Composite film (with security)

"Lamination Film is a microporous membrane or ultrafiltration membrane for the support layer, in its surface covered with a thickness of only 0.1 ~ 0.25μm dense homogeneous membrane as a barrier layer composed of separation membrane. So that the amount of material through a great increase. The material of the composite film includes any possible combination of materials, such as coating a metal oxide on a ceramic film or coating an aromatic polyamide film on a polysulfone microporous membrane, both of which are made of nonwoven Reinforced to support the pressure resistance of the microporous membrane, while the hollow fiber membrane is not required.     The preparation method is divided into four categories: (1) laminating method, first preparing a thin dense homogeneous membrane, and then laminated on the microporous support film; (2) dip coating method, the polymer solution dip in the microporous (3) a plasma vapor deposition method, using a plasma glow to allow the microporous support to be supported on the microporous membrane, and then subjecting the active monomer or prepolymer solution to a microporous film, (4) interfacial polymerization, on the surface of the microporous support membrane, with the active monomer interface polymerization.     Composite film is mainly used for reverse osmosis, gas separation, pervaporation and other separation process.     A film of a surface active layer (a dense separation layer) having a separation function and a porous layer having a supporting action was prepared by using two different film materials.     Composite film is in the film on one or both sides of the geotextile paste to form a composite geomembrane. The form of a cloth a film, two cloth a film. Width of 4-6m, weight 200-1500g / square meter, tensile, tear, broken and other physical and mechanical properties of high index, the product has high strength, good extension performance, deformation modulus, Anti-corrosion, anti-aging, anti-seepage performance and so on. To meet the water conservancy, municipal, construction, transportation, subway, tunnel, construction in the seepage, isolation, reinforcement, crack reinforcement and other civil engineering needs. Because of its choice of polymer materials and the production process to add anti-aging agent, it can be used in non-conventional temperature environment. Commonly used in the dam, drainage ditch of the anti-seepage treatment, as well as waste field anti-fouling treatment. Design material editing According    to the nature of the project, category, application site, the use of conditions, design requirements to select the appropriate type and specifications.    According to the engineering design of the water pressure requirements, as well as exposure, buried pressure, climate, life and other application conditions, to determine the thickness of geomembrane.     According to the actual size of the project, the area, the construction conditions, the construction capacity, the minimum seams at construction principle, to determine the geomembrane width and length.     When the base for the concrete structure, it is appropriate to choose directly on the cement base directly on the filament [1]     highway used in anti-seepage treatment, the central partition with the bottom of the general use of a cloth a film 200-300g / m Processing Method Editing    1. Drying method The method is a method in which the adhesive is applied to the surface of the substrate by a laminating machine, and the heating roller is pressed against the other film.     2. Wet compound method The water-soluble adhesive (gelatin, starch), water-dispersible adhesive (vinyl acetate latex, etc.) is coated on the surface of the substrate in a wet state with other materials, and then pressed and dried by roll Methods.     3. Extrusion method This is the most commonly used method of composite processing, with extruder PP, PE, EVA (ethylene - vinyl acetate copolymer) ion resin and other extrusion film, coated in the processing agent (Polyethyleneimine, polyurethane resin, etc.) on a variety of films to be compounded, and then by cooling, curing.     4. Hot-melt composite method The base resin is blended with a coating agent such as rosin, xylene resin, styrene resin and paraffin wax, and is coated on the surface of the film, the paper surface and the aluminum foil, and is immediately compounded A method of cooling on other substrates.     5. Co-extrusion method The method is two or three extruder at the same time forming two layers can be more than the film, T die method and blow molding method, can be a variety of composite, can produce ultra-thin Shaped film.     4 PE / PE, PVC / PE, NY / PVDC, PE / PVDC, PP / PVDC and so on. Three-layer composite such as BOPP / PE / OPP, PET / PVDC / PE, PET / PT / PE, PT / AL / PE, wax / paper / PE and so on. Four-layer composite such as PT / PE / BOPP / PE, PVDC / PT / PVDC / PE, paper / aluminum foil / paper / PE and so on. Five-layer composite such as PVDC / PT / PE / AL / PE and so on. Six-layer composite such as PE / paper / PE / AL / PE / PE and so on. Problem Solving EditProblem Reason:     1. Substrate thickness is not uniform, thin thickness difference is too large.     2. Substrate deflection, resulting in composite film wrinkles, and with the accumulation of skew, the degree of wrinkles will be a corresponding increase. If the substrate is susceptible to humidity by the film material (such as nylon film), and the occurrence of moisture absorption, in the extrusion process is prone to fold.     4. Tension set and improper control, the various parts of the tension is not coordinated, do not match.     5. Composite pressure is not set properly.     6. The axis between the silicone rubber press roll and the cooling steel roll is not parallel.     7. Guide roller surface is not clean, sticky foreign body, or guide roller surface is not smooth, there are pits, strokes, bumps and other phenomena. Solution:     1. Replace the substrate to ensure uniform substrate thickness.     2. Adjust the position of the substrate, in the transmission process does not occur skew.     3. The substrate is subjected to a preheating drying process or a substrate which does not undergo moisture absorption.     4. Adjust the unwinding and winding tension, so that each part of the tension to adapt and match each other.     5. Adjust the pressure of the compound roll to the appropriate size according to the actual situation.     6. Adjust the relative position between the silicone rubber press roller and the cooling steel roll so that both are kept parallel.     7. Clean the surface of the guide roller and replace the damaged guide roller to ensure that the guide roller surface is smooth, smooth and clean. Cause of failure:     1. Extruder temperature is set improperly, especially the die and resin temperature is too low, resulting in poor resin plastic, so that the phenomenon of shark skin smear or fish-like spot marks.     2. Resin contains water, affecting the plasticization of the resin.     3. Resin mixed into the melt index or other different density of resin, so that resin is not good plastic or plastic is not complete.     4. When the resin is replaced, the cartridge is not thoroughly cleaned and the remaining resin or impurities remaining in the cartridge have an adverse effect on the resin plasticization. Solution:     1. The extrusion temperature and the temperature of the extruder are adjusted to an appropriate value to ensure that the resin is well cured.     2. The resin is stirred and dried to remove the moisture contained therein so that the resin can be sufficiently plasticized.     3. Replace the melt index and the appropriate density of the resin.     4. Thoroughly clean the barrel, remove impurities and so on. Odor failure:     1. Extruder temperature or resin temperature is too high, resulting in resin decomposition, resulting in odor.     2. The air gap is too large, the resin is oxidized too much, the surface produces a variety of oxygen-containing groups, so that the composite membrane odor.     3. The resin itself has a smell, with its extrusion composite film will have a complex odor.     4. The use of high boiling point in the primer, not volatile solvents, resulting in some solvent residue, resulting in composite film after the smell. Solution:     1. Appropriate to reduce the extrusion temperature, to prevent the decomposition of resin.     2. Adjust the size of the air gap to the appropriate value.     3. The use of low-odor resin for extrusion composite.     4. Improve the drying temperature of the drying tunnel, increase the amount of blow to ensure that the solvent is fully dry. Deformation failure:     1. Tension settings and improper control, the tension between the ministries is not suited.     2. Bake temperature setting is too high.     3. The composite pressure is too large to cause the composite film to be stretched.     4. Cooling steel roll surface temperature is too high, the composite film cooling effect is poor, easy to produce roller stretching phenomenon. Solution:     1. Check and determine the tensile phenomenon occurs in the equipment which paragraph, according to the specific circumstances of the tension value of the paragraph to adjust to the appropriate, with the other sections of the tension to match the size.     2. Properly reduce the temperature of the bake.     3. Appropriate to reduce the composite pressure.     4. Reduce and control the surface temperature of the cooling steel roll, so that the distribution of uniform, good cooling effect. Surface failure:     1. Cooling steel roll surface temperature is too high, the cooling effect of molten resin is poor, affecting the composite film cooling, curing and forming, resulting in molten resin sticking to the surface of the cooling steel roller.     2. When the composite resin temperature is too high.     3. The winding tension is too small to peel off the composite film from the surface of the cooling roll. Solution:     1. The temperature of the cooling water and the surface temperature of the cooling steel roll are appropriately lowered to improve the cooling effect.     2. According to the specific circumstances appropriate to reduce the resin temperature, adjust the size of the air gap, the molten resin temperature control in the appropriate range. 3. The winding tension is appropriately increased, and the composite film is peeled off from the surface of the cooling steel roll. Poor transparency:     1. Extruder extrusion temperature is too low, resulting in resin plastic poor, the transparency of the composite film have a certain impact.     2. Cooling steel roll surface temperature is too high, the cooling effect is too bad, so that composite membrane transparency greatly reduced.     3. The transparency of the substrate itself is not good. Solution:     1. According to the characteristics of resin and the actual production conditions to set and control the corresponding extrusion temperature, to ensure good resin plastic, which is to improve the transparency of composite membrane one of the prerequisites.     2. The temperature of the cooling water and the surface temperature of the cooling steel roll are appropriately lowered. In general, the temperature of the cooling water is controlled to 20c or less, and the surface temperature of the cooling steel roll is controlled to 60c or less.     3. Replace the substrate with good transparency."