The melt blown method is made by the polymer directly into the net, the screw extruder extruded polymer melt through high-speed high-temperature air jet or other means (such as centrifugal force, electrostatic force), the melt flow by extreme stretching And the formation of very fine short fiber, and then gathered into the net into a mesh or into the network curtains on the formation of fiber, and finally by self-adhesive to be reinforced and made of non-woven fabrics.
The specific process is to polymer chips through the screw extruder to melt, after filtration from the spinneret nozzle hole in the extrusion, in the high-speed hot air jet blowing, by drawing, forming a very fine Short fibers, these staple fibers are adsorbed and condensed into a net curtain. As the filament has not been cooled, so after the cohesion into the network can still maintain a high temperature, through the fiber adhesion between each other, so that the network can be reinforced to form a meltblown cloth. Can be further reinforced according to the need of hot-rolled bonding method.
At present, most of the raw materials used in the meltblowing process are polypropylene, polyester or polyamide can be used. In order to make the melt fine flow can be better in the process of hot air blowing, drawing the melt index of raw materials May be higher. Different melt index of raw materials used in the spinning temperature, blowing air flow and the speed of the corresponding changes to ensure that the yarn is fully drafted to improve the quality and performance of the fiber.
Melt spray method can currently be used in the raw material of polypropylene, polypropylene, polyethylene, polystyrene and polyphenols, the most commonly used is polypropylene. Because the method uses high pressure hot air draft, it is necessary to use the raw materials to control the temperature is low, good flow performance of raw materials, that is, the use of higher melt index polymer is conducive to improving production and reduce energy consumption. The melt index (MFI) of polypropylene is generally above 18.
Polymer feed - melt extrusion - fiber formation - fiber cooling - web - reinforcement into cloth.
The complete set of equipment for producing meltblown nonwovens is composed of main parts, heating system, lubrication system, hydraulic system, cooling system and electrical control system. The host is the core of the complete set of equipment, including the feeding system, screw extruder, filter, spinning components, spinning die, receiving network system, winding mechanism.
Meltblown production line
Spunbond technology uses a similar fiber grade polymer, which is extruded through a spinneret in a linear or ring arrangement through a spinneret, and the polymer stream is subjected to air cooling and mechanical stretching The desired filament diameter is obtained, and the diameter of the continuous filament is generally 15 to 20 m, and then the filaments are collected on the conveyor belt and are subjected to a final bonding step (needling or thermal bonding) to obtain a higher strength Fiber web.
Spunbond processing technology can be summarized as the following two points:
1, the polymer slices into a cloth
2, in a complete, continuous production line to obtain all the spunbond network.
The performance and use of fabrics obtained with different processes are different.
As the meltblown adhesive fabric fiber diameter is smaller, better filter performance (can filter smaller diameter material), with ultra-fine filter effect, which is the biggest feature of meltblown non-woven fabrics, it is often used for breathable Retaining material. More than half of all fabrics made by meltblowing are used in medical, pharmaceutical and industrial filtration materials. Absorbent materials, adsorbent materials, wipes and packaging materials are the second largest consumer areas.