Overview of
EVA Plastics :
The ethylene-vinyl acetate copolymer is abbreviated as EVA, and the content of vinyl acetate (VA) is generally 5% to 40%. Compared with polyethylene, EVA is widely used in foaming shoes due to the introduction of vinyl acetate monomer in the molecular chain, which reduces high crystallinity, improves flexibility, impact resistance, filler compatibility and heat sealing performance. Materials, functional shed film, packaging film, hot melt adhesive, wire and cable and toys.
Characteristics of EVA plastic:
When the content of vinyl acetate in EVA is less than 20%, it can be used as a plastic at this time. EVA has good low temperature resistance, and its thermal decomposition temperature is low, about 230 °C. With the increase of molecular weight, the softening point of EVA rises, the workability and the gloss of the surface of plastic parts decrease, but the strength increases and the impact The toughness and environmental stress cracking resistance are improved. The chemical resistance and oil resistance of EVA are slightly worse than that of PE and PVC, and the change is more obvious with the increase of vinyl acetate content.
EVA has better performance than PE, mainly in terms of elasticity, flexibility, gloss, gas permeability, etc. In addition, its environmental stress crack resistance is improved, and the capacity of the filler is increased, and more reinforcing fillers can be added. Methods to avoid or reduce the degradation of EVA mechanical properties compared to PE. EVA can also be modified to obtain new applications. The modification can be mainly considered from two aspects: one is to use EVA as the backbone of other monomer grafting; the other is to partially hydrolyze EVA.
EVA plastic characteristics: It is widely used in foaming shoe materials, functional shed film, packaging mold, hot melt adhesive, wire and cable and toys.
1. EVA with a vinyl acetate content below 5%, its main products are film, wire and cable, LDPE modifier, adhesive, etc.;
2. The EVA product with a vinyl acetate content of 5%-10% is an elastic film;
3. EVA with a vinyl acetate content of 20-28%, mainly used for hot melt adhesives and coated products;
EVA is a copolymer of LLDPE (linear low density polyethylene) and acetic acid (VA).
EVA plastic properties:
EVA resin has good flexibility, rubber-like elasticity, can still have good flexibility at -50 ° C, good transparency and surface gloss, good chemical stability, good anti-aging and ozone resistance, no toxicity. It has good blending property with filler, and has good coloring and molding processability.
Process characteristics of EVA plastic particles:
As a kind of amorphous plastic, EVA plastic particles are non-toxic, and the density is lighter than water. The light value is 0.95g/cm3. The product has good fluidity, softness, lightness, good elasticity, low mechanical strength and easy processing. The surface gloss is poor. The product has a large shrinkage rate of 2%, and EVA plastic particles can also be used as a carrier for the color masterbatch.
Process characteristics of EVA plastic particles: EVA has a low processing temperature, generally 160-200 degrees Celsius, and the temperature range is wide, but the temperature of the mold is 20-45 degrees Celsius. The EVA plastic particles should be 65 before processing. Dry in an environment of Celsius.
When the EVA is processed and produced, the material temperature and mold temperature are not too high, otherwise the surface of the product will be rough and not smooth. Since the EVA plastic product is easy to stick to the front mold, it is preferably fixed at the cold hole of the main passage of the nozzle to prevent sticking. When the temperature at which EVA plastic particles are processed exceeds 250 degrees Celsius, the product itself is prone to decomposition. Therefore, the processing conditions of EVA plastic particles should be controlled under the external conditions of "low temperature, medium pressure and medium speed".
The dangers of EVA plastics:
Powder and air can form an explosive mixture. When a certain concentration is reached, it will explode in the event of Mars. Decomposition by heating produces flammable gas. Hazardous combustion products: carbon monoxide, carbon dioxide. Fire-fighting methods: Firefighters must wear gas masks, wear full-body fire-fighting suits, and put them on the wind. Extinguishing media: water spray, foam, dry powder, carbon dioxide, sand.
Storage Precautions: Store in a cool, ventilated warehouse. Keep away from fire and heat. It should be stored separately from oxidants and alkalis, and should not be mixed. Equipped with the appropriate variety and quantity of fire equipment. The storage area should be provided with suitable materials to contain spills.
WATERPROOFING ROLL MATERIAL
High
polymer Waterproof Roll Material series is our company take its advantage of
engaged in high polymer materials research, production for many years, combines
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asphalt self-adhesive waterproof sheet are widely used in the major waterproof
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Application
Various underground caves, tunnels, subways, bridges, basements, water conservancy dams, landfills, sewage treatment pond, municipal construction and other waterproofing anti-seepage projects.
Composite
high polymer waterproofing roll material series
NCL
high polymer self-adhesive film waterproofing roll material (non asphaltic
base)( with isolation membrane, with reaction sand)
High
polymer self-adhesive rubber asphalt waterproofing roll material
High
polymer self-adhesive back-lining rubber asphalt waterproofing roll material
Tunnel
dedicated composite waterproofing roll material ( NCL
high polymer self-adhesive film waterproofing roll material
specification
Width:2m Thickness: 1.2mm,1.5mm,2.0mm
Length:
20-30m (Can be customized according to user needs)
executive standard
GB/T 23457-2009 GB/T 23260-2009
Contact
Waterproof Rolls
Waterproof Rolls,Hdpe Waterproofing Membrane,Waterproof Rolling Material,Drainage Waterproof Roll
Shandong Tianhai New Materials Engineering Co., Ltd , https://www.chinatinhy.com