NANJING SUMINO&SINOMA TECHNOLOGY PTFE MEMBRANE EXPERT REVIEW MEETING

At 9 o'clock on the morning of December 24, 2020, under the leadership of a group of leaders, the technical team of Nanjing Sumino Precision and the experts and professors of Sinoma Technology Nanjing Fiberglass Research and Design Institute officially met at Sinoma Technology.

Participants included the project team leader, the director of Sinoma Science and Technology, Dean Liu, Professor Liu, Professor Chen of the Fiberglass Institute, and the relevant professional leaders of Nanjing University of Science and Technology.

The purpose of this meeting is to launch project equipment presentations on the related design, R&D and production of PTFE film production equipment, and to discuss relevant process and equipment parameters. The meeting was held smoothly, and representatives from all parties actively spoke and discussed. After four hours of the meeting, the two parties reached an agreement on the relevant equipment and technology and related improvements, and discussed at the next meeting.

Polytetrafluoroethylene (Poly tetra fluoroethylene, abbreviated as PTFE), commonly known as "Plastic King", is a high molecular polymer prepared by polymerizing tetrafluoroethylene as a monomer. White waxy, translucent, excellent heat and cold resistance, and can be used for a long time at -180～260oC. This material is resistant to acids, alkalis, and various organic solvents, and is almost insoluble in all solvents. At the same time, PTFE has the characteristics of high temperature resistance, and its friction coefficient is very low, so it can be used for lubrication and become an ideal coating for easy cleaning of the inner layer of water pipes.

Introduction and microstructure of PTFE membrane

PTFE film is a microporous film made of polytetrafluoroethylene as raw material, using a special process, calendering, extrusion, biaxial stretching and other methods. PTFE membranes can be divided into clothing membranes, air filtration membranes, and air purification membranes according to their uses. The PTFE membrane has a fibril-like microporous structure with a porosity of over 85%, 1.4 billion micropores per square centimeter, and a pore size range of 0.02μm-15m.

The main structure

1. The surface morphology of the PTFE microporous film is a spider web-like microporous structure. Pores are formed between the microfibers, and the arrangement direction of the microfibers is basically the same as the stretching direction; the junction of the fiber bundle is the node, which is formed by many microfibers entangled and connected.

2. PTFE membrane is an asymmetric membrane, and the micropore size of the front and back of the membrane is different.

3. The cross-sectional micropore size of the membrane is larger than the surface micropore size, and the vertical and horizontal micropore sizes are also different, and the longitudinal micropores are larger than the horizontal.

4. The cross-section of the membrane is a network structure. There are very complicated changes in the three-dimensional structure of the hole, such as network connection, hole inserting, and hole bending. There may be multiple micropores forming a channel, or there may be a micropore with Multiple channels are connected.

2. PTFE air filter membrane

Utilizing the unique node fibril property of PTFE microporous membrane, smooth surface, chemical resistance, air and water impermeability, large air permeability, flame retardant, high temperature resistance, strong acid and alkali resistance, non-toxic and other characteristics, it can be used for atmospheric dust removal , Air purification, etc. The product made of the membrane has high filtration efficiency, up to 99.99%, close to zero emissions; low running resistance, fast filtration speed; long service life, reusable, thereby reducing operating costs. Mainly used for flue gas filtration of various industrial furnaces such as chemical industry, steel, metallurgy, carbon black, power generation, cement, garbage incineration, etc. PTFE filter membrane, the pore size of the membrane can be controlled between 0.2-15μm, and the porosity can reach more than 85%.
3. PTFE air purification membrane

The air purification membrane is made of polytetrafluoroethylene, which is expanded and stretched to form a microporous membrane. This membrane is laminated on various fabrics and substrates with a special process to become a new filter material. The membrane has a small pore size (0.05～0.45μm), uniform distribution, and large porosity. While maintaining air circulation, it can filter all dust particles including bacteria to achieve the purpose of purification and ventilation. It is widely used in pharmaceutical, biochemical, Microelectronics and laboratory supplies and other fields.

Nanjing Sumino Precision Machinery Co., Ltd. is a high-tech enterprise integrating scientific research, production, and sales. It has always adhered to the business philosophy of integrity, equality, and customer benefits first. In order to better improve the quality of equipment, it has entered a more professional and standardized Production track. We have established independent R&D technologies for seven categories of equipment including plastic sheet materials, casting, biaxial stretching, non-woven non-woven meltblown fabrics, laminating film composites, renewable granulation environmental protection recycling systems and coating machine manufacturing systems. Center and production department. Provide a full set of professional technical solutions to meet the special needs of each customer.

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