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A new surface modification followed by calculation of Hansen solubility parameters to predict dispersability of cellulose nanocrystals in LDPE is presented.

Composite films were sprayed from mixtures of water soluble hydroxypropyl methylcellulose (HPMC) and either nanofibrillated cellulose (NFC) or cellulose nanocrystals (CNC). Fiber diameter was similar for both nanocelluloses but fiber length was several µm for NFC and about 200 nm for CNC. Films were characterized for morphology, swelling, mass loss and transport properties. NFC-HPMC films swelled less than CNC-HPMC films; with a HPMC content of 20wt% NFC-HPMC and CNC-HPMC films presented swelling of 7 and 75 g/g, respectively. The swelling strongly influenced water transport across the films, with slower transport for CNC-based materials compared to NFC-based materials. The properties of NFCbased films were comparable to previous results using microfibrillated cellulose (MFC) with heterogeneous structural content and fiber lengths of ~10 µm. The findings have implications for using nanocellulose to modulate material properties in wet-state applications, with effects being in strong contrast when using as a hardening filler in dry materials.

Synthesis of bis-4,5-diazafluoren-9-one silver(I) nitrate I, (dafone = 4,5-diazafluoren-9-one) and low temperature X-ray single crystal structure of [Ag(4,5-diazafluoren-9-one) 2 NO 3 ], crystal form 1, and a re-determination of [Ag(4,5-diazafluoren-9-one) 2 ]NO 3 ·H 2 O, crystal form 2 are presented.Crystal form 1 has a distorted trigonal planar coordination geometry around Ag(I) with an N-Ag-N bond angle of 123.45(7)°. Crystal form 2 has a perfect linear coordination around Ag, with N-Ag-N 180.0°. Compound I was characterized by 1 H-NMR, biological activity and ESI-MS in DMSO at room temperature. The biological activity was determined against 6 different resistant clinical isolates; two Gram-positive (Staphylococcus aureus and Streptococcus pyogenes) and four Gramnegative (Pseudomonas aeruginosa, Klebsiella pneumoniae, Proteus mirabilis, and Salmonella sp.) in comparison with 15 known antibiotics used in the treatment of diabetic foot infections.Compound I showed broad spectrum activity against all the test organisms. Proteus mirabilis, Staphylococcus aureus and Proteus mirabilis were the most sensitive clinical isolates (MIC = 4, 6 and 4 µg/ml, respectively). Three different hydrogels containing I or Ag 2 SO 4 were prepared and the antimicrobial activity against Pseudomonas aeruginosa (ATCC 15442) compared, showing more or less equal activity on a weight basis, but I seems to have a significant better performance per silver ion. The Ag(I) complex also binds more effectively to calf thymus DNA than the dafone ligand itself. reaction was performed in an acetonitrile/water mixture at room temperature, only crystals of [Ag(dafone) 2 ]NO 3 ·H 2 O, 2 were formed. But when an ethanol/water mixture was used with heating, prismatic crystals of [Ag(dafone) 2 NO 3 ], 1 and needles of [Ag(dafone) 2 ]NO 3 ·H 2 O, 2 were collected from the same batch. Synthesis of silver loaded hydrogelsTo vary degrees of cross linking of the hydrogels different molecular weights of dimethacrylated PEG (polyethylene glycol) monomers (PEGDMA) were used and three gels containing different ratios of PEGDMA8k, PEGDMA20k, TEGDA (triethylene glycol diacrylate) and PEGDA700 were prepared with water as a solvent.Silver sulphate (2% and 6% by weight) and 1 (2%) with 1% photoinitiator was added and the mixtures cured with a UV Lamp giving nine different gels. Notable differences in appearance of the produced gels were noted: while the gels with 1 were white/transparent much like a nonsilver containing gel, the gels with Ag 2 SO 4 were severely discoloured, see Figure 1. Figure 1. Dimethacrylated PEG gels with left: 2% 1, right: 2% Ag 2 SO 4Crystal Structures The two structures are strikingly different, we will therefore first present each structure and in conjunction make appropriate comments, and thereafter we will bring up the points that are of general interest in dafone coordination chemistry.Crystallographic data and refinement parameters for crystal forms 1 and 2 are listed in Table 1, Accepted manuscript New Journal of Chemistry, 35,[640][641]...