Investigation Into The Processing Parameters Of Solution Blowing

The nanofibers have several special properties like surface effect, small size effect, quantum size effectand tunnel effect of the macroscopic quantum as small size and high surface area to the volume ratio, whichcan be used in many fields such as life science, filter membrane, tissue engineering scaffolds and nano sensors.Electrospinning is a simple method for producing nanofibers. But the defects are low production and the lowprobability of industrialization. Solution blowing is a new method for making nanofibers, affecting the solutionor molten polymer by air force, which makes the polymer solidified into ultra-fine or nanofibers throughtensile deformation in particular spatial. High voltage electrostatic or charged collection devices areunnecessary. The solution range is wider, not limited to high dielectric constant solvent. It will not affect thepolymer which is voltage or heat sensitive. It has the potentiality of industrialization, but the lack of theoreticalresearch is restriction. We design two pieces of solution blowing equipment, one is vertical form equipmentand another is double groove equipment, study the effect of different process parameters to the diameter ofnanofiber. Preliminarily research the air filter applicant of solution blowing.In chapter one, we summarized the production and application of nanofiber, research status anddevelopment tendency of solution blowing and the filtration of fiber.In chapter two, produced nanofibers using the vertical form equipment with PEO/water solution underdifferent process parameters and properties of solution (including spinning distance, air pressure, injection rate,needle diameter and distance between slit and the needle)．And simulate the flow field of vertical formequipment using fluent software, analysis the velocity and turbulence intensity of center line of the flow field. In chapter three，one needle is used to produce nanofibers using the silt form equipment with the samesolution. Analyzed the change of diameter and the standard differential through orthogonal method withdifferent process parameters and properties of solution (including spinning distance, air pressure, injection rate,needle diameter and the needle projection length)．And we simulated the flow field of vertical form equipmentusing fluent software, analysis the velocity and turbulence intensity of center line of the flow field.In chapter four, produced nanofibers using the vertical solution blowing, compound the melt blownproducts with solution blowing products, make melt blown/solution blowing/melt blown material (MLMmaterial for short). Tested the filtration performance and pressure drop of MLM material with differentspinning time and distance. Charged the material, study the filtration performance, pressure drop and surfacecharge density with different time, distance and voltage.In chapter five, summarized the influence of vertical form equipment and double groove equipment withdifferent process parameters.Based on the research, it helped to reveal the influence of different process parameters to the morphologyof the fiber, airflow velocity and the turbulence intensity of center line. Also it has great theoretical andpractical value for designing and manufacturing machine of solution blowing.