Search results for " Materiali"
showing 10 items of 710 documents
Solidification of Polypropylene Under Processing Conditions – Relevance of Cooling Rate, Pressure and Molecular Parameters
2012
Il concetto di "no-flow temperature" e il problema della solidificazione in flusso durante lo stadio di riempimento nel processo di stampaggio ad ini…
2012
Durante la fase di riempimento del processo di stampaggio ad iniezione, il flusso del materiale polimerico può fermarsi a causa della sua elevata viscosità, nonostante non sia avvenuta la solidificazione tramite transizione vetrosa o cristallizzazione. La no-flow temperature (NFT) è un parametro che rappresenta la "temperatura di solidificazione reologica" di un polimero, ed è utilizzata in molti software di simulazione del processo di stampaggio ad iniezione. L'estrapolazione della viscosità a basse temperature tramite modelli reologici può introdurre errori considerevoli nelle simulazioni, poichè le misure di viscosità sono usualmente effettuate ad alte temperature: in tal modo, i modelli…
CHARACTERIZATION OF HYDROPHOBIC POLYMERIC MEMBRANES FOR MEMBRANE DISTILLATION PROCESS
2010
Hydrophobic microporous membranes are utilized in membrane distillation (MD) processes, e.g. seawater desalination at moderate temperatures. The vapour permeability of commercial hydrophobic membranes with different pore sizes (0.2-1 micron) was characterized through a simple apparatus designed-on-purpose. A cylindrical vessel had a face closed by the membrane and the other connected to a thin graduate tube. The water level variation in the tube is recorded and related to the vapour flux across the membrane. Measurements were taken in the temperature range 20-80°C. A fan tangential to membrane surface was employed to maintain a constant driving force for vapour transport. Vapour flux did no…
Tubular scaffold for vascular tissue engineering application
2010
A critical obstacle in tissue engineering is the inability to maintain large masses of living cells upon transfer from the in vitro culture conditions into the host in vivo. Capillaries, and the vascular system, are required to supply essential nutrients, including oxygen, remove waste products and provide a biochemical communication “highway”. Another goal in this research field is the possibility to tune the biodegradability of the scaffold. After implantation, the scaffold has to be gradually replaced by cells and extra cellular matrix and it is crucial that this replacement takes place with an appropriate dynamics. A premature degradation, in fact, could lead to a collapse of the struct…
Comparison of the solidification of a commercial PBT-PET blend with the behaviour of the constituents
2009
PLLA scaffolds based on thermally induced phase separation: morphology, cell seeding and proliferation
2009
Thermal expansion of Glass fibre reinforced (GRF) thermoplastics: influence of the nature of the polymer matrix and of the fibre content
2009
PLLA biodegradable scaffolds for Vascular Tissue Engineering (VTE) applications via dip drawing and Diffusion Induced Phase Separation (DIPS)
2009
Physical and biological properties of electrospun poly(d,l‐lactide)/nanoclay and poly(d,l‐lactide)/nanosilica nanofibrous scaffold for bone tissue en…
2021
Abstract Electrospun scaffolds exhibiting high physical performances with the ability to support cell attachment and proliferation are attracting more and more scientific interest for tissue engineering applications. The inclusion of inorganic nanoparticles such as nanosilica and nanoclay into electrospun biopolymeric matrices can meet these challenging requirements. The silica and clay incorporation into polymeric nanofibers has been reported to enhance and improve the mechanical properties as well as the osteogenic properties of the scaffolds. In this work, for the first time, the physical and biological properties of polylactic acid (PLA) electrospun mats filled with different concentrat…
Poly lactic acid based scaffolds for vascular tissue engineering
2012
A critical obstacle encountered by tissue engineering is the inability to maintain large masses of living cells upon transfer from the in vitro culture conditions to host in vivo. Capillaries, and the vascular system, are required to supply essential nutrients, including oxygen, remove waste products and provide a biochemical communication "highway". The successful use of tissue-engineered constructs is currently limited to thin or avascular tissues, such as skin or cartilage, for which post-implantation neovascularisation from the host is sufficient to meet the demand for oxygen and nutrients. To succeed in the application of tissue engineering for bigger tissues, such as bone or muscle, t…