Initiatives to replace plastic with other alternatives have long been in play but the packaging section in the industrial sectors is now overturning the situation. Replacing plastic with single-use plastic, paper, and cotton products intended for the purpose didn’t seem to resolve the issue. The plastics industry took the opportunity and began providing undeniable options in a time where plastic is being rejected.
Plastics are strong, durable, lightweight, cost-effective, and consume fewer material resources for manufacturing in comparison to its alternatives. There are 6 different types of plastics used for packaging that possess salient features in durability, lightweight, sustainability, versatility, inexpensiveness, and most importantly, recyclability. Further discussed are the types, their properties, and their uses in applications.
The first type of resin is the High Density Polyethylene (HDPE), a safe plastic used in a wide range of products. As the name suggests, it is a high density to strength ratio resin with chemical resistance and is frequently used in packaging with unpigmented translucent and barrier properties for bottles and containers. It is used for packaging products with short life spans, household and industrial chemicals like detergents and bleach.
The pigmented HDFE packaged bottles have stress crack or shattering resistance, higher tensile strength, temperature capabilities, and versatility. We see illustrations of it for packaging bottles containing milk, water, juice, cosmetics, shampoo, and household cleaners as well as bags used for groceries and retail purchases. These products can be recycled into pens, rubbish bins, outdoor furniture, fencing, and detergent bottles.
Second on the list is Low Density Polyethylene (LDPE) that also includes Linear Low Density Polyethylene (LLDPE), which has a broad use in film application due to it’s tough, flexible and relative transparency for heat sealing. LDPE is resistant to acids, bases, and oils thus creating an excellent barrier to oxygen, water, and carbon dioxide. It provides flexibility in food packaging, lids, bottles, wires and cables, bags for dry cleaning, newspapers, bread, frozen foods, fresh produce, and household garbage and a shrink wrap and stretch film coating of it is used to coat paper cartons and hot and cold beverage cups, container lids and squeezable bottles in housing and essentials. It can be recycled to bin liners, shopping bags, floor tiles, shipping envelops, etc.
The next resin is Polyethylene Terephthalate (PET) that has a clear and optically smooth surface formula in films and bottles. PET provides a gas, water, and moisture barrier for packaging plastic beverage bottles containing water, juice, beer, mouthwash, etc., food jars for peanut butter, jelly, jam and pickles, injection moulded consumer product containers, fibers in clothing, 3D printable thermoplastics, PETG and PET strapping.
Additional qualities of PET are its high impact capability and shatter resistance that do not let the product to break easily, while its resistance to most solvents do not taint the flavor of food packages. Cleaned, recycled PET flakes and pellets are used to manufacture spinning fiber for carpet yarns, fiberfill, and geotextiles, new containers, strappings and ropes, carpet fibers, clothing, and cushion or jacket filling.
Next is Polypropylene (PP) resin that has a chemical resistance with a strong, flexible, and high melting point required for hot-fill liquids or contents. It can be moulded for extensive varieties of products and optical clarity for biaxially oriented films, and stretch blow moulded containers. With a low moisture vapor transmission and inversion or intervention towards acids, alkalis, and most solvents it helps create sterile syringes, containers for yogurts, takeout meals, deli foods, medicine bottles, bottle caps and closures. These products are later recycled and remade into brooms, auto battery cases, pallets, signal lights, and bicycle tracks.
The resin Polystyrene (PS), commonly known as Styrofoam, in rigid or foam form, is a low-density foam with a low melting point but does not conduct much heat and its insulation helps transport hot or cold products. It is used in protective packaging, foodservice packaging, bottles, and food containers and its moisture barrier supports short life products.
PS has an optical clarity for general purpose and a significant amount of stiffness in foam and rigid forms. Low density and high stiffness in foamed applications, low thermal conductivity and excellent insulation properties are found in foamed forms. Foodservice items like caps, cups, plates, meat and poultry trays, disposable plates, bowls, and cutlery, disposable razors, protective packaging, and other rigid containers like CD cases contain PS and can be recycled into vests, foam packaging, insulation, and flower pots.
Lastly, Polyvinyl Chloride (PVC), a resin with stable physical and electrical properties, chemical resistance, weather ability, and flow characteristics as well as high impact strength, clarity, processing performance, resistance to grease, oil, and chemicals and is the world’s widely used synthetic plastic. It has two forms, rigid and flexible. The rigid form helps manufacture blister packs and clamshells while the flexible forms create bags for bedding and medical, shrink, deli, and meat wraps tamper-resistant. Its products can later be recycled for piping, kayaks, packaging, traffic cones, post boxes, and speed bumps.
These resins provide the durability factor to plastics that protects keepsakes, food, electronics, and shipping products. They prevent and protect damage or contamination caused during transport, by moisture, microorganisms, insects, and light. Spillage while transporting to distances and also during usage of products is avoided thereby preventing waste. Household goods and gadgets, books, toothbrushes, sports equipment, etc. are shielded from scratches and dents that arise during transport.
Plastics promote resistance to corrosion and bio-inertness making plastic resource efficient while saving 75.8 million metric tons of carbon dioxide. It also provides preservation to products for an extended shelf life thus preventing waste.
17% percent of packaging involves plastic that makes the product lightweight, unlike its substitutes that are 4-5 times heavier as they require more material output for packaging. Lightweight but strong, it protects the product without adding extra weight thus save manufacturing, transportation, and shipping costs. Being lightweight leads to superior sustainability, lowers energy consumption, material resource efficiency, and greenhouse gas emissions.
The durability and lightweight qualities make packaging possible by using fewer resources, occupying less space in transport that then requires fewer modes of transportation due to lighter loads hence lower emissions. Products are delivered in a perfect condition and consequently increases trade.
The versatility of plastic helps build moulds into limitless shapes like bags, pouches, films, flow wraps, sleeves, shells, trays, pots, bottles, drums, etc. The mould fits of packaging are customized to the shape of products into a box, spherical, cylindrical, and many other shapes. It allows the product to provide a tight, simple, open form or hanger seals to hold hot foods, cold liquids, acids, or bases. From button cell batteries to bicycle pallets, versatility creates varied transformation in blown, injected, thermomoulded, decorative effects and colors, safety mechanisms, or shut seals like childproof locks on medication.
“Education is required to know what is recyclable and what is not.”- Clare Goldsberry.
The myth that paper is an all-time replacement for plastic depicts ignorance of the science that lead to poor decision-making. Basic paper cups are lined with polyethylene, plastic, to prevent dissolving. Plastics have multipurpose usages in common households as garbage bags, to carry or transport food and most frequently for packaging. The usage of plastic was always existent however the real problem was not plastic but people littering it rather than recycling, resulting in disposal complications.
An article in Plant Money determined that plastic bans may have reduced non-biodegradable litter but on the contrary, paper bags are worse because they require trees to be cut or a high percentage of recycled paper to be processed using lots of water and toxic chemicals and fuels for the production machinery.
According to Igor Catic, Professor Emeritus of Plastics Engineering at the University of Zagreb, Croatia, “Several ecological problems are cropping up with increased use of paper bags and must be used 43 times to be ecologically productive. Conversely, cotton bags have an even worse impact than plastics. They require fuel to grow and machines that use diesel or gasoline to work.” The Plant Money article states that cotton bags must be used 20,000 times.
Biodegradable, Polyhydroxyalkanoate (PHA), sustainable products i.e. eco-friendly alternatives to plastics and other petrochemical plastics are some of the many new components that will be used to upgrade plastics usage soon. PHA products saw developments and productions from 2018 through 2019.
According to Dr. Jenna Jambeck and her team of researchers, April 2018, on the biodegradability aspect of PHA, compared PHA plastics with petrochemical plastics and found, “PHA is biodegradable in an anaerobic environment and its landfill degradation would take up to 40-60 days. While, petrochemical plastics degenerate in aerobic, sea or ocean, environments in 6 months.”
This research proved PHA to be a promising eco-friendly alternative to avoid the petrochemical waste that sustained harm to the environment. The future goal of many packaging industries is to create snack bags that are home compostable and to add PHA in straws, cutlery and cosmetics packaging.
The plastics industries use bio-based and compostable materials to promote sustainability. The flexible packaging stimulated industry collaborations of more than two supplier partners on a global scale. Compostable snack bags by PepsiCo and Danimer Scientific use traditional bio-based flexible packaging. Their packaging has right balanced sustainability, high performance, cost-effective, material that has a feeling comparable in noise and quality made of traditional film resins.
Current plastics packaging have multisensory elements that mimics leathery or soft-feel materials thus making it look attractive. They also possess a high-performance structure in reusability, brand benefits and quality that gain brand-loyal customers. The printing and graphics also add to the authenticity and overall quality.
New plastics packaging have extended shelf life properties as well as recyclability along with storage capabilities and ovenable films for food items and microwaveable convenience as well. Thus, along with the capacity to store its content efficiently, the consumer can heat the food package in an oven or a microwave and can store it back into the fridge without the need for transferring it into a container.
In conclusion, plastic bag packaging is one that enables plastics industries to get their products across the consumer without letting the consumer have the benefit of doubt in regards to the environment and the sold product. Along with aiding the environment, it provides for a circular economy and grants many secure jobs and to minimize losses.