The 10 Most Popular Injection Molding Materials

It is often complex to know about the most popular injection molding materials used for different projects. And to be honest there is no one certain answer and option available to saturate the question.

And for your concern, the best material is to fulfill the circumstances of your work. And there are a number of resins available in the market to use in your injection molding project. So having proper knowledge about your project requirement will help you to choose the best resin material. Let's discuss the most popular injection molding materials and their advantages - but firstly explain these ten.

1. acrylic (PMMA)

2. acrylonitrile butadiene styrene (ABS)

3. nylon polyamide (PA)

4. polycarbonate (PC)

5. polyethylene (PE)

6. polyoxymethylene (POM)

7. polypropylene (PP)

8. polystyrene (PS)

9. thermoplastic elastomer (TPE)

10. thermoplastic polyurethane (TPU)

For each plastic, the following materials explain what you need to know.

Acrylic (PMMA)

Poly is known as acrylic or PMMA, as it's strong and lightweight and shatter-resistant. As the thermoplastic makes it transparent and optical clear that's the reason light can pass through it. It has high tensile strength that's why it can bear heavy load, and can resist weather as well as sunlight and become perfect for outdoor purposes.

It would not absorb odor and when contact with water it doesn't release Bisphenol A which has a serious effect on human health and is usually found in many low quality plastics.

Advantages

● Weather-resistant

● Bear heavy load

● high tensile strength

● Health friendly

PMMA Grades, Applications

It has roots in various industries like…

● used in windows,

● greenhouses,

● solar panels,

● bathroom enclosures,

● transparent components

● architectural

● lighting applications

General-purpose acrylics are considered least expensive as compared to Sign-grade that have capacity to stay strong more than 10 times. Marine-grade acrylic is commonly used in boat building, etc.

Acrylonitrile Butadiene Styrene (ABS)

Acrylonitrile Butadiene Styrene is engineering-grade with molding capacity. ABS with low melting point support the use of colorants and are available in different surface finishes and textures. It is best known for its impact resistance and strength.

It is tough, least expensive, and offers good resistance against fire, oils, heat, alkalis, and acids. Owing to styrene content it gives attractive and shiny finish to molding parts along butadiene which offers extra toughness even in low temperature. It is not recommended in outdoor activities as it has no resistance against sunlight and weather.

Advantages

● High toughness

● Least expensive

● Good resistance properties

● Attractive and shiny finish

ABS Grades, Applications

ABS can be combined with glass fillers to add strength and polycarbonate for low-temperature. We offer filled and unfilled ABS plastic. It is used in various industries.

● electronic components

● and with keyboard keys,

● protective headgear,

● plastic wall plates for electrical outlets,

● automotive components: dashboards, wheels covers, auto body parts, etc.

● consumer goods,

● sport equipment,

● and industrial fittings

Nylon Polyamide (PA)

Nylon Polyamide (PA) can be neutral or synthetic because it is a large group of materials. Nylon is a type of polyamide that is always synthetic but in the injection molding process it can be difficult to manage it as it is prone to shrinkage along with inadequate filling.

Its strength can be measured as it is used in strong mechanical parts like gears, slides, bearings, etc. It is the best option for snap-fit closures and kinetic parts, threaded inserts, jigs and fixtures. Nylon comes in different grades 66, 11, 12, and 46. And every grade has different mechanical properties and is filled with glass.

Advantages

● high abrasion resistance

● good fatigue resistance,

● noise dampening properties.

● high heat resistance

● Highly toughness

● low coefficient of friction

Nylon Applications, Grades

Nylon is usually used in mechanical parts to make them more strong like in bearings, slides and gears, etc. It has four types of grades and each comes with versatile properties.

● strong mechanical parts: bearings, bushings, gears, and slides

● casings and snap-fit closures

● kinetic pats

● threaded inserts

● jigs and fixtures

● toothbrushes

● wheels to medical implants

● electrical connectors

Polycarbonate (PC)

It is strong and tough plastic and is transparent. It is like PMMA but has unique specifications that cover a wide range of temperatures. During pigmentation, it does not fade its color rather it maintains its color shine along strength.

Its strength can be measured that it is 250 times more durable and stronger than glass. The PC offers precise dimensional control and is lightweight.

Advantages

● Lightweight

● precise dimensional control

● 250 times stronger than glass

● excellent optical properties

● support light transmission

PC Applications, Grades

Polycarbonate is usually used for diffusers, machinery guards, clear tubing, etc. PC also used for silicone casting and urethane.

● machinery guards,

● clear or tinted windows,

● diffusers and light pipes for light emitting diodes (LEDs),

● in clear tubing

● silicone casting

● Urethane

Polyethylene (PE)

PE is widely used plastic in the world. It has three types…

● high density (HDPE, PEHD)

● low density (LDPE)

● polyethylene terephthalate (PET, PETE)

It is one plastic which is used according to its density because it controls and bears other materials properties. Although LDPE and HDPE both have unique properties like chemical resistance, they are quite different in terms of melting point, flexibility, and optical transparency. Designers like these materials due to their optical clarity and other properties.

Advantages

● PET, HDPE, LDPE, all are low-cost plastics

● It resist both chemicals and moisture

● LDPE is and opaque material

● LDPE, PET are as clear as glass

PE Applications, Grades

They have their uses in different industries such as…

● milk bottles (HDPE),

● plastic films (LDPE),

● water bottles (PET)

● children’s toys,

● toolboxes,

● electronic wire and cable insulators,

● medical device components.

They come in different densities where the higher numbers indicate the higher density. For instance, HDPE 500 has higher density than HDPE 300.

Polyoxymethylene (POM)

POM is also known as acetal and requires low friction, excellent dimensional stability and high stiffness. POM plastic has highly crystalline structure, white in color along naturally opaque. It has excellent rigidity with thermal stability .

Advantages

● rigidity with thermal stability

● low coefficient of friction

● low water absorption

● good chemical resistance

POM Applications, Grades

It is best for gears, conveyor belts, bearings, and pulley wheels due to low coefficient of friction.

● fasteners,

● eyeglass frames,

● parts for knives and firearms,

● lock systems,

● high-performance engineering components

POM unlike other injection molding materials comes in different grades that can be reinforced with minerals and fiberglass for its stiffness and strength. Both materials offer excellent mechanical properties.

Polypropylene (PP)

PE is widely used plastic in the world. It is one plastic which is used according to its density because it controls and bears other materials properties. It resists both chemicals and moisture.

Advantages

● good chemical resistance

● retain their shape

● high melting point

● recyclable up to four times

● Combinable with other plastic

● resistance to warping

PP Applications, Grades

● children’s toys,

● storage containers,

● sporting goods,

● packaging,

● appliances,

● power tool bodies

Grades are of crystalline polypropylene rather than regular polypro.

Polystyrene (PS)

It is known as commodity plastic with two types…

● General purpose polystyrene (GPPS)

● High impact polystyrene (HIPS)

GPPS has less dimensional stability than HIPS, the same as the crystal clear and later with opaque properties. Owing to their shrinking features both types are best for injection molding.

Advantages

● inexpensive,

● lightweight,

● resistant to moisture

● bacterial growth

PS Applications, Grades

● medical,

● optical,

● electrical

● electronic applications

● toys,

● cases,

● containers,.

● trays

Thermoplastic Elastomer (TPE)

It is best blend of plastic materials and rubber. Although it has functions like rubber yet properties of plastic. Its elasticity attracts the designer and engineer to work with it. You can recycle it more than six time.

Advantages

● can be stretched

● shorter molding cycles

● support two-shot molding

● less expensive

TPE Applications, Grades

● footwear,

● medical devices,

● auto parts,

● and pet products

● Automotive applications

● Medical applications: breathing tubes, valves, catheters, and ventilation masks.

Thermoplastic Polyurethane (TPU)

TPU unlike TPE has rubber-like elasticity. Injection molded TPU possesses a higher durometer and is replaceable with hard rubber. It is best for chemical resistance and extreme temperature.

Advantages

● resistance to abrasion ;chemicals; greases; oils; high temperatures.

● good load-bearing capacity

TPU Applications, Grades

● footwear,

● gaskets,

● caster wheels,

● and sporting goods

● electronics and medical devices

Why choose Boen for plastic injection molding?

Boen in injection molding has years of experience and a number of companies trust its services. As Boen also offers custom services to make its clients' projects successful.

We offer advanced and classy injection molding services along through information that cover all aspects be it tool making, finishing, raw material verification, part fabrication and inspection. We committed to offer you the best team services regarding injection molding of any kind. Get a free quote  and contact us today for your next project!