PET Blow Moulding – Innovations in PET Resin and Applications
Abstract
Polyethylene Terephthalate (PET) is one of the established packaging material both for food and non-food applications. These are made by ‘Injection Stretch Blow Moulding’ process and it combines good barrier properties, clarity and impact resistance. The high speed blow moulding processes have made PET containers a choice for carbonated beverage containers, dressings, edible oils, peanut butter, milk, juices and many other food/beverage products in India & abroad.
PET possesses excellent physical properties, high strength and excellent oxygen barrier and carbon dioxide barrier properties. With combination of special PET grade and heat set blowing process, PET bottles are today available with high‐temperature properties, i.e. for hot-filling of juices, ketch-up etc. The PET equipment industry has today created state of the art niche process lines for making PET performs and bottles including in-line blowing & filling, aimed at players looking for at medium to high outputs & high sustainability with advantage of cost-competitiveness.
The PET Bottlesare available in different specifications/sizes as per requirement of end-users in different sectors. These bottles are designed in compliance with innovative process technologies, so that these are very convenient to fill inmodern equipment and at cost-effective prices.
The PET bottles are available as transparent or opaque range and today ever more consumers are attracted to PET for applications like Edible Oil, milk, juices, agro-chemicals, lube oil and bulk containers for chemicals etc. These are readily available in pack sizes from 100 ml to 15 L in India and end-users are also studying possibilities for bulk PET containers (15L)for applications like Edible Oil etc. These PET sizes are well established even in neighbouring countries like Malaysia&China. There are innovations in filling technologies too, for e.g. the Liquid nitrogen dosing helps to improve the shelf life of products like oil packaged & also improves the bottle physicals.
Reliance have now developed a special barrier resin for oxygen-sensitive foods & beverages
This isa specialty PET resin‘Relpet Barrier resin B9845’ with oxygen scavenger developed to improve oxygen barrier of packages. It reduces oxygen transmission rate (OTR) by more than 150 folds vs. normal PET bottle and also for the thermoformed APET blister packages. It also improves the carbon-dioxide retention by around 50%. Barrier PET bottles are suitable for all those products which are currently more sensitive to oxygen permeation& currently packaged in glass/other materials &. Barrier PET bottles are globally used primarily for packaging of oxygen sensitive products like ketch-up, beer, juicesetc &we extended this logic to health-care in India.
PET is a fully recyclable material. It is given the recycling code of 1 inside a triangle by ASTM. The Post-consumer recycled PET (PCR PET) is used for clothing and carpet fiber &fiber-fill for stuffing articles such as pillows. Recycled PET is not used for making bottles in India, however it can be used to make new bottles for non-food products such as cleaning products.
