Material Matters: Explore the Diverse World of Plastics Used in Injection Molding

Unveiling the Building Blocks: Materials in Injection Molding

When it comes to the realm of injection molding, the choice of material is a critical step that might make or break the success of a product. From everyday items like water bottles and food containers to highly specialized parts in the automotive or medical industries, the variety of materials used in injection molding is as diverse as the applications themselves. Understanding the properties and applications of different materials is crucial in making an informed decision. In this guide, we will walk you through an array of materials commonly used in injection molding, shedding light on their characteristics and uses. Whether you’re a seasoned engineer or an aspiring inventor, this treasure trove of knowledge is designed to arm you with the insights needed to select the perfect material for your next injection molding project.

PP (Polypropylene)

Polypropylene is a versatile polymer used in various injection molding applications due to its high chemical resistance, elasticity, and toughness. It is commonly used for automotive parts, containers, packaging, and consumer goods. PP is known for its fatigue resistance and has a relatively high melting point among other plastics, making it suitable for high-temperature applications.

PE (Polyethylene)

Polyethylene is widely used in injection molding as it is lightweight, durable and has good chemical resistance. It comes in several densities; LDPE (low density) is often used for containers and packaging while HDPE (high density) is used in more robust applications such as pipes, fuel tanks, and automotive parts. PE is renowned for its impact resistance and is easy to process.

Polyamide (Nylon)

Nylon is a family of synthetic polymers known for its high strength, temperature resilience, and chemical resistance. It is frequently used in the automotive industry for parts such as gears and bushings, as well as everyday items like zippers. Its low coefficient of friction makes it ideal for moving parts.

ABS (Acrylonitrile Butadiene Styrene)

ABS combines the strength of acrylonitrile and styrene polymers with the toughness of polybutadiene rubber. It is widely used for making robust, impact-resistant products and is a popular material for consumer electronics, automotive parts, and LEGO toys. It has an excellent combination of toughness and rigidity.

POM (Polyoxymethylene)

Often known by its brand name Delrin, POM is used for its high stiffness, low friction, and excellent dimensional stability. It’s popular in precision parts requiring high rigidity, including gears, bearings, and fasteners. POM also maintains its properties in moist environments.

ASA (Acrylonitrile Styrene Acrylate)

ASA is known for its high weather resistance and is often used in outdoor applications where UV resistance is vital. It shares many of ABS’s properties but surpasses it in UV resistance and is used in automotive exterior parts, garden equipment, and exterior building applications.

PC (Polycarbonate)

Polycarbonate is known for its strength and durability combined with transparency. It is used in products that require transparency and impact resistance, such as eyewear lenses, bullet-proof glass, and compact discs. PC can withstand high temperatures and is also used in automotive, electronics, and construction.

TPU (Thermoplastic Polyurethane)

TPU is highly elastic and flexible. This material is abrasion-resistant and can be stretched at room temperature without breaking. It’s used for a variety of applications including automotive instrument panels, caster wheels, power tools, sporting goods, medical devices, and consumer electronics.

TPE (Thermoplastic Elastomer)

TPEs are a class of copolymers that are elastic and melt-processable. They are used where traditional rubbers would be used but provide an advantage in processing. Common applications include seals, gaskets, grip handles, and soft-touch over-molding.

PS (Polystyrene)

Polystyrene is known for its ability to produce smooth surfaces and fine details, with good electrical insulating properties. It’s often used for disposable cutlery, plastic models, and casing for appliances. PS can be rigid or foamed. General purpose PS is clear, hard and brittle.

PET (Polyester)

Polyethylene terephthalate (PET) is strong and impact-resistant. Often used in food packaging and beverage bottles. It’s also used for making mechanical parts, food containers, and other packaging applications due to its strong chemical resistance and high strength properties.

PMMA (Acrylic)

Often known as Acrylic or by trademarks like Plexiglas, PMMA is a transparent thermoplastic often used as a lightweight or shatter-resistant alternative to glass. It is used in light covers, picture frames, and general-purpose sheeting.

Resins filled with glass, minerals, carbon fiber

Adding fillers like glass fibers, minerals, or carbon fibers to resins can greatly enhance their properties. Glass fiber increases strength and stiffness but can make the material brittle. Mineral fillers can increase stiffness and lower the cost. Carbon fiber can greatly increase stiffness and strength, and reduce weight, and is used in high-performance applications.


We do it all in-house

Have you conceptualized a groundbreaking invention and are now wondering how to transform it into a tangible product? Delaney Manufacturing, an industry stalwart with over 50 years of experience in plastic parts manufacturing, is your ultimate partner in navigating this exciting journey. This step-by-step guide will empower inventors like you to harness Delaney Manufacturing’s expertise in plastic injection molding and an array of other services to breathe life into your inventions.

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