Can we reuse PP 5 plastic (Polypropylene)?

We all are aware of plastic identification numbers. There are generally 7 types of plastics that we can see in our daily life in almost every use case. And PP/polypropylene is one of the most common plastics that we can see everywhere around us. We identify PP/polypropylene as the #5 plastic category. You may have heard that only 3% of the PP #5 plastic applications can be recycled but it is strongly recommended to reuse PP products! PP 5 plastic containers are usually safe to reuse, and PP is one of the safest plastic types among all the seven. In this article, we will learn if PP (Polypropylene) 5 plastics are really reusable or not!

Generally, PP (Polypropylene) number 5 plastic-made products are reusable because of their excellent properties of the integral hinge, good chemical and heat resistance, and durable structure. Sometimes we might find it hard to reuse some particular shapes as we can find its use cases everywhere, from the medical industry to manufacturing tiffin boxes. But it is easy to reuse the containers made of PP 5 plastics, and sometimes we can even repurpose them in other use cases.

Next, we’ll try to know Polypropylene/ PP 5 plastic more in detail, so when we discuss the ideas to reuse pp 5 plastics, it will be easier to understand for you.

Symbols used in this article: To denote Polypropele plastic, we will use PP 5 plastic throughout the article or sometimes interchangeably.

Properties of PP 5 plastic

We get PP 5 plastic from the polymerization of propylene. PP 5 plastic has almost the same properties as polyethylene, but PP is more rigid and has better heat and chemical resistance.

The Chemical formula of Polypropylene is (C3H6)n

1. Thermoplastic Property

Polypropylene/ PP 5 plastic is a thermoplastic polymer. That means we can melt the product of PP 5 and then reuse it in a different form. But unfortunately, we can’t reuse pp 5 plastic in a similar way at home. It needs industrial technologies.

2. Thermal Expansion

The thermal expansion of PP 5 is significantly large but not as good as polyethylene.

3. Low density

PP 5 has a relatively low density of around 0.905 g/cm3, which is less than most polyethylenes.

4. Linear Hydrocarbon polymer

PP 5 has a long continuous carbon-carbon chain without any branched chains, unlike branched polymers where you can see a branched polymer chain attached to the primary chain.

5. Reactions at room temperature

At room temperature, PP 5 plastic is usually non-reactive and resistant to fats, oils, and most organic solvents. That is why you can see its use in making food boxes and even microwave containers. But remember, this property will significantly change at high temperatures and can be reactive to many chemicals.

6. Resistant to moisture

PP 5 plastic has great dimensional and chemical stability in high moisture, which is why it is popular to make food containers.

7. Melting Point

The melting point of PP 5 plastic is around 160°C (320°F). We can safely use the products of pp 5 plastic at room temperature, maintaining all the excellent properties.

Applications of PP 5 plastic

As I mentioned, we can see PP 5 plastic use cases almost everywhere. In this section, we’ll take a deep dive and get to know all of its possible applications in the present time.

1. Medical Industry

We can see PP 5 plastic’s extensive use in medical appliances like funnels, syringes, fibers in masks, test tubes, trays, and many more.

2. Consumer Products

PP 5 plastic is everywhere. Just pause reading and look around you. PP 5 plastic is used to make toys, furniture like chairs and tables, or even study desks, housewares, etc.

Even your kitchen is also filled with PP products. Usually, trays, spoons, microwave bowls, tiffin boxes, food containers, etc., are some everyday use cases of PP 5 plastic.

3. Rigid packaging for strain-sensitive products

Many products are strain sensitive, and those products need rigid packaging to reach the consumer safely without any damage. To make such cover or packaging, we use pp 5 plastic. In the old days, those DVD boxes used to be PP-made.

4. Plumbing and electricity cables

We don’t see PP 5 plastics in plumbing that extensively, but their uses are critical in some specific situations. As we know, PP is highly non-reactive in normal temperatures, so we often see PP pipes used in the drainage system.

Also, many manufacturers use PP to make the outer layer of electric cables.

5. Textile industry

Mostly we can see PP use cases in carpets and sometimes to make carpet backing. Also, I have seen some manufacturers use PP fabric to make raincoats.

Why is it possible to reuse pp 5 plastic?

The answer is simple! For the following characteristics, we can reuse PP 5 plastic: Safety, Durability, Thermoplastic Property, and Non-reactive properties in normal temperatures.

Now, at home, we can mostly try repurposing to reuse PP5 plastic. We’ll discuss some of the ways in the next section. However, we can’t make use of its thermoplastic property to reuse it at home, and it will need the proper engineering and technology that manufacturers have.

How to reuse PP5 plastic

Basically, there are three ways to reuse. 1. Changing shapes 2. Repurpose 3. Reuse after cleaning.

1. Changing Shapes

Because of PP 5 plastic’s excellent thermoplastic property, we can reshape the PP products to make new products with the process of molding. Unfortunately, we can’t try this at home. We need to melt the PP to bring it into its liquid state and then reshape them using molding!

2. Repurpose

We can see PP plastics in different shapes everywhere. So sometimes, you need to scratch your head to find repurposing ideas. But the most common idea that I can think of is repurposing the containers. I had some old pp 5 plastic-made tiffin boxes that I don’t use anymore for food, and now I have repurposed those boxes to store my color pencils. Also, I remember how we turned 20 bottle caps into home decor. So yeah, as you go creative, you’ll find more ideas. Just don’t throw away pp containers. You can definitely think of some ideas and try to repurpose them.

3. Reuse

I guess you remember I mentioned PP is non-reactive at room temperature. You can reuse PP products just after cleaning. Yes, it is that easy to reuse PP products. You can safely wash these products with soap, and they won’t chemically react at room temperature. But for the microwave containers, some reports say that it is not too safe to use those containers for so long. I would advise avoiding any high-temperature conditions. 

PP 5 plastic’s Environmental impact

PP 5 plastic is not biodegradable. So definitely, unorganized disposal has a huge risk to the environment. Never throw away these PP products just anywhere. Reach out to the local recycling center or use blue dustbins. Those blue dustbins are for non-biodegradable wastes.

But these PP products are relatively safe cause you can reuse them multiple times. And that’s why we made this article; just feel free to reuse them as much as possible or try repurposing them. Just ensure you are not heating it up at a very high temperature, and its melting point is around 160 degrees Celcius.