A novel synthetic route has been developed to couple selectively a modified octa-peptide, that is able to gel at low temperature, to the prototypical thermoresponsive polymer poly(N-isopropylacrylamide) to give a bioconjugate that exhibits double thermoresponsiveness.

Summary:We have synthesised and characterised three sets of acryloyl(amino-acid)/ NIPAAm co-polymers. Three different co-monomers were synthesised and copolymerized with N-isopropylacrylamide (NIPAAm) by free radical polymerization in different molar ratios (12:1, 9:1, and 6:1). All series contain aliphatic spacers and are carboxylic terminated. The effect of co-monomer nature and content on the glass transition and the LCST transition in solution has been investigated. The main factor affecting the glass transition and the LCST of the polymer was found to be the side chain length of the co-monomer. The introduction of the co-monomer resulted in an overall increase in the polymer hydrophobicity which led to a decrease of both the polymer glass transition and the LCST transition observed in solution.

It was studied the possibility to obtain cermets with nickel on alumina basis, using conventional methods such as cold pressing and sintering. γ transitional alumina was employed as oxide elemental, due to its OH- groups which have a positive effect to the press, by decreasing the friction forces. There were investigated the Al2O3-Ni cermets in the range where the concentration of the ceramic material is preponderant. Oxide and metallic admixtures were mixed in the powdered blend in order to study their influence on the properties of the cermets. These were characterized by measuring sintering density, hardness, bending strength and fracture toughness. The values of the characteristics are comparable to those reported in literature for non-conventional energetic methods: the sintered density up to 98%TD; the Rockwell hardness up to 40HRC; the bending strength up to 352MPa and the fracture toughness up to 4MPam0.5, function of their composition. The fracture has a mixed character, it is fragile-ductile.

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