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In the articles's2) published recently, Buback et al. have presented data about the polymerization of ethylene initiated by thermal or photochemical method in a wide range of pressure (1600-2440 bar) and temperature (129-265°C). It was shown that the method of initiation has no effect on the molar mass, molar mass distribution and degree of long chain branching (A) of polyethylene (PE). Those structural parameters, however, are greatly influenced by pressure, temperature and ethylene conversion during the polymerization. The kinetics of polymerization was analysed on the basis of the classical theory of free-radical polymerization. Correlations of polymerization pressure and temperature with the structural characteristics of PE were presented.In spite of the fact that an approach of this kind is well established in the interpretation of the polymerization processes, some advances are necessary in the case of the high pressure polymerization of ethylene. It is known3) that pressure accelerates the polymerizations because it aligns the monomer molecules in a way which favours the chain propagation step. Compression causes the monomer molecules to lose some of their rotational and translational entropy, with the result that they have less to lose when they become built into the growing polymer chains. The acceleration of polymerization at high pressure is entirely due to the increase of activation entropy3).Since the density of ethylene in the polymerization conditions (0,4 -0,6 g/cm3) exceeds the density of loosely packed unoriented ethylene molecules (0,28 g/cm3), Hunter concluded that ethylene molecules under polymerization conditions are properly oriented and distorted4). It has recently been shown by us5) that during compression the ethylene molecules are organized in different supermolecular particles.This supermolecular organization of compressed ethylene, represented by the low ethylene entropy, has a decisive effect on the polymerization mechanism, the kinetics and the structure of PE6). As a rule, the same structure of PE should be expected if the entropy of ethylene is equal in different polymerization runs, even if the other polymerization conditions (pressure, temperature, type of initiation, etc.) are quite different ').In this cornmefits we want to explain how the data obtained by Buback et al. can be interpreted on the basis of the organization of monomer molecules, i.e. ethylene 0025-1 16X/85/$03.00

SYNOPSISSome new cellulosic materials, suitable for the adsorption of noble metal ions, were synthesized by chemical and electrochemical modification of cellulose. The polymerizable groups were introduced in cellulose with -80% yield of substitution by esterification with acryloyl chloride. The vinyl monomers (4-vinylpyridine, 1-vinylimidazole, l-vinyl-2-pyrrolidinone, and 9-vinylcarbazole) were readily grafted into cellulose acrylate via radical polymerization in acetonitrile. The grafted copolymers of cellulose with 4-vinylpyridine and 4-vinylimidazole were reacted with methyl iodide and the corresponding 1-methylpyridinium iodide (6) and 3-methylimidazolium iodide (7) copolymers of cellulose were obtained. Copolymers 6 and 7 were transformed into new polymeric regents, differing in anions (ClO;, CF&OO-, NO;, p-TsO-, BF;, PF,) by using a supporting electrolyte carrying the desired anions through the ion-exchange-electrochemical oxidation of the released iodide at a controlled anodic potential.

We find that nitrogen plasma treatment of micro/nanofibrillated cellulose films increases wettability of the surface by both liquid polar water and nonpolar hexadecane. The increased wetting effect is more pronounced in the case of polar liquid, favouring the use of plasma treated micro/nanofibrillated cellulose films as substrates for a range of inkjet printing including organic-based polar-solvent inks. The films were formed from aqueous suspensions of progressively enzymatic pretreated wood-free cellulose fibres, resulting in increased removal of amorphous species producing novel nanocellulose surfaces displaying increasing crystallinity. The mechanical properties of each film are shown to be highly dependent on the enzymatic pretreatment time. The change in surface chemistry arising from exposure to nitrogen plasma is revealed using X-ray photoelectron spectroscopy. That both polar and dispersive surface energy components become increased, as measured by contact angle, is also linked to an increase in surface roughness. The change in surface free energy is exemplified to favour the trapping of photovoltaic inks.

Post-combustion CO 2 capture (PCC) technology offers flexibility to treat the flue gas from both existing and new coal-fired power plants and can be applied to treat all or a portion of the flue gas. Solvent-based technologies are today the leading option for PCC from large coal-fired power plants as they have been applied in large-scale in other applications. Linde and BASF are working together to further improve a post-combustion capture technology incorporating BASF's novel aqueous amine-based process based on the results of the joint development of BASF, Linde and RWE at the PCC pilot plant in Niederaussem, Germany. This technology offers significant benefits compared to other solvent-based processes as it aims to reduce the regeneration energy requirements using novel solvents that are very stable under the coal-fired power plant feed gas conditions. BASF has developed the desired solvent based on the evaluation of a large number of candidates and long-term small pilot-scale testing has been performed on a lignite-fired flue gas. Linde has evaluated a number of options for capital cost reduction in large engineered systems for solvent-based PCC technology.Pilot-scale demonstration on a coal-fired power plant flue gas at a 1-1.5 MW e scale is currently planned under a project supported by DOE (project award DE-FE0007453). Mechanical completion of the pilot plant was achieved in July 2014 and the final commissioning activities are being completed to enable start-up of operations in late 2014. The pilot plant incorporates the capability to test a number of unique features of the Linde-BASF technology aimed at lowering the overall energy consumption as well as resulting in capital cost reduction.In this presentation, the details of the fabrication, construction and start-up of the pilot plant will be discussed. The pilot plant incorporates significant instrumentation and control features to enable automated and stable operation, and the ability to reliably