This work has two objectives in the investigation of polymer solution lower critical solution temperature (LCST): First, to develop a new instrument to monitor LCST onset during copolymer synthesis by coupling several thermostatted light scattering flow cells to the output stream of an ACOMP system (Automatic Continuous Online Monitoring of Polymerization reactions). Second, to use this to inve...

A range of amphiphilic statistical copolymers is synthesized where the hydrophilic component either methacrylic acid (MAA) or 2-(dimethylamino)ethyl methacrylate (DMAEMA) and hydrophobic comprises methyl, ethyl, butyl, hexyl, 2-ethylhexyl methacrylate, which provide a broad partition coefficients (log P). Small-angle X-ray scattering studies confirm that these self-assemble to form well-defined...

1 H-MAS NMR is shown to be a powerful and attractive technique for quantifying the comonomer content in ethene--alkene copolymers, as exemplified by a series of ethene--hexene copolymers. The main advantages of applying 1 H-MAS solid-state NMR are related to; a) the very short experimental sampling time, on the order of a few minutes b) the bypass of sample preparation, as compared to traditi...

The functionalization and cross-linking of polyethylene is synthetically challenging, commonly relying on highly optimized radical based postpolymerization strategies. To address these difficulties, a norbornene monomer containing Meldrum's acid is shown to be effectively copolymerized with polyethylene using a nickel α-iminocarbaxamidato complex, providing high-melting, semicrystalline polymer...

Current polymer terminology only describes very simple copolymer structures such as block, graft, alternating periodic, or statistical copolymers. This restricted vocabulary implies that copolymers exhibit either segregated (i.e., block and graft), regular (i.e., alternating and periodic), or uncontrolled (i.e., statistical or random) comonomer sequence distributions. This standard classificati...

The structural characterization of copolymers by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) remains a challenging task, since their random comonomer distribution creates very complicated mass spectra. In this study, a high-resolution TOF mass spectrometer with a spiral ion trajectory was applied to the structural and compositional characterization...

Several kinds of biodegradable hydrogels were prepared via in situ photopolymerization of Pluronic F127/poly(ε-caprolactone) macromer and acrylic acid (AA) comonomer in aqueous medium. The swelling kinetics measurements showed that the resultant hydrogels exhibited both thermoand pH-sensitive behaviors, and that this stimuli-responsiveness underwent a fast reversible process. With increasing pH...

Polystyrene (PS) is a major commodity polymer widely used in various applications ranging from packaging to insulation thanks its low cost, high stiffness, and transparency as well relatively softening temperature. Similarly all polymers prepared by radical polymerization, PS constituted of C–C backbone thus not degradable. To confer degradability such materials, the copolymerization vinyl mono...

in this study, the slurry polymerization of ethylene over ticl4/mgcl2/alet3 was obtained. firstly, to obtain the optimum value of [al]/[ti], the effect of [al]/[ti] on polymerization rate and catalyst yield was studied. also, the effect of catalyst content on yielding, crystallization, melting point and density of product were obtained. to determine the order of reaction, the monomer pressure w...

Long-chain branches and narrow molecular weight distribution is a novel structure combination in polyethene, which has only been possible to achieve with single-center catalysis. Long-chain branches, even at very low concentrations, have a strong effect on the polymer melt behavior and, thereby, the processing properties. This work deals with ethene polymerization using group IV metallocene cat...