Thermoplastic molding: Applications, Advantages & Disadvantages a

Thermoplastic injection molding process offers a flexible and efficient approach to manufacturing diverse plastic products with minimal cost and lead time. Let's find out with EuroPlas now!

If you are looking for more details, kindly visit SUNUA.

Table of Contents

1. What is thermoplastic molding?
2. Applications of thermoplastic molding
3. The Advantages and Disadvantages of thermoplastic molding
4. Ideal material to use
5. The differences between thermoplastic molding and thermoset molding
6. About European Plastic Company

1. What is thermoplastic molding?

Thermoplastic molding commonly referred to as plastic injection molding, is the method used to manufacture plastic parts and products in massive quantities. The special feature of this technique is its capability to repeatedly melt and solidify thermoplastic materials while retaining their original properties. Consequently, this process typically produces plastic merchandise with high precision, stable physical properties and a smooth glossy exterior.

Typical structure of Thermoplastic Molding Machine

Thermoplastic molding typically commences by melting thermoplastic materials in the form of pellets or granules inside an injection molding machine that operates under elevated temperature and pressure. Subsequently, the molten plastic transforms into a uniform liquid state, ensuring homogeneity of the material.

Once the plastic is in its molten state, it is injected into the mold through the force exerted by the large screw system. The molds utilized for this purpose are typically constructed from steel and meticulously designed to create the desired shape. Once the entire liquid resin has been injected into the mold, it undergoes a cooling process facilitated by a cooling system embedded within the mold, as a result, the plastic solidifies and takes shape.

To obtain the final product, the mold holding the frozen part is opened, allowing for the separation and ejection of the solidified plastic. This marks the conclusion of a multi-step process. A plastic injection molding system generally automates and controls this procedure, which helps ensure gentle and precise impact to avoid any potential damage to the product.

Find out more details about thermoplastic injection molding at Iqsdirectory!

2. Applications of thermoplastic molding

Applications of thermoplastic molding

Thermoplastic molding is extensively applied across multiple industries due to its adaptability and effectiveness. Within the automotive sector, it is utilized for producing both interior and exterior components like dashboards, headlights, and front bumpers. By using this technique, automakers can enhance productivity while delivering durable and visually appealing products to customers.

Thermoplastic molding holds a significant position in the medical industry for its crucial role in producing medical devices of consistent and high quality. Components such as endotracheal tubes, surgical instruments and various medical devices demand an extremely high level of precision. Thermoplastic molding enables the creation of medical products that comply with rigorous safety and effectiveness standards, thereby enhancing the overall quality of patient healthcare.

Thermoplastic molding is a common occurrence in our day-to-day lives, playing a crucial role in the manufacturing of consumer goods like household appliances, equipment, and packaging materials. It also holds significant importance in the electronics industry for producing enclosures, connectors, and components.

Additionally, thermoplastic molding finds applications in aerospace and construction sectors. Its ability to achieve remarkable precision, durability, and cost-effectiveness has made it the preferred choice in numerous industries.

3. The Advantages and Disadvantages of thermoplastic molding

Thermoplastic molding offers numerous benefits that make it a preferred choice across various industries. Firstly, this process offers immense design flexibility, enabling the creation of intricate shapes and sizes.

Secondly, thermoplastic molding is economically viable due to its capacity for mass production, resulting in reduced production costs. Furthermore, Thermoplastic molding ensures high output quality, delivering finished merchandise that meet dimensional and material specifications accurately.

Additionally, this production process is environmentally friendly as it utilizes recyclable materials and minimizes waste generation. In summary, the benefits of thermoplastic molding encompass adaptability, cost-effectiveness, superior product quality, and environmental sustainability.

The benefits of thermoplastic molding

On the other hand, alongside its exceptional advantages, thermoplastic molding also presents certain inherent weaknesses. One of the most significant drawbacks of thermoplastic molding is the relatively high initial investment cost associated with tooling and mold design. This process necessitates a profound level of specialized expertise in order to produce precise molds and tools.

While the eco-friendliness of thermoplastic molding is widely recognized, it is crucial to exercise caution when choosing input materials and avoiding the utilization of detrimental chemicals and additives during production. Additionally, a constraint emerges from the selection of raw materials since thermoplastic molds can only operate optimally with compatible substances.

Moreover, if any unexpected issues arise during the molding process, addressing them can prove to be intricate, requiring a significant investment of time, effort, and financial resources. In general, thermoplastic molding provides abundant benefits to both manufacturers and consumers, nonetheless, it remains crucial to thoroughly evaluate the inherent limitations of this procedure and establish suitable measures to mitigate them.

4. Ideal material to use

What’s ideal material for thermoplastic molding?

Thermoplastic molding is a common manufacturing process that uses various types of plastic materials. Some commonly employed materials for this technique include polyethylene (PE), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC), acrylonitrile butadiene styrene (ABS), and polyethylene terephthalate (PET). These materials possess unique properties that render them suitable for different applications.

PE is renowned for its strength and resistance to chemicals, making it ideal for applications like containers and piping systems. PP exhibits exceptional heat resistance and finds extensive use in packaging, automotive components, and household appliances. PS is available in both rigid and porous forms and is commonly utilized for disposable utensils, packaging materials, and insulation. PVC is well-known for its insulating properties, making it a favorable choice for cables and wiring.

ABS is a robust material known for its ability to withstand impacts, making it well-suited for applications in electronics, auto parts, and toys. Lastly, PET is a transparent and strong material commonly employed for beverage bottles and food containers. In summary, these materials share the common characteristic of being easily melted, shaped, solidified, and transformed into a wide range of products.

5. The differences between thermoplastic molding and thermoset molding

When it comes to injection molding, thermoplastic molding and thermoset molding are the two commonly favored processes. Despite having similar names and some similarities, they possess distinct characteristics and find applications in diverse fields.

Thermoplastic molding Thermoset molding During the manufacturing process, the plastic material is melted and injected into the mold During production, cold material is injected into hot mold Can be remolded and recycled Can’t be remolded or reshaped 100% reversible, as no chemical bonding takes place during the process Forms a permanent chemical bond Thermoplastics result in accurate, flexible, and pleasing surface finishes Comparatively difficult to surface finish Requires high temperature and high pressure Does not requires high temperature and high pressure The production process includes injection molding, extrusion and blow molding The production process includes compression, transfer and casting

Think of the products made from thermoplastic molding like cheese and thermoset molding like a burger patty. Cheese comes in a variety of different shapes but when melted it can take on a new form. Once cooked, a burger patty can’t be melted to take on a new form.

6. About European Plastic Company

6.1 Bioplastic Compound

BiONext is a specific type of bio-engineering plastic produced from biodegradable base plastics and carefully chosen additives to suit the specific needs of end products. It finds extensive use in various industries including but not limited to blowing biofilm, food packaging, agricultural film, injection molding, and extrusion processes for creating items such as spoons, forks, laminations, and plates.

Bioplastic Compound

6.2 Color masterbatch

Color masterbatch is a commonly used technique for coloring plastics, which involves combining a conventional plastic base with pigments and suitable additives in the form of masterbatch granules. EuroPlas provides a diverse selection of premium pigments that deliver precise, steadfast, and durable colors.

Color masterbatch

6.3 Plastic Additives

Plastic is susceptible to the influences of environmental conditions and its own inherent factors throughout processing and use. To enhance production efficiency and product quality, EuroPlas presently offers an array of 11 fundamental additives including anti-UV, anti-aging, flame retardant, anti-static, and more.

Plastic Additives

6.4 Engineering Plastic Compound

Compound engineering plastics find extensive application in various industries that demand a high level of technical expertise. This includes sectors like automotive and motorcycle parts, household electrical appliances, electrical engineering, electronic components, and office equipment. EuroPlas products are designed with exceptional attributes such as chemical resistance, impact resistance, wear resistance, and easy structural adjustment to meet rigorous specifications.

Engineering Plastic Compound

6.5 Filler masterbatch

The filler masterbatch comprises a mixture of conventional plastic materials (PP, PE, HIPS, etc.) combined with CaCO3 stone powder and suitable additives, presented as masterbatch particles. The primary objective of the filler masterbatch is to substitute a portion of the main plastic material, facilitating cost reduction during production and ultimately enhancing the competitiveness of the final products.

Filler masterbatch

6.6 Bio filler

BiOMates is a range of plastic fillers produced using biodegradable base resins and appropriate additives tailored to meet the specific requirements of the end product. These bio fillers possess all the exceptional advantages of filler masterbatch while also being biodegradable within 12 months after use, making them highly environmentally friendly.

Bio filler

A thermoplastic is a class of polymer that can be softened through heating and then processed using methods such as extrusion, injection moulding, thermoforming and blow moulding.

Thermoplastics harden once cooled and do not show any changes in chemical property after being heated and cooled multiple times, making them easily recyclable.

Amorphous and Semi-crystalline Thermoplastics

Thermoplastics are made by joining small molecules, called monomers, together to form long chains using a process called polymerisation. A single polymer chain can be made from many thousands of monomers. The atoms in a polymer chain are joined by strong covalent bonds, whereas the forces between chains are weak.

Depending on the type of monomer, polymer chains may have side branches. If a polymer chain has only a few, short side branches then the chains can form ordered, crystalline regions, called spherulites. However, if the chain has many large side branches, then it is not possible for ordered regions to be formed and the polymer is amorphous. Examples of amorphous polymers are polystyrene (PS), polyvinyl chloride (PVC) and acrylonitrile-butadiene-styrene (ABS). Even for polymers with crystalline regions, there are always some amorphous regions between the crystallites, so these polymers are called semi-crystalline. Examples of semi-crystalline polymers are polyethylene (PE), polyamide (PA) and polypropylene (PP). For semi-crystalline polymers, as the temperature increases, the bonds between the polymer chains weaken to create a pliable solid and then a viscous liquid, which allows the plastic material to be shaped to produce parts.

Amorphous plastics are used for applications where optical clarity is required since light is scattered by crystallites. These amorphous plastics are, however, less resistant to chemical attack and environmental stress cracking due to the lack of crystalline structure.

Before a thermoplastic polymer can be used it is normally mixed with additives, such as stabilisers, plasticisers, lubricants, flame retardants and colourants, to improve the polymer’s functionality, stability or appearance. For example, stabilisers are added to reduce degradation due to sunlight or heat and plasticisers can be added to increase the mobility of amorphous chain segments, lowering the glass transition temperature and decreasing brittleness.  

Advantages

The advantages of thermoplastics include:

• Readily recyclable
• Wide range of mechanical properties
• Light weight compared to metals
• Aesthetically-superior surface finish compared to thermosets
• Good chemical resistance
• Energy efficient processing

Disadvantages / Limitations

Despite the many advantages, there are also some limitations associated with thermoplastics. Due to their low melting point compared to metals, thermoplastics are inappropriate for use on some high temperature applications. In addition, some thermoplastics are susceptible to creep when exposed to long-term stress loads. 

Examples and applications

Thermoplastics come in a range of types with their own unique applications. Examples of thermoplastic polymers include:

The company is the world’s best thermoplastic compounds supplier. We are your one-stop shop for all needs. Our staff are highly-specialized and will help you find the product you need.

1. Polyethylene

Polyethylene is the most commonly used plastic in the world. It is in fact a family of materials that come with a range of densities and molecular structures, each with their own applications. Trade names include Alathon, Borstar, Dowlex, Eltex, Finathene, Hostalen, Lacqtene, Lupolen, Rigidex and Vestolen A. Strong and resistant to most chemicals, ultra high molecular weight polyethylene (UHMWPE) is used to manufacture moving machine parts, bearings, gears, artificial joints and bulletproof vests. High density polyethylene (HDPE) is used to make items such as chemical tanks, gas and water pipes, toys, shampoo bottles and margarine tubs. Medium density polyethylene (MDPE) is used for gas and water pipes, packaging film and pond liners. Linear low density polyethylene (LLDPE) is used for plastic bags, shrink/stretch films and food packaging. Being the softest and most flexible of these materials, low density polyethylene (LDPE) is used for the manufacture of squeeze bottles, sacks and sheets.

2. Polypropylene

Polypropylene is the second most widely used commodity polymer in the world. It is used across a wide range of industries to create items including reusable food containers, sanitary products, heat resistant medical equipment, ropes, carpets, car batteries, cable insulation, storage bins, and even banknotes! Trade names include Adstif, Clyrell, Hifax, Hostalen, Inspire, Isoplen, Moplen, Novolen, and Vestolen.

3. Polyvinyl chloride

Being tough, lightweight, and resistant to acids and bases, polyvinyl chloride (PVC), also known as vinyl, is used by the construction industry for items including water pipes, drainpipes, gutters and roofing sheets. Trade names include Astraglas, Benvic, Vestolit and Vinnolit.

PVC can also be made more flexible with the addition of plasticisers, where it is used for hoses, tubes, electrical insulation, clothing, upholstery and inflatable products such as waterbeds and pool toys. Trade names include, Acvitron and Lifolit.

4. Poly(ethylene terephthalate)

Poly(ethylene terephthalate) (PET) or polyester has a good combination of mechanical and thermal properties, chemical resistance and dimensional stability. It is used for liquid containers, especially carbonated soft drinks, food containers and, in fibre form, for clothing. It is the most recycled polymer worldwide. Trade names include Dacron, Eastapak, Rynite and Terylene.

5. Polyamide

Polyamide (PA) is also known by the trade names Nylon, Akromid, Akulon, Grilamid, Grilon, Rislan and Ultramid. It was originally used as a replacement for silk when making items such as flak vests, parachutes and stockings. Nylon fibres are also used for fabric, carpets, rope and strings for musical instruments. It is also used for machine screws, gear wheels and power tool casings.

6. Polystyrene

Polystyrene (PS), also known by the trade names Styron and Vampstyr, is manufactured in different forms that are suitable for different applications. It is used to make items such as disposable cutlery, cases for CDs and DVDs, and smoke detector housings. Expanded polystyrene (EPS) foam, also called by the trade name Styropor, is used for insulation and packaging materials and extruded polystyrene foam (XPS), also called by the trade name Styrofoam, is used for architectural models and drinking cups. Elsewhere, polystyrene copolymers are used for the manufacture of toys and product casings.

7. Acrylonitrile-butadiene-styrene

ABS, also known by trade names Cycolac and Ensidur, is a lightweight polymer  that shows high impact resistance and mechanical toughness compared to most thermoplastics and is widely used in everyday consumer products like toys and telephones. 

8. Polycarbonate

Polycarbonate (PC) is also known by trade names including arcoPlus, Lexan, Makroclear and Makrolon.  Easy to mould and thermoform, it is used in a range of applications in the medical, construction, electronics, automotive and aerospace industries, including safety glasses, bullet-resistant glass, CDs and DVDs, car headlamp lenses and safety helmets. 

9. Poly(methyl methacrylate)

Poly(methyl methacrylate) (PMMA) or acrylic, is also known by the trade names Acrylite, Altuglas, Lucite, Oroglas, Perspex and Plexiglas. It is widely used as a substitute for glass in aquariums, aircraft windows, motorcycle helmet visors and for the lenses on exterior automobile lights. Acrylic is also used for signage, for eye lenses and in bone cement for medical use, and also in paint, where PMMA particles are suspended in water.

10. Polyoxymethylene

Demonstrating a high stiffness, good dimensional stability and low friction, polyoxymethylene (POM), also known as acetal, polyacetal and polyformaldehyde, is used for parts that require high precision, such as bearings, valve parts, gears and electrical components, and is also known by the trade names Celcon, Delrin, Duracon, Hostaform, Kepital, and Ramtal.

11. Poly(lactic acid)

Derived from renewable resources like sugar beet pulp, corn starch, chips, sugarcane and tapioca roots, poly(lactic acid) (PLA) is a compostable thermoplastic. It is used in tableware, food packaging and additive manufacturing (3D printing). Trade names include Bio-Flex, Fozeas and Ingeo.

12. Poly(phenylene oxide)

Poly(phenylene oxide (PPO) offers a range of attractive properties, including high impact strength, heat distortion, and chemical stability against mineral and organic acids. It also offers low water absorption, but can be difficult to use due to the high processing temperature. Commercial resins, such as Noryl, blend PPO with high impact polystyrene (HIPS) to lower the processing temperature, making it easier to process. Applications include electrical components and washing machine parts. 

13. Polytetrafluoroethylene

Polytetrafluoroethylene (PTFE) belongs to a class of thermoplastics known as fluoropolymers, and is also known by the trade names Teflon, Dyneon, Fluon and Hostaflon. It has one of the lowest friction coefficients of any known solid and is well-known for its use on non-stick cookware. It is also used as a lubricant to reduce frictional wear between sliding parts like gears, bearings and bushings. Because it is chemically inert, it is also used for pipes and containers that come into contact with reactive chemicals.

14. Poly(vinylidene fluoride)

Poly(vinylidene fluoride) (PVDF) is another member of the fluoropolymer family. It is also known by the trade names Kynar, Hylar and Solef, and is known for its chemical inertness and resistance, used for engineering sheets and pipes as well as to make powders and coatings. PVDF is also widely used in the chemical industry for piping to transport aggressive chemicals and high purity liquids.

15. Polyetheretherketone

Polyetheretherketone (PEEK) is a high-performance thermoplastic used for a range of engineering applications, including bearings, pumps, valves and medical implants, due to its good abrasion resistance and low flammability as well as low emission of smoke or toxic gases. Trade names include Victrex and Vestakeep.

16. Poly(phenylene sulphide)

Poly(phenylene sulphide) (PPS) delivers superb chemical resistance, electrical properties, flame retardance, and transparency to microwave radiation as well as a low coefficient of friction. These properties mean that, when injection or compression moulded at temperatures high enough to create crosslinks, PPS can also be used to make cookware, bearings and pump components suitable for corrosive environments. Trade names include Torelina and Ryton.

17. Polyetherimide

With a high heat distortion temperature, modulus and tensile strength, polyetherimide (PEI) is used in high performance electronic and electrical parts, including for the automotive industry, as well as in consumer items like microwave cookware. Trade names include Ultem.

18. Polyethersulfone

Polyethersulfone (PESU, PES)  has high hydrolytic, oxidative, and thermal stability as well as a good resistance to alkalis, salt solutions, acids from aqueous minerals, oils and greases. Application include medical components, gas separation membranes and freezer-to-microwave food containers. Trade names include Ultrason and Veradel.

19. Polybenzimidazole

Polybenzimidazole (PBI), also known by trade names including Celazole and Duratron, has a very high melting point compared with other thermoplastics and shows excellent chemical and thermal stability. PBI’s superb stability, retention, stiffness and toughness at high temperatures has lent it to being used for firefighting clothing, space suits for astronauts, protective gloves, welding apparel, wall fabrics for aircraft and for membranes in fuel cells.

FAQs

Are Thermoplastics Recyclable?

Thermoplastics are easily recyclable as the polymer chain does not degrade when heated. Because the chemical bonds within the chain remain intact while the weaker bonds between polymer chains break down, thermoplastics can be melted and re-used repeatedly.

Are Thermoplastics Safe?

Most types of thermoplastic are safe to use as intended. However, there have been concerns raised over PVC because of the vinyl chloride monomer (VCM) that is used in production. However, modern manufacturing methods mean that the release of VCM is very low while the residual VCM left in the polymer is so low that it can’t be detected.

Are Thermoplastics Biodegradable?

Most thermoplastics are not biodegradable. However, some thermoplastics, such as poly(lactic acid) (PLA), poly (vinyl alcohol) (PVAL, PVOH) and polyhydroxyalkanoates (PHAs) are.

Are Thermoplastics Brittle?

Below their glass transition temperature (Tg), thermoplastics are brittle and deform by elastic deformation. However, when above their Tg, thermoplastics are ductile and deform mainly through plastic deformation. So, in short, thermoplastics go from brittle to ductile as they are heated through their Tg.

Can Thermoplastic be Remoulded?

Thermoplastics can be remoulded repeatedly by heating and then reforming them into new shapes. 

Can Thermoplastic Melt?

Semi-crystalline thermoplastics melt at a particular temperature when their crystalline regions transition to a random arrangement. This melting point is different for different thermoplastics. Amorphous thermoplastics do not have an ordered structure and therefore do not melt; they have a glass transition temperature, below which the material is brittle and, as the temperature increases, the material softens and becomes more rubbery.

Can Thermoplastic be Painted?

Thermoplastics can be painted to provide a different surface finish. However, you will need to use the correct type of paint so that it doesn’t react with any polymer coating and cause discolouration and lowering weather resistance. Acrylic based paints, including spray paints, are a good option for painting thermoplastics.

Can Thermoplastics be Welded?

Thermoplastics can be welded using a variety of different techniques. You can find out more about welding thermoplastics here.

Conclusion

Thermoplastics are polymers that can be softened through heating before being processed and then left to cool and harden. Once cooled, they show no changes in chemical properties, meaning they can be re-melted and re-used several times.

There are many types of thermoplastic, each with their own distinct applications and properties, including being non-stick, tough, flexible, and so forth.

Thermoplastics are synthesised from a range of different materials, including renewable and biodegradable resources such as sugar beet, and have uses in industries including construction, aerospace, automotive, electronics, rail, oil and gas, and power, as well as for a huge range of domestic and consumer products.

TWI

TWI provides our Industrial Members with support in using a wide range materials, including thermoplastics. Our expertise includes testing different plastics and composites as well as materials selection and joining methods for polymeric materials used in different applications.

TWI is an Industrial Membership based organisation. TWI's experts can provide your company with an extension to your own resources. Our experts are dedicated to helping industry improve safety, quality, efficiency and profitability in all aspects of materials joining technology. Industrial Membership of TWI currently extends to over 600 companies worldwide, embracing all industrial sectors.

Contact us today to find out more:

For more information, please visit low smoke zero halogen lszh.