Which Type of Plastic Bag is the Strongest?

Which Type of Plastic Bag is the Strongest?

There are many types of plastic bags (poly bags), but not all have the same strength capabilities. The type of plastic bag that is the strongest will depend on the way the plastic is made.

In fact, different types of poly bags are developed just for their strength properties. The strongest type of plastic bag is made of HDPE, or high density polyethylene. Changes to the material that determine thickness and strength occur during the polymerization process. Let’s break this down a bit further.

What Determines Plastic Bag Strength?

Plastic bag strength is established by the way the ethylene reacts during the polymerization process. To make polyethylene, small molecules of the ethylene bind together to form a chain of molecules, called a polymer. From this principal chain, branches can start to form. The more branches that form, the thinner and less dense the resulting polyethylene. To make a denser, sturdier polyethylene, fewer branches have to form.

For example, if the main polymer chain is relatively straight with few branches, it is called High Density Polyethylene. HDPE is made of tightly packed molecules that not only make it more dense, but also less flexible. It can be used to make plastic bags that are stronger and more durable than lower density plastics.

If the polymer chain has many branches that form along the main strand, it might be MDPE or LDPE. Medium density polyethylene and low density polyethylene are more flexible than HDPE and also have a lesser resistance.

How Can You Tell Which Type of Plastic Bag is the Strongest?

The strength of a plastic bag is determined by its material and thickness. We already know that the material HDPE produces the strongest plastic bags, but what about thickness? Thicker bags are typically stronger than thinner bags of the same material. To determine the thickness of a plastic bag, or its gauge, you need to find its mil score

Mil is a measurement used to express plastic bag thickness. A mil is equal to a thousandth of an inch. To get an idea of how bag thickness is expressed in mils, refer to these common examples of types of plastic bags:

  • Common grocery store bag: ½ mil
  • Bread bag: 1.5 mils
  • Clothing store shopping bag: 2 mils
  • Packaging for screws or nails: 4 mils
  • Extreme puncture resistance for industrial parts that are sharp or heavy: 6 mils

Which Type of Plastic Bag Offers the Best Quality?

Bag strength and thickness aren’t the only determining factor of a good quality plastic bag. HDPE, MDPE, and LDPE all have useful applications as plastic bags. The application will determine which bag qualities are essential, such as durability, clarity, and ease of opening. Let’s take a closer look at these qualities to help you understand the different advantages these qualities of poly bags offer. 

Poly Bag Durability

Bag durability doesn’t just refer to the tensile strength of the plastic. The durability of a poly bag could also mean its resistance to chemical corrosion, punctures, or regular wear and tear.

Poly Bag Clarity

Bag clarity is important in many applications where product visibility is key. For example, for many food grade poly bags, customers need to be able to see the enclosed item clearly to check for quality. A translucent or opaque bag would not serve this purpose. 

Poly Bag Ease of Opening

If you’re just looking for which plastic bag is the strongest, you might not want a bag that is easy to open, but in some applications, this is a good quality to have. Bags containing small parts like screws and nails need to keep the items together, and be strong enough to not spill the items, but also need to be easy to tear to access what’s inside.

Which Type of Plastic Bag is Best for You?

When shopping for which type of plastic bag is the strongest, consider the other needs your application might have. If strength is the most important quality, then an HDPE poly bag at a high mil strength will likely be the best type of plastic bag for your needs. However, if you’re looking for a strong plastic bag with other qualities, consider other types of poly bags that may work just as well. 

If you’re still unsure which type of poly bag is right for your application, contact A-Pac Manufacturing. We manufacture the highest-quality poly bags, with no minimum order and 2-3 week lead times. Give our team a call for more information.

How to Choose the Right Poly Bag to fit your needs cta

Message to Our Customers About COVID-19

In light of the COVID-19 pandemic, we wanted to let you know that A-Pac Manufacturing will continue to take and ship orders, and we don’t foresee any supply chain disruptions at this time.

We have also taken the following measures to ensure the health and safety of our employees: Only essential staff will be working on site, and employees who are able to work from home are doing so.

If you have any questions at this time, please send us a message or call (800) 272-2634.

We wish you and all your loved ones health and safety during this unprecedented time.

Merry Christmas and Happy New Year!

No matter how you celebrate the holidays, it’s a great time to slow down and reflect on the blessings you’ve received over the past year.

We’re truly thankful for customers like you and feel very fortunate that you’ve chosen us to be your supplier. Your impact is felt throughout the company and in all of our lives.

In the spirit of this Christmas season, we hope you’ll pass on our blessings to those closest to you.

Wishing you and all your loved ones health, happiness, and prosperity now and in the New Year.

Happy Thanksgiving!

This time of year gives us a great opportunity to thank you for your business and wish you a very Happy Thanksgiving. We hope you’re able to take some time to enjoy the holiday with family and friends and give thanks for the many blessings in your lives.

A-Pac will be closed November 23rd and 24th so our employees can spend the holiday with their own family and friends, but we will all be back in the office November 27th. If there’s anything you need at this time or after the Thanksgiving holiday, just let us know.

Happy Thanksgiving!

Resin Outlook – Fall 2019

Just a quick update on resin pricing as we head out of summer and into fall.

Many major resin suppliers successfully implemented a $.03/lb increase in September, and there are already rumblings about additional increases for October and November.

As a result, we’ve heard many of our competitors are already raising prices, so we wanted to assure you our resin supply is strong and we have no intention of raising our customers’ prices in the short term. With how volatile the resin markets can be, we feel it’s always better to see how things shake out over the course of a few months before making any decisions about pricing.

If you have any questions about resin pricing or anything else at all, please email us or just give us a call at (800) 272-2634.

Thank you for your continued business, and we hope to hear from you soon.

Resin Pricing, Lead Times, and Holiday Hours – Summer 2019

It’s been a few months since our last update, so we thought it would be a good time to touch base with you.

Many major resin suppliers implemented a $.03/lb increase in May, and they’re already talking about more increases in June and July. It’s too soon to know if those will go through as well, but right now we hope to keep your prices steady. If the market changes drastically, we’ll always reevaluate, but our main goal is your customer satisfaction and a consistent ordering experience during minor market fluctuations.

As for lead times, we’re currently looking at 2 to 3 weeks for all bag types. The summer is usually quite busy for us, so if you know you have an order coming up, now would be a good time to let us know so we can schedule appropriately.

We also wanted to make you aware that we will be closed July 4 and July 5 so our employees can enjoy a much-deserved extended weekend. If you have placed or will need to place an order that requires delivery around that time, please note that it will likely ship before or after those days.

If you have any questions about this update, please email us or just give us a call at (800) 272-2634.

Thank you for your continued business, and we hope to hear from you soon.