A simple guide to buying plastic bottles

Since there are tons of plastic bottles available in the market, the wide variety makes it much more difficult to buy the best one for your needs. They come in different sizes and shapes, and each one has its own set of unique features. If you want to know all the different things that need to be considered in order to make the best decision, read on.

What are plastic bottles?

A plastic container is a jar constructed of either high-density or low-density plastic. Plastic containers are commonly used to store liquids, such as water, soft drinks, motor oil, cooking oil, medicine, cleaners, milk, and ink.

The size of these units range from extremely small containers to huge carboys. These containers may have molded or molded handles for easy gripping. The biggest advantage of plastic jars over glass containers is that they offer protection against breakage during the manufacturing process and transportation.

How are they made?

The manufacture of plastic containers occurs in multiple stages. Commonly, the plastic jugs used to contain consumable water and different beverages are made of polyethylene terephthalate (PET), since the material is solid and light.

Polyethylene (PE) has a high thickness, which is why it is used to make plastic containers that do not bend, such as cleaning bottles and squeeze bottles. Polypropylene (PP) is used for pill bottles etc.

Polycarbonate (PC) is used for refillable water bottles and similar reusable containers. To understand the manufacturing process, it is helpful to initially understand the compositions of PET, PE, PP and PC and how these materials affect the manufacture of plastic bottles.

The process

The main phase of a regular 2-stage Reheat Blowing Machine (RBM) bottle production process is known as injection molding. Plastic granules are plasticized in the barrel of an injection forming machine where the plastic is softened by heat. The plastic is then infused into multi-cavity molds where it forms into long, thin tubes.

When the bottle (or, in consistent manufacturing, the bottles) has cooled down to a certain shape, it is removed from the mold. The plastic bottles are then prepared for transportation or filling.

Types of plastic materials used

Before you go ahead and make a decision, we suggest you consider the types of materials used to make plastic bottles. Below are some of the common materials that manufacturers use for this purpose.

PET (polyethylene terephthalate)

Polyethylene terephthalate is a thermoplastic polymer that can be opaque or transparent depending on the composition of the material. Also, with most plastics, PET is created from petroleum hydrocarbons. To produce plastic bottles, PET is first polymerized to form long molecular chains.

When the plastic itself has been manufactured, the bottle manufacturing procedure can begin. To ensure that PET is suitable for use, several post-manufacturing tests are carried out to ensure that the containers are impermeable to carbon dioxide.

Apart from this, different variables such as transparency, gloss, tear strength, thickness and pressure resistance are also controlled.

Low and high density polyethylene

Another thermoplastic, polyethylene, is used to assemble blow molded milk and water containers, cleanser bottles, ketchup bottles, etc. Both LDPE and HDPE can be thermoformed, blown, infused, etc. HDPE is used for some types of plastic jars as it has higher stiffness.

Polypropylene

Polypropylene is a typically opaque, low-density polymer with excellent thermoforming. In the case of bottles, it competes very well with polyethylene and can be made transparent for see-through applications. Polypropylene cannot match the optical clarity of polymers, eg polycarbonate. However, it does a great job.

polycarbonate

It is an expensive material compared to other polymers for making jars. Therefore, the application of this material is restricted to very good quality reusable containers, such as baby bottles or those found in water dispensers or in laboratories.

The material has excellent optical properties and quality, making it suitable for bottles that must display their substance with the transparency of glass but must have the ability to withstand routine mishandling.

Important things to consider when buying plastic bottles

When choosing plastic jars, there are a couple of areas you need to focus on. This is particularly important for bottles that are used to store edible things. You need to ensure that your bottles are sturdy and safe for your items.

Here are some significant tips to choose the best bottle according to your need.

BPA Free – Bisphenol A, or BPA, is an industrial chemical used to make plastic items. This chemical has been used since the 1960s. However, recent research has indicated that the substance can leach into foods and liquids contained in affected plastics.

Thoroughly clean: Make sure to check with the seller that the containers and jars are properly sterilized, since the bottles go through different processes and places before finishing with you.

Personal inspection: Before purchasing, make sure the plastic bottle has no areas of mildew marks or any other physical problems.

Container sizes: Plastic jars come in a variety of sizes ranging from as small as 30ml to mid-range sizes of 500ml and 1000ml. So make sure you get the right size according to what will be stored in them. For example, storing 1 glass of juice in a 1000ml container might not work the best. Therefore, it can be recommended to get a container of 300 ml.

Types of caps: Plastic bottles and jars come with a variety of caps. Mainly of these include flip tops, twist caps and spray caps. Other containers can also be compressible. All these lids are to store different products in them. For example, a dense liquid may be better stored in a squeezable container as it will be easier to handle.

Food to go

So, you’re ready to buy a plastic bottle, but choosing the right bottle shape and size can be overwhelming. There are a lot of factors to consider and not every container is right for what you need it for. Therefore, we suggest that you consider this guide before placing your order.