Hillside Design News -Looking at the properties of plastics

There are literally thousands of different plastics and plastic alloys, with more being added to the list monthly. To start the selection process it is very useful to understand the characteristics of the most common plastics families. Below are a selection of the plastics you will encounter in products you use every day.

Generalised qualities of some plastics

Acrylonitrile butadiene styrene (ABS)

A polymer of styrene (providing a shiny, impervious surface), polybutadiene (for rubbery toughness), and nitrile monomers (which bind the chains together for additional strength), ABS is commonly used for lightweight injection mouldings such as remote controls, automotive trim, and toys.

Poor UV-resistance
Poor stress cracking resistance
Low water absorption
Good resistance for diluted acids and bases
Good oil resistance
Good scratch resistance
High surface hardness
Good impact strength

Polyethylene (PE)

A semi-crystalline thermoplastic with a high degree of toughness and very good chemical resistance. When compared to other plastics, it exhibits low mechanical strength and temperature resistance, however this can be improved by using grades with higher molecular weights. Primarily used in packaging, it is also used in varying grades for piping, chopping boards and even knee replacements.

Low density compared to other materials
High impact resistance, even at low temperatures
Good resistance to wear
Minimal moisture absorption
Excellent chemical resistance
High corrosion resistance
Non-stick

Polypropylene (PP)

Another semi-crystalline thermoplastic, which resembles HDPE, but exhibits higher strength, rigidity and hardness. PP is, however, sensitive to impact at temperatures below freezing point. The chemical resistance is comparable to PE. PP is widely used in applications from flip-top bottle caps, furniture, rebar supports, and alternatives to laboratory glassware.

Low density compared to other materials
Minimal moisture absorption
Excellent chemical resistance, even to solvents (but this means labels may not adhere to it)
Highly corrosion resistant
Relatively high superficial hardness

Nylon 6

Although Nylon was originally developed as an alternative to silk, modern grades of nylon are extremely versatile and can be used in engineering applications such as gears, engine fittings, and even toothbrush bristles. Other grades of Nylon (Nylon 12) are used in cosmetics and sports apparel.

Balanced toughness and rigidity
Capacity for hardness level adjustment
Extremely high impact strength, also down to -40°C
Good abrasion and wear resistance
High energy and shock absorption
No brittle fractures under pressure or impact loads
Extreme wall thickness variations can be realized in the moulded component
Ready integration of inserts and reinforcement materials and fillers

For help in readying your design for manufacture, and ensuring that your materials selections are optimal, contact Hillside Product Design and discuss your project with us.

If you’ve got an idea you want to take to market, we will assist you through your journey. Even the most accomplished will require assistance which is where Hillside Product Design’s expertise is invaluable. We work closely with all our clients to ensure they have all the support they need throughout the product development process.