Pet film - what is it? description, types, properties, application

Processing

Thanks to the development of technologies for recycling plastic materials, it has become possible to significantly reduce the cost of PET film production. This process includes the bulkhead and crushing of the used lavsan packaging. After that, the crushed material goes through a series of cycles of cleaning from additives and washing, it is dried and goes through the stage of unloading. The resulting flakes go directly to production or are granulated. If the recycled plastic has been cleaned properly, then it can be used without any restrictions.

But at the same time, even the most substandard recyclable materials from polymer can be used to create packaging.

Summarizing the above, it can be noted that today PET-based film products have become an indispensable technical product that is widely used in production workshops for various purposes. Despite the wide selection of analogs made from other polymeric materials, the lavsan film wins in the niche of packaging containers due to a unique combination of performance characteristics. Ease of use and durability are combined with the environmental friendliness of the material - it is this factor that allows it to be widely used for the needs of the food industry.

What is the difference between APET, PET-E, PET-G and BOPET films, see below.

Raw material base

The film is made from a thermoplastic polymer in the form of polyethylene terephthalate, which is characterized by increased strength, transparency and plasticity. Depending on the particular manufacturing process, the product can also be imparted with improved chemical resistance properties and even the ability to withstand extreme temperatures. For example, PET blanks can withstand -40 to 75 ° C on average.

At the stage of PET film production, the polymer is used in the form of synthetic fibers. Roughly speaking, this is a plastic mass like plasticine, from which any (texture) material can be obtained by extrusion under pressure. The product is literally squeezed out of a special apparatus, after which it is cooled and, if necessary, forwarded to additional molding procedures. At the same stage, various fillers, dyes and other additives can be added to the composition of the future film product, which provide the same improving effect on individual qualities.

What it is?

Among a wide selection of polymer packaging materials, PET (polyethylene terephthalate) film is in great demand. In terms of its physical and operational characteristics, it resembles plexiglass and polycarbonate, but with higher performance parameters. Features of the material may vary depending on the use of certain additives. The unique characteristics of mylar film are combined with an affordable cost and the ability to recycle used products. All this leads to a consistently high demand for such films in a wide variety of industries.

They can play the role of semi-finished products for subsequent technical processing or be used as completely finished products, in the latter case they will have to undergo molding (electrical insulating products, textile fibers), extrusion (thin film) or high pressure molding (packaging for products in liquid form).

Thanks to the introduction of complex additives, it is possible to achieve the required degree of mattness of the finished product and the required color, to correct the parameters of hardness and elasticity.It is possible to change the properties of the finished product by successively replacing the stages of cooling and heating between the initially amorphous state and the crystalline state that emerged during heating to 80 degrees or more.

Varieties of film

The assortment is very large. Films differ in thickness, transparency and color brightness. They are matte, metallized, with a twist effect, holographic. This is not the whole list of lavsan films.

For example, a film with a twist effect has the ability to “remember” its shape. Usually candies and tablets are wrapped in such packaging.

The shrink film shrinks as temperatures rise, tightly wraps around the product, creating a vacuum effect. Outwardly, it is absolutely transparent, shines well, with high strength, protects the product from negative factors.

The skin film has a hot-melt surface. Differs in high optical and mechanical properties, prevents the penetration of dust and moisture. It is similar to a blister pack.

Stretch film stretches easily, it will take impressive force to pierce it. At the moment of contact of the layers, they adhere tightly to each other. Finds its application in the wrapping of pallets, preventing them from destruction.

Laminated film is a combined material based on several layers. It has a long shelf life for the packaged product.

The foamed film has a flexible, porous, foamed backing. They are used for packing glass, fragile and breakable products, dishes, electrical engineering and microelectronics. Shockproof, protect from scratches and chips.

Metallized lavsan film has found its application in floor, roof, wall insulation and ventilation equipment. It is based on aluminum and lavsan. The thinner the metal layer of the film, the weaker it repels infrared radiation.

A-PET films are resistant to negative temperatures. They are used for the production of packaging for ice cream, semi-finished products, frozen vegetables.

PET film properties

In general, all types of PET films have the following talents:

• high transparency, gloss;
• excellent rigidity;
• high impact resistance at high and low temperatures (+150 - -75 ° С);
• destruction begins at almost 300 ° C;
• chemical resistance (to the main classes of chemicals);
• low gas and moisture permeability;
• simple painting technology without metallization;
• easily stretches, remaining strong to tear and puncture;
• requires low heat input for molding;
• ease of color printing on its surface;
• the possibility of using different types of processing and recycling.

Operational properties of the product

Basically, the properties of the product are determined by the basic set of qualities of raw materials, but, as already mentioned, in the process of industrial processing, polyethylene terephthalate can be modified. In its pure form, PET film is transparent, amorphous, heat-resistant and environmentally friendly. However, in special versions, the following qualities can be improved:

• Fire resistance - due to the inclusion of flame retardants.
• Mechanical strength - achieved by strengthening the polymer chain, which leads to an increase in the ability to crystallize.
• The increase in melting point and reinforcement within the structure is the effect of adding a phenylene group.
• Anti-adhesion.
• High adhesive capacity.

Applications of PET film

The main purpose of the material is associated with the manufacture of containers for a wide variety of products from small bottles to large equipment. In this capacity, the film is used both in industry and in everyday life. Triplex models are widely used for packaging aseptic and hot products with temperatures up to 100 ° C. In some areas, the practice of using such a film is becoming obsolete.For example, not so long ago, a radio-technical film for cassettes of audio and video recorders was produced from polyethylene terephthalate, but today products with a similar structure are used only as part of film air conditioners. Conversely, there is a great deal of interest in PET film-based composite products in construction. What it is? These are heavy duty thick garbage bags. Construction waste presents a lot of problems during cleaning due to the risks of cuts and punctures in ordinary bags, so reliable and practical PET containers are in great demand.

The use of pet in everyday life

Today, most of the food industry uses PET packaging to package their products. This is beneficial from an economic point of view, because the cost of the material is low. Also, a large percentage of use relates to its intended purpose - electrical insulation. But there are also less popular forms of use. These include PET thermoforming films and PET lamination films.

In itself, thermoforming is the process of obtaining a product of the desired type by heating the plastic. It is most commonly used to create plastic boxes, disposable food boxes and containers. The main types of blisters obtained in this way:

• Bilateral,
• For welding,
• With a folded edge,
• Tuba,
• Mini showcases,
• Molds for individual storage.

In terms of its physical characteristics, the thermoforming type is notable for its greater impermeability to odors and gases, which means that the products will last longer without losing taste or smell. It is convenient for making blisters with elasticity, so there are no white stripes on the fold lines of the packages, as happens with PVC films. Ease of coloring and processing attracts manufacturers with the perspective of the author's design.

The next type is PET film for lamination. Thanks to her, at the moment, an irreplaceable type of sealed packaging has appeared - vacuum. This is the latest technical advancement in food storage. With the help of a vacuum, food can be stored for six months or more. You can also use PET film laminated with polyethylene for printing. In addition to frost resistance, it also has high optical properties.

Storing BOPP films

BOPP film must be stored in a suitable environment. The first requirement is dryness and lack of constant contact with direct sunlight (even those species that are least affected by the sun are negatively affected, especially if the light falls over a long time). The required storage temperature is not more than 30 degrees Celsius (a large one will accelerate the decrease in the level of corona treatment), in addition, it is necessary to maintain a distance of at least 1.5 meters from the heaters. Storage without heating is allowed, but to return to performance, the film must be kept for two days at room temperature. As you can see, even such a successful invention of the chemical industry as BOPP film has many varieties that allow you to achieve the desired characteristics at a minimum price. In addition, the largest manufacturers still recognize this material as promising, so new modifications may appear on the market soon.

Characteristics and properties

Polyethylene terephthalate films are produced in strict accordance with GOST 24234-80.

The main characteristics of mylar films include:

• increased shock resistance at temperatures from -75 to + 150;
• destruction of the material begins when heated from +300 degrees;
• inertness to all major categories of chemicals;
• reduced moisture and gas permeability;
• the possibility of painting without the need for metallization;
• elasticity combined with high tensile strength;
• ease of color printing on the PET surface;
• low heat consumption when forming products;
• the possibility of using different types of recycling and processing.

However, thermal welding of this material presents certain difficulties due to crystallization and shrinkage, which increase the brittleness of the material.

Among the disadvantages of the film, one can distinguish reduced resistance to prolonged action of alkaline solutions, therefore it is rarely used for packaging liquid soap, shampoos and some other types of products containing alkalis.

Applications

The main areas of application of mylar film:

• production of fibers of various types (lavsan and others);
• production of films of various types (laminate, vacuum, shrink, polarizing, printing, stretch, holographic);
• production of packaging both in the structure of multilayer products based on a combination of paper and several layers of plastic, and separately.

A relatively new direction of using lavsan film can be called the auto industry, where it is used to cover elements of compressors, electrical boards, auto body elements, as well as connectors, pumps and other parts.

PET film is used in motors, transformers and other electrical devices to act as heat-resistant insulation in the winding. Such a cable retains its integrity and functionality under the influence of weather conditions, sea water and high soil acidity.

Lavsan film is in demand in the manufacture of containers, artificial fabrics, as well as car tires. Many composite materials used in mechanical engineering are based on PET films.

Lavsan fibers are widely used in various sectors of the foreign and Russian economy. They serve as the basis for the production of polyester materials for a wide variety of purposes: reinforced drive hoses and belts, awning cloths, packing tape, car airbags, floor coverings, gimbal fabrics, as well as geofabric and banner coverings. High quality thermopackaging films are used to pack perfumery and pharmaceutical products. In most cases, packaging for household chemicals is also made of polyester film.

More than 80% of all PET packaging is made from granules.

Varieties of PET films

1. OPET - various types of electrical insulation, polarizing film, etc. are made from it.
2. BOPET is distinguished by its special puncture resistance and thickness up to 4 microns; it is used for various types of flexible packaging (liquid and viscous food products, household chemicals, feed, etc.).
3. PET-G - used in the production of shrink labels.
4. A-PET - due to its thermal and shock resistance and hardness, is used in the production of packaging containers for frozen products.

Due to its plasticity, unsurpassed barrier characteristics, PET film is widely used in the packaging production of blisters and correctors for food products and packaging of technical spare parts and stationery, household appliances and souvenirs.

Varieties of PET blister packaging

Double-sided packaging made of rigid PET film is in two forms, folding into a kind of envelope with grooves for each part or part of the entire product and fastened with locks, which are special protuberances of the groove. Allows you to store and safely transport goods of any shape and size. Due to its relatively high cost, it is used for fragile and small parts.

With a folded edge - ode the form has folded edges, into which a cardboard or plastic base is inserted and fixed with glue or staples. Simple and inexpensive, it allows you to colorfully pack small items.

For welding - similar to the previous version, but it is connected to the base by gluing the flat edge of the form to the cardboard base.Excellent value for money.

Tuba - the original shape, stylishness and practicality of packaging allows it to be used for almost all types of products, from small stationery to gift bottles of wine or toys. Convenience of decoration and transportation, both empty packaging and with goods, make it very popular.

Showcases - lightweight and practical PET showcases are great for mobile decoration of any retail outlet. At the same time, it is almost impossible to use them for third-party goods, since the showcase is made with special shapes for a certain type of product.

Cutting-out is a transparent plastic box for stylized packaging of toys and confectionery products, souvenirs and high-quality textiles, cosmetics and a variety of stationery.

Correxes are a form for single-piece packaging of various goods, most often boxed chocolates. Transparent or metal-like "silver, copper or gold", it increases the transportability of the product and keeps its external characteristics at a high level for a long time.

Multi-layer packaging

Single-layer packaging films are being replaced by multilayer containers (3-7 layers), usually consisting of a protective inner PET film, a cardboard base, a metallized layer, a decorative paper layer and an outer protective PET layer. Often, when producing such a unique material, a combination of several methods is used: coextrusion and lamination, lamination and extrusion, etc.

In this type of packaging, the polymer is an indispensable part, protecting both the product from damage and leakage, and protects the packaging from destruction when the product hits it and exposure to light, moisture and temperature. It is used for packaging juices, milk, baby food, etc.

Species overview

A wide variety of film products are produced on the basis of polyethylene terephthalate, which may differ in their structural structure and, accordingly, in operational characteristics.

Packaging

Packaging represents the core segment in which film coatings were originally introduced. Today, PET film is used for casings for cosmetics, household chemicals, and feed. Depending on the structure of the material, the following types of packaging film are distinguished:

BOPET - is characterized by high puncture resistance, is optimal for creating flexible plastic packaging, therefore it is actively used for packaging viscous and liquid products;

In recent years, a multi-layer packaging container has become widespread, consisting of a three-layer film, a cardboard base, a metallized coating and an outer paper coating.

When producing this packaging material, several technological methods are usually used:

• coextrusion - lamination;
• lamination - extrusion, etc.

In this type of packaging, the polymer becomes an important element, since it is he who protects the product from leakage and deterioration. Lavsan film protects the package from pathogenic microflora getting on the finished product, from the action of ultraviolet radiation, heat and moisture. It is widely used for packaging baby food juices and fermented milk products.

Several types of packaging are created from PET film:

• double-sided - consists of two layers connected with each other with a lock, each part has protrusions and recesses that repeat the shape of the contents of the container;
• blister with folded edges - involves placing a base made of cardboard or plastic;
• tuba - a practical and original container, quite versatile;
• cutting - visually resembles a box, optimal for storing cosmetics, stationery, toys and souvenirs;
• Corrections - used for packing piece products;
• PET showcases are simple and easy-to-use demonstration devices that are optimal for decorating points of sale of goods.

Polygraphic

The material has a rigid structure, therefore it is most often used for outdoor lamination. This category includes PET film in sheets; it is used to cover all kinds of printing products to protect them from adverse mechanical damage.

Insulating

A separate modification of mylar films used to create effective electrical protection for electronic devices and machines without reducing their functional characteristics. Some versions have found application in the creation of cable sheaths.

Metallized

These films are related to the construction field.

The film is often used on metal-plastic windows. In addition, the products are widely used as a heat-saving coating.

Differences in application

Technical film is limited in use, while its cost is significantly lower compared to the cost of the primary one. It is not used, for example, for packaging medicines and food. The rapid destruction of the so-called "secondary" under ultraviolet exposure does not allow its use in greenhouses. The presence of its own odor and less attractive external characteristics should be taken into account when packaging industrial products.

Scope of use

The "secondary housing" found active use as an agricultural film for mulching the soil, for steaming the soil and for arranging feed storage facilities, as well as as a secondary packaging film for doors, windows and other construction mechanisms and components.

Recycled LDPE film is used for finishing construction work, as well as for steam and waterproofing, in addition, it is used for the manufacture of garbage bags. This film is ideal for protecting building materials and equipment from moisture and rain.

In general, construction film can be used everywhere, provided that there is no prolonged exposure to sunlight and the appearance is not important, and also if there are no products, cosmetics or medicines in the place of its application - that is, where it can be dispensed with.

How to choose

Purchase plastic wrap based on net weight (excluding packaging and spool) and film thickness. You can find out the real thickness and price of 1kg of film only by knowing its net weight. Indeed, many film manufacturers significantly underestimate its thickness, taking advantage of the plasticity of the film itself, which cannot be characterized by the same thickness at all points, and the lack of micrometers for buyers.

Weighing the film is the surest way to control film density. That is why specialists in the field of plastic wrap always focus on the price not per running meter, but per kilogram.

If, in the process of choosing a supplier, you went to a site that provides information only about the thickness of the film, but there is not a single word about the weight of the roll, leave from there, despite the attractiveness of its price. The actual thickness will not correspond to the declared one with almost 100% probability. For example, in the markets of the capital, the thickness is usually underestimated by 45-55%.

According to the standards, the final weight of a roll of 1 or 2 grade film with a width of 3 m, a thickness of 100 microns, with a 100-meter winding length should be equal to 27.6 kg. Unfortunately, due to the high cost of this quality film, it sells very poorly. Even in our country, the premium 100 micron film has a real thickness of 90 microns, since it weighs 25 kg. However, with the help of our equipment, a film of 10% thickness difference is produced (i.e., the thickness varies within 81-99 microns), therefore such a film has full compliance with GOST, which determines a thickness deviation of ± 20% (i.e. 80- 120μm) for premium grade.

MegaPlast produces secondary and primary films. Data on the price of the product per kilogram and its net weight can be clarified by calling (495) 970-43-59.