Advantages and disadvantages of thermoforming solutions

Thermoforming solutions offer numerous capabilities for various plastic manufacturing requirements. Discover the advantages and disadvantages to decide whether it’s right for your project.

Thermoforming is a popular solution deployed by many manufacturing businesses. In fact, the value of the thermoforming plastic market is set to rise from $34.8bn to 45.9bn by 2024, with a projected CAGR of 5.7%, taking it to 45.9 billion in 2024.

The rise of thermoforming goes down to the growing demand for plastic packaging across various industries. However, it might not be the right solution for everyone. Read on to discover the advantages and disadvantages of thermoforming solutions.

What is thermoforming?

Thermoforming is the process of heating a thermoplastic material before shaping it into a specific mould. Typically found in manufacturing, thermoforming involves applying a pliable forming temperature to a plastic sheet or film and stretching it onto the pre-designed mould. The process is completed with any final cuts and trims to produce a usable product.

Essentially, the thermoforming process transforms a plastic sheet into a 3-dimensional shape through pliable temperatures, creating a vacuum through pressure. Also known as “vacuum forming”, the thermoforming process is used for packaging across multiple industries, including:

• Food and agriculture
• Healthcare and pharmaceuticals
• Retail
• Business machines and equipment
• Automotive
• Aerospace and aviation
• Building construction
• Mass transit
• Medical equipment
• Recreational equipment and machinery
• Dunnage and containers

With such a dynamic range of capabilities suiting so many industry specifications, thermoforming represents multiple options for manufacturing purposes. Here are some of the methods involved with thermoforming:

Thermoforming methods

Vacuum forming
Vacuum forming is cost-effective and fast, making it ideal for producing a high volume of products. The process involves heating the plastic sheet on a frame before a vacuum is used to suck the air out, forcing the sheet into the mould.

Pressure forming
Pressure forming is a similar process to vacuum which applies an additional measure for improved accuracy and uniform thickness.

Drape forming
Drape forming ‘drapes’ the plastic sheet over the form for a lower-cost thermoforming solution at the price of less accuracy.

Billow Forming
Also known as “free forming”, billow forming uses no mould and applies air jets instead to blast the heated plastic into a bubble for making dome shapes.

Matched mould forming
Matched mould forming offers a highly detailed and accurate finishing using two moulds to make a specific shape.

Twin sheet forming
Two layers are heated simultaneously to form one finished piece, ideal for hollow products.

The advantages of thermoforming

Thermoforming provides multiple advantages to manufacturers and consumers. Here is a list of thermoforming benefits:

1. Cost-effective – Low tooling costs alongside materials make it a cheap plastic moulding solution.

2. Versatile – Thermoforming has the potential to create multiple finished parts from the same material while using numerous types of plastic.

3. Efficient – It can produce high-quality products quickly, suitable for short-deadline product strategies.

4. Larger design scope – Thermoforming can work for large plastic projects, unlike other plastic moulding processes.

5. Simple – Thermoforming offers a simple form of plastic manufacturing technology, requiring less skilled labour.

The disadvantages of thermoforming

Despite having multiple advantages, arguably, there are some disadvantages to be aware of:

1. Design limitations – Thermoforming products are restricted to thin-walled designs and plastic sheets/films.

2. Weak spots – Sometimes thickness can be uneven, causing weak spots. However, choosing the right supplier can mitigate this issue.

3. Excess plastic – Thermoforming can require more plastic than other plastic moulding processes.

What are the main properties of thermoforming polymers?

Thermoplastics are made from polymer resins that become homogenised after heating. The process of homogenisation can involve a variety of thermoforming materials, each with specific applications and functions:

Acrylonitrile Butadiene Styrene (ABS): With a high density and impact strength, ABS is common thermoforming material available in any colour and comes with several textures.

Acrylic (Polymethyl Methacrylate, Plexiglass or PMMA): Acrylic is a clear and abrasion-resistant material, easily formed with various colours available.

High-Density Polystyrene (HDPE): Impact and chemical resistant, HDPE also has excellent cold temperature properties.

High-Impact Polystyrene (HIPS): Easily formed and available in various colours, HIPS is a low-cost option for thermoforming.

High Molecular Weight Polyethylene (HMPWE): Chemical resistant with high impact strength, HMPWE has excellent capabilities for the food and medical industries.

KYDEX (PMMA/PVC): A general all-purpose thermoforming solution, providing chemical and impact resistance, with multiple colours and textures available.

LEXAN: Moisture, flame, and scratch resistant, LEXAN is an excellent thermoforming solution for versatility.

Polycarbonate (PC): PC has a remarkable impact strength with high-temperature resistance, ideal for the automotive industry.

Pennite (glass-filled nylon): Cost-effective, strong, and dense, Pennite is the ideal thermoforming solution metal replacement.

Polyetherimide Ultem (PEI): PEI comes with a natural amber colour, is autoclavable and provides a high-temperature grade material.

Polyethylene Terephthalate (PET): With a clear finish and cost-effectiveness during high-volume manufacturing, PET provides the ideal packaging solution.

Polyethylene Terephthalate Glycol (PETG): PETG has high impact strength and forms well as a clear material. It is ideal for medical-grade products.

Polypropylene (PP): With high chemical resistance and excellent rigidity impact strength, PP performs well at higher temperatures.

Polyvinyl Chloride (PVC): PVC is another rigid thermoforming material with high impact strength and flame resistance.

Royalite: Royalite is a durable material with high tensile and impact strength while working well at high and low temperatures.

Reprocessed Polyethylene Terephthalate (RPET): Another high-performing material used for food packaging, RPET is a clear and low costing thermoforming product.

Thermoplastic Polyolefin (TPO): Available in a high-gloss finish, TPO is ideal for outdoor applications but is challenging to form.

Vinyl: Vinyl conducts electricity while remaining durable and flame resistant.

What is the difference between thermoforming and thermosetting polymers?

Thermoplastics and thermosetting are both polymers but behave differently when heated. Thermoplastics melt under heat while thermosetting polymers retain their form and stay solid. This contrast is down to thermoforming plastics having long chains of loose molecules with no fixed structure or pattern. On the other hand, Thermoplastics contain monomers that join to form larger polymers.

So, once moulded, thermosetting plastics cannot be deformed or reapplied, while thermoplastics can. Thermosetting plastics have dimensional stability and work to tighter measures with superior density.

Contact a specialist thermosetting manufacturer

As cellular solutions specialists, we provide thermosetting materials and services to suit numerous purposes and requirements. With over 50 years of experience and global recognition, we’ve helped manufacture over 60,000,000 products in 27 countries. So, if you’re looking for thermoforming solutions, get in touch today.

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