Frontier Recycling Products

Acrylonitrile Butadiene Styrene (ABS)

ABS has a good balance of properties making it one of the most versatile plastics available. Combined with its toughness, strength and temperature resistance coupled with its relative ease in moulding and high quality surface finish makes it excellent when a smart finishes are required.
ABS can be readily modified with additives, reinforced with fibres, blended or alloyed with other polymers so improving its properties and usages. The various special versions available include improved UV stability, high gloss, heat resistance, electroplating, flame retardancy and glass reinforced grades.

Applications:

ABS applications include domestic appliances, automotive, electrical and electronics industries. This covers such products as waste pipes, kitchen gadgets, car trim, and computer cases. Many standard grades have FDA, European and Japanese food accreditations.

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Ethylene Vinyl Acetate (EVA)

The description covers a broad range of grades with vinyl acetate contents between 2 and 50%. Compared with LDPE, they are less crystalline and more polar, ranging from thermoplastic (low vinyl acetate level) to elastomeric (high vinyl acetate level). At levels vinyl acetate levels above 50%, the resins are completely amorphous.

Increasing vinyl acetate content improves the clarity, low temperature flexibility, stress crack resistance, and impact strength. There is also an increase in the "tackiness", in adhesion properties and solubility in common solvents. There is a corresponding decrease in the softening and heat sealing temperature, and barrier properties.

EVA's can be satisfactorily processed by all the normal techniques. As a general guide, resins used for injection moulding have vinyl acetate levels in the 2 to 10% range, extrusion in the range of 5 to 30%, and for blow moulding levels are usually below 5%.

They have limited thermal stability, which necessitates that processing temperatures are maintained below 230(C, above which the acetoxy bonds break to yield acetic acid.

EVA's can be satisfactorily processed by all the normal techniques. As a general guide, resins used for injection moulding have vinyl acetate levels in the 2 to 10% range, extrusion in the range of 5 to 30%, and for blow moulding levels are usually below 5%.

They have limited thermal stability, which necessitates that processing temperatures are maintained below 230(C, above which the acetoxy bonds break to yield acetic acid.

Applications:

EVA packaging film is by far the largest application area, being used for meat and poultry wrap, cereal/carton liners, stretch film, produce bags, bag-in-box, etc. Also included in this area are the extrusion coated polyester, cellophane, and polypropylene films used for cheese wrap, medical film, etc.

The second largest market for EVA is for adhesives, carpet backing and wax based coatings, where grades are sometimes modified with additives.

Usage for wire and cable covering, where the EVA can be more easily cross-linked than the homo-polymers, and for the carrier for some 'universal' masterbatches, is the third most important area of application. Grades are also used for injection moulded of bottle closures, shoes, blow moulded bellows.

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High Density Polyethylene (HDPE)

Polyethylenes are some of the most extensively used polymer type due to their acceptance to be processed and relatively low cost.

The high density range of HDPE (0.941 – 0.965) is due to the more crystalline structure of the polymer when compared to LDPE. It makes HDPE a harder and stronger material especially when compared to the softer LDPE plastics. HDPE takes on a more whitish at best translucent colour in its natural form.

Processing is comparatively easy by film blowing, injection moulding, blow moulding, rotational moulding and extrusion processes.

Further modifications of the plastic can be made by adding various compound and addititves. This can include such compounds as stabilisers, anti-slip, antistatic, flame retardants and antibacterial agents.

Applications examples:

The main usage is film in the forms of stretch, shrink and cling films; Supermarket Carrier bags; Plastic Milk bottles; Used in food packaging where an oxygen or carbon dioxide barrier is not required; Snack food packages; Cereal box liners; Other significant uses are for injection moulded food and dairy product containers; Blow moulded bottles for water and non-carbonated drinks; Due to its stable chemical resistance it is used for blow moulded household detergents and bleach bottles as well as other industrial containers for chemicals and acids; Injection moulded housewares and wheelie bins; Rotationally moulded industrial and agricultural storage containers.

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Low Density Polyethylene (LDPE)

Polyethylenes are some of the most extensively used polymer type due to their acceptance to be processed and relatively low cost.

The low density range of LDPE (0.910 - 0.930) is due to the crystallinity of the polymer. It makes LDPE a soft and flexible material especially when compared to the tougher HDPE plastics.

Processing is comparatively easy by film blowing, injection moulding, blow moulding, rotational moulding and extrusion processes.

Further modifications of the plastic can be made by adding various compound and addititves. This can include such compounds as stabilisers, anti-slip, antistatic, flame retardants and antibacterial agents.

LDPE is generally used in film application (sandwich bags and bread bags) due to its robustness, flexibility and transparency. It is popularly used in processes where heat sealing is necessary due to its low melting point.

Other examples of LDPE applications include:

Shrink wrap and cling films; Covering of dry cleaning garments; Rubbish bags; Flexible storage packaging for use in fridges and freezers; Injection moulded food product containers; Blow moulded bottles for water, detergents, bleach, chemicals; Blow moulded car petrol tanks; Extrusion process produces pipe (sewage, water etc); and is also widely used in wire and cable applications due to its stable electrical properties.

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Polyethylene Terephthalate (PET)

Polyethylene terephthalate is a ubiquitous plastic and its major use is in the producing of transparent containers, often for bottles which hold pressurized and soft drinks. This is due to it having excellent barrier properties to water vapour, oxygen and carbon dioxide. It is a heat resistant polymer, with very good toughness, clarity and gloss, and good electrical properties. In homopolymer form, its crystallinity is difficult to control, but copolymers are more easily processed.

Grades can be processed by all the conventional thermoplastic processes, including fibre production and stretch blow moulding.

Applications:

There are various variants of PET available including:

Oriented PET (OPET), or stretch blown PET often used for drinks containers as well as containers for oils, pharmaceuticals and household products.

Amorphous PET (APET): This is often produced as sheets and used in thermoforming packaging due to its excellent clarity, gloss and grease resistance.

Crystalline PET (CPET), opaque as its natural colour with a wide temperature tolerance, is the version used for food packs intended to be transferred directly from the freezer (-40 C) to the oven ( 200 C). It is opaque as natural colour.

PETG: The glycol modified PET is amorphous and retains clarity in thick sections. It is used for medical and pharmaceutical applications, as well as food and personal care packaging, and blister packs.

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Polypropylene (PP)

Polypropylene is the second most used plastic in Western Europe after polyethylene. This is due to its semi-rigid, translucent properties as well as having good chemical and heat resistance and tough, fatigue resistant nature.

It is a versatile plastic due to its high degree of crystallinity and heat resistance, its density lies between that of LDPE and HDPE, so meaning it is less tough that LDPE and much less brittle than HDPE. Its high reistance to fatigue means it makes good living hinges eg lids of Tic Tac boxes.

It is available in two types, homo-polymer and co-polymer grades.
The homo-polymer grades can be used unfilled or compounded with a wide range of reinforcing fillers to improve heat resistance, rigidity and creep properties. Filler loadings can be as high as 50% or more.

Copolymers, using relatively small amounts of co-monomers, have improved low temperature toughness, optical properties and processability, but with corresponding reductions in rigidity and heat resistance. Mould shrinkage for both types is high compared to other common polymers.

Applications:

It is widely used to produce fibre and monofilament for cordage, rope, carpet backing and facing yarns, upholstery and automotive fabrics, medical fabrics and filters, woven bags and strapping tapes.

Many toys, appliance and automotive components e.g. bumpers are injection moulded using PP.

Extruded sheet is used for chemical plant linings and thinner sheet is used for packaging.

Blow moulded copolymer containers for example food or medical packaging are produced due to the transparency and high melting point (160 degrees Celcius) as then they will not melt in dish washers or hot filling industrial processed. Polypropylene is often the main component in co-extruded multi layer barrier structures for many food packaging applications.

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Polyvinyl Chloride (PVC)

Polyvinyl Chloride has two main forms rigid or PVCu, and plasticised or flexible PVC.

It has excellent transparency, a good chemical resistance; long term is very stable; has good weatherablity; and has stable electrical properties.
It is the third most widely used plastic material after polyethylene and polypropylene.

However due to its rigid polymer structure it makes PVC difficult to process for most applications. Its rigid form needs heat stabilizing, processing aids, and often impact modifying and light stabilizing with process temperatures not to exceeding 200 C.

Its usage can be thin films though to rigid pipe and complex moulded applications.

Other Applications:

Rigid PVC main use is in extruded pipe and extruded window frames, electric trunking, siding and outdoor construction products. It is injection moulded into computer housings, electrical fittings. It can be blow moulded into bottles for water and beverages.

In the plasticised form, when additives may constitute 40% to 60% of the (mainly plasticiser) compounded mix, it is used extensively for extruded wire and cable insulations for use in buildings, automotive, electrical and electronic appliances. It is also used for automotive exterior trims and mouldings. In the medical field it is commonly used for tubing applications. It can be calendared into flooring and floor tiles, and is used in horticulture, footwear, and industrial tubing. In dispersion form, it is used in fabric coating to produce, for instance, 'leather cloth' and wall coverings.

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