscopy.

Novel Insensitive Energetic Nitrogen-rich Polymers Based on Tetrazoles

Nitrogen-rich polymers were synthesized by radical polymerization using the reaction of 5- aminotetrazole with methacryloyl chloride and acryloyl chloride, respectively. The nitrogen content of poly(methacrylamidotetrazole) and poly(acrylamidotetrazole), as well as the energetic character of these compounds was increased by nitration of the amido moiety. The products remained however insensitive and had a very good thermal stability. All substances were characterized by using vibrational spectroscopy (IR), mass spectrometry, elemental analysis, as well as multinuclear NMR spectroscopy. Additionally, the impact and friction sensitivities were determined by BAM standards, and also the sensitivity against electrostatic discharge was studied. The energetic properties were investigated by bomb-calorimetric measurements and calculations with the EXPLO5 software, and the thermal stability was investigated by differential scanning calorimetry. All compounds are thermally highly stable materials. The high stability of the polymers towards impact and friction and the good energetic character makes these polymers promising candidates for applications as environmentally friendly nitrogen-rich polymers

Synthesis of Graft Copolymer by Using Acrylamide and Methacryloyl Chloride Guar Gum and its Adsorption Behavior to Metal Ions

a graft copolymer has been synthesized by reaction of acrylamide (AM) with methacryloyl chloride guar gum (MAG). The reaction condition was optimized, and the graft copolymer was characterized by FTIR and Scanning electron microscopy (SEM). Moreover the absorption behavior of the graft copolymer to metal ions at different conditions was studied.

Synthesis of a Flame Retardant Containing Nitrogen-Phosphor and its Application on Silk Fabric

In this paper, a flame retardant methacryloyl ethyl diethyl phosphoric amide (PN) containing nitrogen-phosphor for textiles was synthesized from phosphorus trichloride, absolute ethylalcohol, carbon tetrachloride, monoethanol amine, methacryloyl chloride. PN oil-in-water emulsion was grafted onto silk fabric by Atom Transfer Radical Polymerization (ATRP) method. The grafting technological parameters were investigated. The flame retardancy property of the treated silk fabric was indicated by LOI value, char length, after flame and after glow time.