PLASTIC SHEETING: GENERAL TERMINOLOGY
Gloss :
The films surface reflection of light. The degree of sheen of the surface.
Haze :
The degree of cloudiness of the film. Indicates how clearly an object can be seen through the film.
Opaque :
Film that inhibits light transmission. The opposite of transparent.
Tint :
Tiny voids in the film, enabling water, air, etc. to pass through the film.
Translucent :
A film that permits the transmission of light. Clear, transparent.
PLASTIC SHEETING FILM PROPERTIES
Orientation :
Alignment of the crystalline structure in film in both the machine and transverse directions.
Shrink :
The ability of film to conform to an object when reheated. A result of controlled orientation.
Impact Strength :
The ability of a film to withstand shock loading, blunt puncturing, etc.
Tensile Yield :
The pulling stress required to deform a given film specimen.
Tensile Break :
The pulling stress required to break a given film specimen.
Elongation :
A measure of how much a film can stretch over a given load profile.
Coefficient of Friction :
The ratio of a frictional gravitational force to the perpendicular force of the two surfaces in contact.
Treat: A method of altering a polyolefin surface to render it receptive to inks, adhesives, etc.
Water Vapor Transmission Rate :
Rate at which water vapor permeates a plastic film at a specified temperature and relative humidity.
Oxygen Transmission Rate :
Rate at which oxygen permeates a plastic film at a specified temperature and relative humidity
Surface Resistivity :
Measures the electrical resistance of the surface of the plastic.
ADDITIVES
Antiblock :
A silica or DE compound added to film that roughens the surface to prevent blocking.
Antistat: A compound added to film that dissipates the accumulation of static electricity.
Slip: A fatty acid amide added to film to reduce surface friction.
UltravioletAbsorber :
A compound designed to selectively absorb pass through UV rays.
UltraVioletInhibitor :
A compound designed to selectively scavenge destructive free radicals set free by UV rays
UltravioletBlocker :
A compound designed to selectively block pass through UV rays.
Vapor Corrosion Inhibitor :
A compound added to film for the prevention of oxidation or corrosion of packaged parts.
RESIN TYPES & TERMS
Low Density Polyethylene :
An ethylene based thermoplastic polymer with a nominal density of .910-.925.
Medium Density Polyethylene :
An ethylene based thermoplastic polymer with a nominal density of .926-.939.
High Density Polyethylene :
An ethylene based thermoplastic polymer with a nominal density of .940-.965.
Linear Low Density Polyethylene :
A low density, low pressure polymer resulting from the introduction of comonomers to control density.
Butene LLDPE :
Lowest grade of LLDPE, this polymer still outperforms LDPE in strength and sealabilty.
Hexene LLDPE :
Next level of LLDPE, this polymer has improved tear and impact over butene.
Super Hexene LLDPE :
Highest level of LLDPE, has excellent tear strength and dart impact, with optics improving.
Octene LLDPE :
Highest level of LLDPE, has excellent tear strength, very good dart impact and better optics.
Metallocene LLDPE :
LLDPE with unsurpassed dart impact, very high clarity, good tear strength and very good hot tack.
Very Low Density Polyethylene :
A low pressure copolymer with outstanding impact strength, stretch and low temperature sealabilty.
Ethylene Vinyl Acetate :
LDPE that has been copolymerized with ethylene vinyl acetate to enhance strength and sealability.
Thermoplastic :
Polymeric material capable of being repeatedly softened by heat and hardened by cooling.
APPLICATIONS :
Polyethylene Geo membranes are extensively used for prevention of liquid contamination. They act as perfect liners to prevent contaminations from entering groundwater sources, as well as prevent seepage loss, and hence, help in potable water conservation.
The conveyance of irrigation water in canal system often give way to water seepage and ultimately leads to loss of irrigation water. 70% of irrigation water is lost in a completely unlined canal.
The life span of roads depends on various factors like the soil being prevented from sub-grade movement. This is achieved by using LDPE sheet and LDPE plastic sheet placed in such a way that the aggregate is permanently separated from finer soils below. This prevents the sub-grade to enter into the aggregate and at the same time, improves the underground drainage of roadways.
Other Applications:
- Agricultural purposes
- Lining of canals, distributaries, reservoirs, ponds
- Lining of Industrial effluent plants, dunnage
- Tunnels, trenches
- Packaging
- Water-proofing for terrace gardens
- Emergency shelter houses during natural calamities
- Fumigation covers, cover Tops, tarpaulins, cap covers
- Aprons & runways at airport
- For covering of food grains, fertilizers, cotton, chemicals, cement & constructions
- Concrete roads and bridges and other such uses
- Sports stadiums
- Salt pans