Nylon 6 vs. Nylon 66 What’s the Difference？

What Are These Plastic Things?

Nylon 6 and Nylon 66 are strong plastics. Many things we use every day have these plastics in them. They are both in the polyamide family. That means they are made of the same kind of stuff.

Let's look at what makes them the same and what makes them different.

How They Are Made

The way we make these plastics is not the same.

• Nylon 6 comes from one thing called caprolactam
• Nylon 66 comes from two things mixed together

This is why they act different when we use them. Think of it like how cake and cookies are both sweet treats, but they are made with different steps.

The Big Differences: A Simple Table

Where We Use Nylon 6

Nylon 6 is great for:

1. Clothes and bags that need to be soft
2. Fishing line that needs to be strong but bendy
3. Toys that might get dropped
4. 3D printing parts that don't warp

Nylon 6 is good when things need to bend but not break. It's like the plastic bags at the store - they stretch but don't tear easy.

You can see more about different types of nylon materials here.

Where We Use Nylon 66

Nylon 66 is best for:

1. Car parts that get hot (like near the engine)
2. Gears that need to be super strong
3. Tools that get used a lot
4. Electrical parts that can't change shape

Nylon 66 is good when things need to stay strong even when hot or wet. It's like the plastic handles on pots and pans - they don't melt when cooking.

For special black versions used in electronics, check out conductive nylon compounds here.

Water and Heat: Big Deal-Breakers

One of the biggest differences is how these plastics act when they get wet or hot.

Water Test

• Nylon 6: Soaks up lots of water (like a sponge)
• Nylon 66: Doesn't soak up as much (more like a plastic cup)

When Nylon 6 gets wet, it can get 30% weaker! But Nylon 66 only gets about 15% weaker when wet.

Heat Test

• Nylon 6: Gets soft at lower heat (like butter on a warm day)
• Nylon 66: Stays hard in more heat (like cheese on a warm day)

This is why car makers pick Nylon 66 for parts that get hot.

Making Things: Which Is Easier?

When we make things with these plastics:

• Nylon 6 is easier to work with
• Nylon 66 needs more careful setting up

For 3D printing:

• Nylon 6 prints with less problems
• Nylon 66 can warp and needs more drying first

Cost Matters Too!

Nylon 6 costs less money than Nylon 66. This is a big deal when making lots of things.

• Things like zippers and toothbrushes use Nylon 6
• Things like car parts that must be super strong use Nylon 66

If you want to know more about nylon 66 materials specifically, click here.

How to Pick the Right One

Ask these easy questions:

1. Will it get very hot? (Over 80°C) → Pick Nylon 66
2. Does it need to bend a lot? → Pick Nylon 6
3. Will it be in water a lot? → Pick Nylon 66
4. Is cost the most important? → Pick Nylon 6
5. Does it need to be super strong? → Pick Nylon 66

Real Life Examples

Here are some things you might know that use these plastics:

Nylon 6 Things

• Fishing line
• Toothbrush bristles
• Carpet fibers
• Zip ties

Nylon 66 Things

• Car engine parts
• Electrical plugs
• Gears in machines
• Chair wheels

Same Family, Different Jobs

Think of Nylon 6 and Nylon 66 like brothers in the same family:

• Nylon 6 is the flexible, cheaper brother who's good at many jobs
• Nylon 66 is the tough, heat-resistant brother who's good at hard jobs

Both are good! They just do different things better.

Why This Matters

Picking the right plastic saves:

• Money (don't pay for what you don't need)
• Time (using the wrong one can break)
• Safety (some jobs need the stronger one)

Final Thoughts

Both Nylon 6 and Nylon 66 are amazing plastics that make our lives better. The key is picking the right one for what you need.

• Need bendy, cheaper plastic? → Nylon 6
• Need strong, heat-proof plastic? → Nylon 66

Now you know the big differences, you can make smart choices about which nylon is best for your needs!