Plastic materials

REVOLUPLAST expertise in thermoplastics processing

At REVOLUPLAST, we mainly work with thermoplastic sheets, which we transform using our digitally controlled 3-axis machining centres. This process enables the precise cutting and machining of sub-assemblies, which we then shape and assemble to produce customised projects, without needing a mould.

What is a thermoplastic?

Thermoplastic is a type of polymer that is highly adaptable: it softens when heated and hardens when cooled, a reversible process that can be repeated without altering the material. These properties make thermoplastics extremely versatile, and they are therefore widely used in a diverse range of industries.

Types of thermoplastics used by REVOLUPLAST

We transform a wide variety of thermoplastics, each with its own specific properties and applications:

• HIPS (Polystyrene): Grained appearance on one side, ideal for interior use.
• High Impact ABS (Acrylonitrile butadiene styrene): Grained appearance, more resistant to rubbing and micro-scratches, perfect for industrial and electronic applications, particularly outdoors, with additional UV protection if required.
• PVC (Polyvinyl chloride): Smooth surface, popular in the building industry for its resistance to fire and chemicals.
• PC (Polycarbonate): Available in opaque black or transparent, impact and UV resistant, suitable for applications requiring increased robustness.
• PMMA (Acrylic, ‘Plexi’): Transparent or coloured, with an extruded or cast finishing, often used for design elements.

Some of these thermoplastics offer enhanced fire resistance, meeting safety standards such as M1 or UL94V0
Two main types of test: UL 94 flammability test and glow-wire test.

Properties and Benefits of Thermoplastics

Thermoplastics offer a wide range of technical advantages:

1. Thermoforming et Recycling: Their ability to soften under heat and harden on cooling allows easy thermoforming, with high recyclability, reducing industrial waste and encouraging sustainable practices.
2. Lightweight and strong: These materials are lightweight but robust, an advantage in the transport and mobility sectors, where their use can reduce the weight of components and improve energy efficiency.
3. Resistance to corrosion and chemicals: Some thermoplastics (PVC-PP-PET-PETG) are resistant to chemical agents, but for applications in harsh environments, it's a good idea to test their abilities before selecting them.
4. Insulation properties: Excellent thermal and electrical insulators, thermoplastics are ideal for cables and electrical appliances, helping to minimise heat loss.
5. Properties for radio transmission: Unlike fine sheet metal solutions, plastics are ideal for radio devices or equipment or connected objects (IoT), enabling good Wifi, RFID (Tag, reader...) and microwave communication.
6. Multiple applications: Thanks to their specific qualities, thermoplastics are suitable for a wide range of industries: electronics (housings, covers, terminals), screen protection, transport, healthcare, laboratory equipment, electrical instrumentation, security and public or commercial facilities.

Summary table of the different properties of extruded thermoplastic sheets

Values and properties may vary slightly depending on specific extruder formulations and conditions of use.

Remarks :

• VICAT softening point in C°: Temperature at which the material begins to soften under load.
• UL94 treatment: Flammability classification standard for plastic materials. HB ‘Horizontal Burn’ (the lowest), V-0 ‘Vertical Burn’ (the most fireproof test).
• Impact resistance: Ability of the material to withstand impact(s) without breaking.
• Chemical resistance: Assesses the material's ability to resist various chemicals.
• UV resistance: Capacity of the material to withstand exposure to ultraviolet rays.
• Marking grip: easy and durable marking or printing of the material

A number of polymers are used and can be classified into 3 main categories:

Plastics transform under heat and pressure. They can be moulded and shaped into many different forms.

1. Thermoplastics

Plastic materials most often used. Generally used in the form of granules, powders or sheets that soften under the effect of heat, allowing them to be moulded into the desired shape. After cooling, the plastic hardens and retains its shape.

This operation can be repeated, making thermoplastics recyclable.

This category includes :

• Polyethylene (PE),
• Polyvinyl chloride (PVC),
• Polypropylene (PP),
• Acrylonitrile butadiene styrene (ABS)
• Polystyrene (PS),
• Polycarbonate (PC)
• Polyester and polyethylene terephthalate (PET).

2. Thermosets

These are plastic materials that take on their final shape after polymerisation.

Polymerisation is a chemical reaction that irreversibly solidifies the resin or matrix.

This characteristic means that thermosets cannot be recycled. Thermosets are solid, highly resistant materials.

It includes:

• Polyurethanes (PUR),
• Unsaturated polyesters,
• Phenoplasts (PF)
• Aminoplasts (MF).

3. Elastomers

These are polymers with elastic properties that allow them to stretch and deform. This allows them to withstand large deformations before breaking.

There are 3 categories:

• Rubbers,
• Special elastomers,
• Very special elastomers.

The plastics industry covers a range of processes for manufacturing and processing plastics.

Here is a summary of the main processes used:

1. 1. Injection

This involves melting plastic granules and then injecting them under high pressure into a mould, where they take on the desired shape as they cool.

This technique is used to produce parts in large series with a high degree of precision.

2. 2. Extrusion

This is a continuous manufacturing process in which plastic in granular or powder form is placed in a hopper, lowered into a furnace where it is heated and kneaded until a homogenous, mouldable texture is obtained. The melted plastic is then forced through a die by an endless screw to create long, hollow, flat and uniform shapes (e.g. tubes, drums, sheets, packaging or film).

There are several types of process:

2. 2. • Extrusion of profiles: the material coming out of the extrusion head is cooled in a moulder to match its shape, then passed through a cooling tank and a drawing bench to cut the product to the required length or rolled up. Enables profiles of various shapes or tubes to be produced
      • Blown film extrusion: the material, which has been transformed into a tube with very thin walls, is inflated with air and then stretched to form a cylindrical bubble. It is then cooled and wound into a reel (‘sheath’).

This process is used to make products such as pipes, profiles and packaging.

3. 3. Thermoforming

Involves heating a sheet of plastic to make it malleable. It is then shaped on a mould using vacuum, pressure or a combination of the two. This process is often used to make packaging, trays, bonnets and bodywork parts.

1. 1. Compression moulding

This process is used for thermosetting plastic or composite materials. It involves placing a piece of plastic material in a hot mould, then applying pressure to the material to allow it to conform to the shape of the mould. The heat and pressure allow the material to harden.

These methods can be used to meet a wide range of industrial needs and specific applications, from packaging and automotive components to electronic devices and everyday consumer products.

5. 5. Rotomoulding

Or rotational moulding involves introducing a precise quantity of plastic powder into a hollow mould. The mould is then heated and rotated around two perpendicular axes. The heat causes the plastic to melt and spread evenly over the walls of the mould.

After cooling, hollow parts such as tanks and toys are produced.

6. 6. Blow moulding

Used to make hollow objects. It consists of two main techniques:

6. 6. • Extrusion blow moulding: consists of hot extruding a polymer tube (parison) which is placed in a mould. Air is blown into the parison, forcing it to take on the shape of the mould.
      • Injection blow moulding: a preform is injected, then heated and blown into a mould to produce the final shape.

7. 7. Calendering

The molten plastic is passed between rollers to obtain the required thickness. It is then cooled and cut to size.

This technique is used to produce films, sheets or plates.

8. 8. Pultrusion

Is a continuous process similar to extrusion, mainly used for fibre-reinforced composites. These are impregnated with plastic resin, then drawn through a heated die to form solid profiles.

9. 9. 3D printing

Or additive manufacturing makes it possible to print complex-shaped parts by depositing successive layers of plastic material.

The most commonly used technologies for making models, first series or small series. The impact of the finishing touches also needs to be taken into account.

Different types :

9. • Fused Filament Fabrication (FFF, FDM)
   • Stereolithography (SLA),
   • Sintering
   • Selective Laser Sintering (SLS)
   • Material spraying.

Thermoplastics are essential for applications that require durability, lightness and adaptability. At REVOLUPLAST, we carefully select each material on the basis of its properties to meet the specific needs of our customers. Thanks to our expertise in thermoplastics processing, we can offer tailor-made solutions to meet the most varied requirements.
Do you have a project in mind? Contact us for a quote.