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Engineering plastics’ features: material introduction

Engineering plastics are resins developed for industrial use. Engineering plastics’ features include high strength and heat resistance, and properties suitable for industrial applications.

First, we will define engineering plastics and explain their characteristics and classification.

Definition and Characteristics of Engineering Plastics

Engineering plastics are materials with features that offer several advantages over traditional plastics. They are lighter than metals and their characteristics tend to support mass production. Consequently, engineering plastics are often used as an intermediate material between plastics and metals, enabling lightweight designs and cost reduction.

While there is no absolute definition for these materials, there are general criteria that can serve as a guideline. Typically, resins that exhibit long-term heat resistance of over 100°C and tensile strength of 40 MPa or higher can be classified as engineering plastics.

Classification of Engineering Plastics Based on Molecular Structure

Engineering plastics are classified based on their molecular structure and applications. There are two main categories of classification: amorphous resins and crystalline resins.

Amorphous resins are characterized by their transparency, and examples in this category include polycarbonate (PC). These resins have a non-crystalline structure, which gives them their transparent properties.

On the other hand, crystalline resins have a crystalline molecular structure. Examples of this category include polyacetal (POM) and polyethylene terephthalate (PET). These resins have a more ordered molecular arrangement, which contributes to their specific properties.

The classification of Engineering plastics based on molecular structure helps in understanding their distinct characteristics and enables the selection of the most suitable material for specific applications.

Engineering plastics features: Advantages and disadvantages

Engineering plastics have many advantages, but they also have disadvantages. Let’s find out more.

Advantages

Lightweight: making them easily processable. Also this reduces the overall product’s weight.
Easy mass production: allowing the efficient manufacturing of identical shapes.
Strength: this makes them perfect for industrial applications.

Disadvantages

High material cost: this can contribute to higher production costs.
Susceptibility to degradation from UV, oils, and water: likewise most plastics, they can degrade or experience dimensional changes when exposed to UV radiation, oils, or water.

Processing and Surface Treatments commonly used

Injection Molding

The basic principles are similar to those of general-purpose plastics, but attention needs to be paid to factors such as mold wear rate and molding temperature, which may differ from general-purpose plastics.

Machining

Engineering plastics can also be subjected to machining processes, similar to general-purpose plastics. Machining may be employed for prototyping and evaluation purposes when molds are not available. Additionally, hole drilling and gear cutting are common machining operations performed for these materials.

Painting

Engineering plastics are widely used for electrical equipment enclosures, buttons, and other components, often requiring painting as a surface treatment.

Particularly Common Engineering plastics Types and their features

Polycarbonate (PC)

Polycarbonate, also known as “PC,” is a highly transparent and impact-resistant resin. It is widely used for materials requiring transparency, such as covers and optical components. However, it is not particularly resistant to chemicals.

Polyamide (PA) (Nylon)

Polyamide, also known as “nylon,” is a plastic with high mechanical strength and excellent wear resistance. It is commonly used for mechanical parts like gears and bearings. However, it has high moisture absorption, which can lead to dimensional changes in humid environments.

Polyacetal (POM)

Polyacetal, also known as “POM,” is a material with high wear resistance and a smooth surface. It is often referred to as “acetal.” It has a smooth and slippery texture, excellent sliding properties, and wear resistance. It is frequently used as a material for gears, bearings, and resin springs. It has an opaque appearance and is generally milky white in color.

Modified Polyphenylene Ether (m-PPE)

Modified Polyphenylene Ether combines excellent mechanical strength with lightness. It is often used for the housing of electrical devices. However, it is not resistant to solvents and certain chemicals.

Polybutylene Terephthalate (PBT)

Polybutylene Terephthalate is known for its high electrical insulation properties. It has good sliding characteristics and a smooth surface. Therefore, it is used in components for electrical equipment and automotive electrical parts. However, it is prone to degradation due to hydrolysis.

Engineering plastics with meviy

meviy service handles raw material resins of short pellet in a range from 10mm to 400mm, the long pellet in a range from 10mm to 600mm, and thickness ranging from 5mm to 60mm.

Please note that there may be some exceptions for certain materials, so we recommend trying “meviy” our free quotation service if you have any concerns.