Invented back in the late 1800s, plastic injection moulding was developed to meet the demands of mass production, however, there was little to no consideration of the environmental impact. Today, sustainability is an important factor in the industry, with new materials, technology, and practices being developed to reduce the environmental footprint of this process. Let's take a look into sustainability and recycling in plastic injection moulding.
Sustainability in Plastic Injection Moulding
Sustainable materials
During the Design for Manufacture (DFM) stage in plastic injection moulding, the potential use of sustainable materials, such as recycled plastics or biopolymers, is actively evaluated as an alternative to virgin materials.
By selecting sustainable plastics derived from post-consumer or post-industrial waste into the injection moulding process, manufacturers can lower their carbon footprint and contribute to a greener economy. Recycled materials reduce the environmental impact of plastic manufacturing, and address concerns related to excessive waste generation.
Energy efficiency
Energy efficiency is a key aspect of sustainability in plastic injection moulding, and modern advancements in machinery are playing a huge role. Modern electric injection moulding machines are more energy efficient than older models, so they use less power and have less carbon impact.
Process optimisation
By streamlining operations and minimising waste in injection moulding, manufacturers can reduce their environmental impact while improving profitability. Processes such as cycle time (the time it takes to complete one full cycle of the injection moulding process) can be reduced whilst being more efficient of time.
Another way processes can be optimised is through the use of precision moulding techniques. These techniques such as micro-moulding and thin-wall moulding enable the production of smaller, lighter parts reducing in lower material costs and reducing waste.
Waste conversion
In fully optimised injection moulding processes, the goal is to minimise waste by only using the precise amount of polymer needed to fill the mould. This ensures that excess material is not consumed.
In cases where waste is unavoidable, advanced techniques can be employed such as converting the waste back into usable polymer for future production runs. This not only preserves raw materials, but also significantly reduces the environmental footprint of the manufacturing process.
Recycling in Plastic Injection Moulding
Recycling processes
Recycling is highly important in plastic injection moulding as it offers a way to reduce the environmental impact of plastic waste. Recycling in injection moulding typically includes collecting waste material and reprocessing it into new products.
It’s also important to consider plastic polymers that can be recycled when you no longer need the product being made. Polyethylene Terephthalate (PET) and High-Density Polyethylene are both widely recyclable plastics that are commonly used in the plastic injection moulding process.
Use of recycled materials
Recycled materials are becoming increasingly common in plastic injection moulding as companies are trying to meet sustainable goals and the demand for eco-friendly products from consumers. To reduce the demand for virgin polymers, manufacturers can use recycled plastics by re-grinding waste plastic and blending it with virgin material. This process maintains the desired material characteristics while incorporating recycled content.
Incorporating recycled plastics in plastic injection moulding not only helps reduce waste, but also conserves natural resources by reducing the need for virgin plastic production where possible.
The Future of Sustainability in Injection Moulding
The future of sustainability in plastic injection moulding is being driven by innovative materials, technology, and eco-friendly practices. Bioplastics derived from renewable resources like corn starch and sugarcane are becoming the go-to environmentally friendly alternatives to traditional practices. Composite materials are also enhancing the strength and durability of moulded components for certain applications.
The plastic injection moulding industry is also focusing on recyclability and reuse of plastic components to minimise waste. Despite challenges that plastic injection moulding faces, there is ongoing research, collaboration, and advancements in bioplastics and mould tool design that are crucial to helping the industry remain a sustainable and responsible choice.
