All You Need To Know About Polypropylene

By admin 1 | 1 March, 2024 |

1.WHAT IS POLYPROPYLENE?

Why is Polypropylene so highly applicable? What are the characteristics of this material? Does polypropylene have any advantages or disadvantages in production and application?… Let’s find out through this post.

1.1. Definition

Polypropylene, also known as PP, is a thermoplastic widely used in the production of packaging, yarn, and products for the manufacturing industry. Polypropylene can be found a lot in life. Products such as food containers, plastic spoons, plates, cups, syringes… are all made from Polypropylene.

Polypropylene material has high stiffness and mechanical strength. Polypropylene has many types, but the most common that can be seen in daily life are Propylene homopolymer (or PPH) and Polypropylene copolymer (or PPC).

Copolymers: Copolymers are divided into two

Propylene random copolymer: It has ethylene. Suitable for applications requiring transparency and for products with high appearance requirements)
Propylene block copolymer: Contains higher ethylene content. Suitable for applications requiring high durability.

Homopolymers: Contains propylene monomers. The main applications of this group are plastic packaging, pipes, woven, electrical appliances…

2. DIFFERENCE BETWEEN POLYPROPYLENE HOMOPOLYMER AND POLYPROPYLENE COPOLYMER

Produced through polymerization, it can be easily seen that Propylene homopolymer is more durable, harder and stronger. Combined with its weldability and chemical resistance capabilities, it is a popular choice as a material in many corrosion-resistant structures.

In contrast, Polypropylene copolymer has better durability and impact resistance. It is harder and more durable than propylene homopolymer. Generally, it tends to have better stress cracking resistance and lower temperature toughness than homopolymer.


Propylene Homopolymer	Polypropylene Copolymer

3. BASIC CHARACTERISTICS OF PP MATERIAL

The basic characteristics of Polypropylene can be mentioned are:

Transparent, colorless, odorless, non-toxic
Heat resistance: the melting temperature of Polypropylene is approximately 130 – 1160°C.
High mechanical properties
Has waterproof properties against grease, O2, and steam
Has better heat resistance and is harder than PE
High gloss, poor adhesion

4. PROS AND CONS OF POLYPROPYLENE

Like other materials, Polypropylene has great advantages and is convenient for certain applications. However, it also has limitations when used as a production material

4.1. Pros of Polypropylene:

PP is reasonably priced and widely available, easy to purchase
PP is durable, and difficult to deform when subjected to force
High waterproof ability makes it very convenient in packaging and storage applications
Has a lightweight ratio, with a molecular density of about 0.895 to 0.92g/cm³
Safe because it is non-toxic, and can be used in both medicine and daily life

4.2. Cons of Polypropylene:

Having a high coefficient of thermal expansion, PP is difficult to apply to applications requiring high heat resistance
Easily degraded by the effects of ultraviolet rays, limiting application to outdoor products
Due to its poor bonding properties, PP is a difficult material to paint. To color the final product, pigment or color masterbatch must be used during processing when the PP is in melted form.
Products from PP are susceptible to fire when exposed to high temperatures and are easily affected by oxidation, leading to reduced lifespan
It is difficult to decompose in the natural environment, causing pollution.

5. APPLICATIONS OF POLYPROPYLENE

With the above characteristics, it can be seen that PP material has high heat resistance and safety, which is why PP is used a lot in the production of household and industrial products.

For the food industry: PP is widely used in food packaging production. Typical products include Cutleries, food boxes, plastic trays, cups…
For the furniture industry: Products such as plastic flooring also use PP material.
For the consumer industry: Because it is non-toxic and highly safe, polypropylene is used to produce water bottles and baby bottles.
For the health industry: Because of its high chemical resistance and antibacterial properties, polypropylene is used to produce medical products such as syringes, and medicine boxes…
For agriculture: polypropylene is an indispensable material for producing fibers to create PP woven packaging for agricultural products.
For the electronics industry: polypropylene has extremely good electrical insulating properties. Therefore, it is often chosen as a raw material for electronic component manufacturing applications
…

6. IS POLYPROPYLENE RECYCLABLE?

An important question for those who care about the environment is the recyclability of polypropylene. Because polypropylene material is widely used to produce disposable products such as cutleries, food boxes, cups, syringes… so it would be a waste if polypropylene cannot be recycled especially when plastic waste in general and PP resin waste in particular are very difficult to decompose under natural environmental conditions. Fortunately, polypropylene is arecyclable resin. This can reduce the amount of plastic waste in the environment and reduce pressure on natural resources.

The polypropylene recycling process includes collection and cleaning steps. After being shredded, the plastic will be put into a melting furnace because recycling polypropylene requires high temperatures, above 250°C to remove impurities and contaminants. From here, recycled PP resin pellets will be created.

Recycled PP plastic will still retain its flexibility and durability. It is a valuable source of materials for industry. Although there will be aesthetic limitations such as darker colors. However, in recent years, environmentally friendly products made from recycled PP have become very popular. Typical products include water bottles, environmentally friendly bags,…

7. SUMMARY

Polypropylene is an affordable, readily available material. Has outstanding features, easily meeting the needs of businesses thanks to its high durability, flexibility, and safety. Although it is almost impossible to biodegrade and takes about 20-30 years to decompose, Polypropylene is recyclable if used well. The recyclability of polypropylene reduces environmental pollution so it is completely recyclable. Can compete with other plastic materials.