Bonding And Gluing Plastic: Find The Right Solution For Your Challenge

PE (polyethylene) is the most widely used thermoplastic in the world. PE is used to make plastic bags, beer crates, tubes, buckets, bottles, cling film and seals. PE is tasteless, odourless and physiologically harmless as well as resistant to acids, alkalis, salt solutions, fats and oils. Foils are usually made of the softer high-pressure polyethylene, whereas tableware is made of the harder low-pressure polyethylene with a melting range of 125 to 130 °C.

Trade names: Hostalen, Dyneema, Spectra, etc.

PP (polypropylene) is the second most commonly used thermoplastic material, which is used e.g. for food packaging, home textiles, fittings and piping, technical housings, helmets and medical products. More than one third of synthetic fibres are made of PP. Polypropylene has more favourable properties than polyethylene, it is stiffer and has a higher melting range of about 165 °C. This gives it a wider range of applications.

PVC (polyvinyl chloride) is a plastic containing halogen, which is used for drainage pipes, cable sheathing, hoses, floor coverings, window profiles, etc. A distinction is made between hard and soft PVC. In order to achieve favourable usage properties, PVC, unlike other polymers, requires the addition of many additives such as stabilisers, lubricants, plasticisers and others.

Trade names: Hostalit, Vinnol, colloquial: e.g. artificial leather

PA (polyamides) are high-strength and impact resistant. They have a high abrasion and wear resistance. Excellent sliding properties make them a preferred construction material in mechanical engineering or vehicle construction for slide bearings, gear wheels, dowels, screws and nuts or housings. Polyamides are insensitive to fuels and lubricants at temperatures up to 150 °C. A large proportion of polyamides are spun as synthetic fibres. The fibres have a high tensile strength and are used for textiles, climbing ropes, parachutes and hawsers, among other things.

Trade names: Perlon, Nylon, Dralon, etc.

PS (polystyrene) is mainly produced as amorphous thermoplastic. It has low moisture absorption, very good electrical properties and can be processed well. Disadvantages are its tendency to stress cracking, low heat resistance, flammability and its sensitivity to organic solvents. If polystyrene is foamed with carbon dioxide during polymerisation, polystyrene is formed. Areas of application are thermal and perimeter insulation materials, sound insulation, packaging, insulation cases, CD covers, insulation of electrical cables and material for switches.

Trade names: Styropor, Styroform and others

PET (polyethylene terephthalate) is known as a glass substitute in beverage bottles, in filling fibres and as fibres for clothing. In electrical engineering, PET films are used as carrier material for magnetic tapes. PET has high stiffness, hardness, abrasion resistance and is resistant to diluted acids, oils, fats and alcohols. However, it is sensitive to hot steam.

PMMA (polymethyl methacrylate) has intertwined polymer chains. It's very weather-resistant and can be used as a substitute for glass. Optical lenses and spectacle lenses, glazing, lamps and sanitary parts are made from PMMA. It's indispensable in dentistry, where it's used for dentures. For this purpose, the plastic is dyed with metal salts to create the typical pink colour. The applications are manifold. For example, PMMA can be used for polymer concrete, glazing, lenses, optical fibres, bathtubs, light covers and adhesives.

Trade names: acrylic glass, plexiglass

ABS (acrylonitrile-butadiene-styrene copolymer) is today an everyday plastic which is widely used because of its surface hardness, high impact resistance and good resistance to weathering, ageing and chemicals: For example, for sanitary pipes or housings of household and electrical appliances as well as for toys, plates and foils.

Trade names: Cycolac, Novodur, etc., colloquially e.g. styrenics

SAN (styrene-acrylonitrile copolymer) is a transparent copolymer of two transparent plastics: Formed by the copolymerisation of styrene (about 70%) and SAN acrylonitrile monomers (about 30%). This high-performance thermoplastic polymer is often used as a material for greenhouse or industrial glazing and shower cabins due to its weather resistance, rigidity, toughness and scratch resistance.

PTFE (polytetrafluoroethylene) has high chemical inertia, a high dielectric constant, a flame-retardant effect, thermal resistance up to 260 °C, extremely low friction, non-stick properties and high weather resistance. Technically, PTFE is used for bearings and seals in aerospace and mechanical engineering, cable coatings in telecommunications, as a fire protection agent in vehicles and buildings and for coating cookware.

Trade names: Gore-Tex, Dyneon

POM (polyoxymethylene) is one of the most commonly used thermoplastics worldwide. It's valued for its high impact resistance, strength, hardness and rigidity. Due to its low coefficient of friction, high heat deformation resistance, excellent sliding and abrasion behaviour in combination with low coefficients of friction, the material is often used as an engineering plastic - primarily for precision parts such as gears, shafts, switch gears, etc. The high recovery elasticity of polyoxymethylene makes the plastic useful for applications in the field of snap-fit connections.

POM thermoplastics are resistant to diluted alkalis or acids (pH > 4) as well as halogenated, aromatic and aliphatic hydrocarbons, oils and alcohols.

PC (polycarbonate) is a polyester of carbonic acid. This water-clear, thermoplastic material is characterised above all by its glass-like optical properties, but weighs less than glass. The material is therefore often used for lightweight construction purposes, such as panorama roofs or transparent covers for buildings.

UF (Aminoplasts) are thermosets. They are hard and brittle and decompose when heated. Melamine resins, melamine-phenol resins and urea resins are thermosetting, spatially closely cross-linked moulding materials. The cross-linking points are chemical bonds, therefore thermosets have, in contrast to thermoplastics, higher strength, higher elasticity, higher hardness and higher thermal stability. By mixing different resins, multi-component materials are created which are used in furniture construction and for the production of sockets, household appliances and break-proof tableware.

PF (phenoplastics) are thermosetting, spatially closely cross-linked moulding materials. Phenoplastics are polycondensates of phenols (partly also cresols) and formaldehyde, they're inexpensive and used mainly for technical mouldings despite their dark inherent colour and darkening.

NR (natural rubber) consists of latex, the latex of the rubber tree.

NBR (acrylonitrile-butadiene rubber) has a high resistance to oils, fats and hydrocarbons as well as a high abrasion, tensile and tear resistance. NBR hardly charges itself electrostatically and therefore no sparking is to be feared, which is why the material is often used for tank and petrol hoses. NBR is classified as physiologically harmless and is therefore also used in drinking water and beverage production.

SBR (styrene-butadiene rubber) is the most widely used synthetic rubber today and is used in the production of tyres, seals and conveyor belts.

BR (butadiene rubber) is the second most important synthetic rubber. It improves the properties of natural rubber.

CR (chloroprene rubber) is a synthetic rubber which is used, among other things, in vehicle construction and for heat-insulating sportswear. Hoses, cable sheathings, seals and drive belts based on chloroprene rubber are often used in the automotive industry due to their favourable combinations of properties. Dissolved in organic solvents, polychloroprene, like the polymer dispersion itself, is also suitable for various adhesives due to its good resistance. The worldwide consumption of chloroprene rubber including adhesives is estimated at over 300,000 tonnes per year.

Trade name: Neoprene

EPDM (ethylene propylene diene rubber) is used for sealing profiles. In contrast to NBR, EPDM has very good electrical insulation properties, excellent resistance to ozone and sunlight, and outstanding resistance to ageing.

Silicones - chemically more precisely known as poly(organo)siloxanes or siloxane - are synthetic polymers whose silicon atoms are connected via oxygen atoms (Si-O-Si). They occupy an intermediate position between organic and inorganic compounds. At present well over 10,000 different types of silicone are known. Silicone rubbers are differentiated according to the temperature required for cross-linking.

The cold-crosslinking HTV silicone rubbers are plastically deformable materials which are used, for example, as cable sheathing, for electrical insulation or for sealing and damping purposes.

The flowable, red silicone rubber (RTB/HB) has a high heat resistance and low elasticity. They are used as mould construction material for casting moulds for low-melting metals where high hardness is required.

In contrast, the low-viscosity, hot-crosslinked silicone rubber (RTV/NV) is medium-elastic, has good flowability and low viscosity. It is therefore particularly suitable for the manufacture of elastic wax or relief casting moulds, casting moulds for figures or decorative panels, moulds for casting with epoxy / casting resin, cement, plaster or other flowable materials.

The highly elastic silicone rubber (RTV/HE) is a quite flowable silicone rubber with very high elasticity and at the same time low viscosity. It is particularly suitable for the production of filigree elastic forms with pronounced undercuts. Fields of application are relief casting moulds or moulds for strongly structured decorative panels or wall elements.

Basically almost all plastics are suitable for foaming, e.g. polyurethane (PUR hard/soft foam), polypropylene, expanded polyurethane (EPP), expanded polystyrene (EPS), expanded polypropylene (EPE). The properties can be determined by the selection of the raw materials. For example, strongly cross-linked rigid foams are produced when short-chain polyols are used, whereas soft to elastic foams are produced with long-chain polyols.

Most foams are produced by means of foam extrusion: the heated plastic expands to 20 to 50 times its volume as it flows out of a perforated nozzle. Rotating knives then cut the resulting foam strands into closed-cell foam particles of a few millimetres in size, from which various products are formed.

Fibre-reinforced composites are mixed or multi-phase materials consisting mainly of reinforcing fibres (e.g. glass, carbon, polymers or ceramics) and a matrix (plastic, synthetic resins) surrounding them. Depending on the area of application, different additives and fillers are added. This makes components made of composite materials more stable and resilient than those made of monocomponent materials, while maintaining the same weight.

This is why composites are often used for lightweight construction applications. The aircraft and vehicle industry, wind power plants and chemical tanks are the main areas of application for fibre-reinforced plastics.

GRP glass fibres are also the most widely used fibre types due to their relatively low price, with a share of over 90%. Depending on the application, the length of typical reinforcement glass fibres is between 10 and 300 µm. Fibres over 1 mm long are already considered long in the field of plastics processing.