The Top 8 Injection Moulding Materials: Choosing the Right Material for your Mould - HOPO Mould

We are frequently asked which plastic injection molding material is best for specific projects. However, there isn't a single answer to this question. The optimal resin depends on your unique needs and circumstances. Fortunately, there are thousands of plastic injection molding materials available, each with similar yet distinct properties, giving you many possible options.

When selecting a plastic, the primary consideration is the part’s function and the physical environment it will encounter. This means assessing which injection molding material can withstand environmental factors such as temperature changes, moisture, chemical exposure, UV light, among others. Additionally, you need to evaluate the material’s strength, durability, flexibility, color, and cost. To assist you in narrowing down your choices, we will outline the characteristics of the ten most commonly used plastic injection molding materials at HOPO Mould.

Nylon (PA)

Nylon is frequently used for manufacturing robust mechanical parts such as bushings, gears, and bearings. It is particularly popular in the automotive industry because it is not only strong but also helps to reduce weight and production costs compared to metal counterparts. However, it is important to note that nylon tends to absorb water, making it less suitable for marine applications. Nylon is also referred to by its chemical name, PA (Polyamide).

Acrylic

A variety of colored acrylic tubes showcases the cosmetic appeal of this popular clear plastic resin. We use acrylic to create transparent parts such as windows, view screens, and lighting equipment. It is often chosen as a glass alternative due to its high tensile strength and resistance to weather and scratches. Acrylic readily accepts dyes and colorants, enabling a wide range of aesthetic effects. Besides its optical and transparent properties, acrylic is odorless, tasteless, and free of Bisphenol A (BPA), a harmful organic compound, making it safe for food storage.

Polycarbonate (PC)

A decorative collection of polycarbonate CD discs demonstrates the material's versatility. Polycarbonate is another clear injection molding resin known for its excellent optical properties and extreme durability. This amorphous thermoplastic allows for precise dimensional control due to its predictable and uniform mold shrinkage. We opt for polycarbonate when a significantly stronger material than acrylic is required. However, keep in mind that for producing optically clear plastic parts, the mold tool must be highly polished, necessitating the use of a higher-grade, more expensive stainless steel. This illustrates how the choice of plastic resin can also impact the selection of mold tool material.

Acrylonitrile Butadiene Styrene (ABS)

An image of ABS computer keyboard keys illustrates a common use for this plastic. ABS resin is an opaque thermoplastic polymer and an engineering-grade plastic with numerous advantages. It is tough, has good dimensional stability, resists impacts and scratching, and is difficult to break. Its low melting temperature also makes it easy to mold. ABS is widely used in producing electronic parts such as phone adapters, keyboard keys, and wall socket plastic guards. This is because ABS is a good insulator, does not conduct electricity, and does not emit fumes when exposed to fire—important factors for developers of electrical devices.

Polypropylene (PP)

An image of a red polypropylene bottle cap highlights the live hinge detail. This thermoplastic injection molding material is extensively used in the food storage and packaging industry because it prevents chemicals from mixing with food products. Polypropylene (PP) can be washed in hot water without degrading and has high resistance to chemicals and moisture. It boasts excellent impact strength, elasticity, and toughness. Additionally, designers should note that PP is easy to recycle and, due to its flexibility, can be used to create live hinges that can be bent repeatedly without tearing.

Polyethylene (PE)

A row of four polyethylene trash bins in a municipal park illustrates a typical application for PE plastic resin. Polyethylene (PE) is a lightweight thermoplastic molding material known for its high chemical resistance, elasticity, and electrical insulating properties. Although it is not particularly strong or hard, it is inexpensive. PE is ubiquitous in consumer plastic products, including milk bottles, medicine and detergent bottles, plastic bags, and trash cans. It is also the most common injection molding resin for making toys due to its non-toxic nature and durability.

Thermoplastic Polyurethane (TPU)

A red TPU protective phone case demonstrates the material's typical use. Thermoplastic Polyurethane (TPU) is soft and elastic with excellent tensile and tear strength, making it ideal for parts requiring rubber-like elasticity. Although TPU is more expensive than other resins, it is indispensable for applications such as protective wire and cable sheaths. Additionally, TPU enhances the grip for products that need to be held securely.

Thermoplastic Rubber (TPR)

An image of a medical catheter made from TPR rubber material highlights its application. Thermoplastic Rubber (TPR) is a blend of plastic and rubber, making it easy to use in injection molding. It offers excellent chemical and weather resistance as well as high impact strength. Therefore, TPR is used in various fluid dispensers, flexible hoses, catheters, and other applications involving different liquids, including acids.

This recyclable material is found in medical catheters, suspension bushings, and headphone cables. Thermoplastic rubber is also known as thermoplastic elastomer (TPE).

About HOPO Mould

We trust this concise summary has provided insight into some prevalent types of plastic injection moulding materials, along with their characteristics and uses.

In addition to our discussion on injection molding resins, we're proud to introduce HOPO Mould's motorcycle parts mould, crafted with precision and expertise. Originating from Zhejiang, China, our brand is synonymous with quality and innovation. Our molds are custom-designed to meet your exact specifications, accommodating a range of materials including plastic, ABS, PVC, PP, PE, PMMA, Arcylic, Nylon, and more.

Our team boasts high-level designers and utilizes advanced CAD/UG-NX design software, ensuring precise mold construction. With a focus on quality management and adherence to ISO9001, ISO14001, and ISO13485 standards, we guarantee excellence in every aspect of our production process.

At HOPO Mould, customer satisfaction is paramount. We offer one-stop production and sales services, tailored to meet your specific needs. Whether you require battery car molds, electric motorcycle molds, or injection moldable plastics, we deliver on our promise of superior craftsmanship and timely delivery.

With over 100 employees and a workshop spanning approximately 14,000 square meters, we are equipped to handle projects of any scale. Our commitment to quality extends to our stringent quality control measures, ensuring that each product meets the highest standards.

Should you have any inquiries or require further assistance, our dedicated team is here to help. Contact us today to discuss your project requirements and experience the excellence of HOPO Mould firsthand.