Thermoplastics are plastic materials that melt under the application of heat. They are formed by the polymerization of monomer units of hydrocarbons and widely coveted for their reliability and diversity. Most plastic manufacturing processes today are possible because of the melting properties of thermoplastics. Thermoplastic materials may be strong, flexible, shrink-resistant, flame-retardant, highly elastic, rigid, opaque, clear or sturdy.
Thermoplastic materials are very recyclable; this means they can be used and re-used by administering heat and re-molding them into the desired shape. This process of re-using thermoplastics will not negatively impact the properties of the material, with the new product performing exactly as intended.
Types of Thermoplastic Materials
There are a number of thermoplastic materials depending on the nature and properties of the plastic. In manufacturing, thermoplastics like polyvinylchloride (PVC), polystyrene (PS) and polyethylene (PE) are the most widely used. This is because of their suitability for packaging, cost and applicability. Other thermoplastic materials include nylon, Teflon, polypropylene, acrylic and polycarbonate.
Thermoplastics are likewise suitable for piping and plumbing systems as alternatives to steel pipes. Because they do not rust and withstand corrosion, thermoplastics are used for both cold and hot materials. Thermoplastic materials may be used in producing bottles, grocery bags, food containers, toys, sport gadgets and even bullet-proof vests.
Thermoplastics for Injection Moulding
Thermoplastic materials represent a large class of injection molding materials, however, there are other plastic types used in injection molding. Generally, plastic may be grouped under two broad categories – semi-crystalline or amorphous plastics.
Amorphous plastics are formless. They may expand or shrink gradually based on the temperature applied to the material. Semi-crystalline plastic on the other hand, have a sharp melting point and are more reactive to changes in temperature. When selecting what type of material to work with, factors such as the application, physical and chemical properties must all be considered to ensure that you work with the best possible material for your part. For instance, you may have to consider if your plastic part needs to be heat-tolerant, food-safe or UV-resistant.
Advantages of using Thermoplastics in Injection Moulding
From recyclability to yield, the following are the reasons why thermoplastic materials are best used in injection molding:
• Ease of prototyping and production
Thermoplastics are very suitable for molding and re-molding operations when using injection molding to prototype. These materials avails testing at relatively lower cost without the need to discard failed prototypes as they can simply be re-melted and re-used.
Thermoplastics are highly recyclable plastic materials that can be used and re-used. By simply applying the right amount of heat, thermoplastic wastes can be re-melted and re-used to make a totally different end part in the injection molding process.
There is a higher overall yield from thermoplastic materials than most other plastic materials. This is due majorly due to the ease of melting and manufacturability in the injection molding process.
• Finishing options
Thermoplastic parts can be subjected to a wide array of finishes depending on the desired output. They are very suitable to numerous post-production processes, allowing for decorations, logo, engraving and painting on your end part.
• High stress and Thin-wall applications
Thermoplastic materials may be elastic and stress-tolerant. They are less likely to deform when milling thin-walled parts. Their flexibility and strength makes them suitable for high-strain applications, meaning they are very suitable for purposes that require day to day uses, high-stress and fatigue.
• Rust and corrosion-resistant
Thermoplastics are chemical retardant and corrosion resistant. These properties make them highly suitable in place of steel, they are also very well suited for medical usage where they can withstand chemical exposure without peeing or contaminating the compounds contained in them.
• High strength-weight ratio
Some thermoplastic materials boast of high strength-to-weight ratio, positioning them as the ideal material when looking for alternatives to metal materials. Thermoplastics are also the only group of plastic that can be welded. They are therefore highly functional, delivering the same strength at lower weight.
Although there are many properties of thermoplastics that make them highly suitable for plastic injection molding, some thermoplastics may experience creep and fracture under long-term stress. In addition, not all thermoplastic materials are chemical-resistant and may degrade faster under UV rays or exposure to sunlight.
First Part Injection Molding Services in China
First Part offers high quality, thermoplastic injection moulding service for all your plastic part projects in China. We also offer low-volume manufacturing that serve small quantities from 50 to 10000 parts and produce for mass production. Our engineers are always available to advice on the best processes, materials and design optimization to ensure cost-savings, quick turnaround and the production of parts that are 100 percent defect and issue free. Click here to request a free quote now and submit your design for a free evaluation and contact us on how to get started on your next project.