At Dotmar Engineering Plastics, sustainability and manufacturing efficiency go hand in hand. Through a combination of in-house recycling systems and carefully managed material reuse processes, Dotmar Injection Moulding continues to reduce production waste while maintaining the high-quality standards expected across industrial plastic components.
One of the key initiatives within the facility is the reuse of post-industrial regrind — plastic material reclaimed directly from the manufacturing process. Rather than discarding usable polymers, production waste is recovered, reprocessed, and reintroduced back into selected moulding applications where specifications allow.
Recycling a Wide Range of Engineering Polymers
Dotmar Injection Moulding primarily recycles High-density polyethylene (HDPE), Polypropylene (PP), and Acrylonitrile butadiene styrene (ABS), although the facility has the capability to recycle many other thermoplastics depending on the application and product requirements.
The amount of recycled material that can be reused is influenced by both the availability of suitable regrind and the performance specifications required for the finished component.
Two In-House Recycling Streams
Dotmar utilises two primary in-house recycling methods within its injection moulding operations.
The first occurs directly at the moulding machine through the use of small granulators positioned beside production equipment. These units are typically used to process sprues, runners, and smaller moulding waste items immediately after production, allowing the material to be quickly reintroduced into the manufacturing process
The second recycling stream involves a larger central granulator designed for processing bulkier rejected mouldings, returned parts, and larger production scrap. Operating for an average of approximately three hours per day, the granulator reduces plastic waste into reusable flake material.
This flake is then bagged and reused in future moulding runs. During production, the recycled flake enters the process through the hopper, moves into the barrel, and blends with molten virgin polymer prior to the injection moulding phase.
Working with Specialist Recycled Material Suppliers
In addition to internal recycling capabilities, Dotmar also partners with external suppliers specialising in recycled polymer processing. These suppliers reprocess larger volumes of recycled plastics into blended or fully recycled raw materials, which are then purchased and used alongside virgin resins where appropriate.
This approach provides greater flexibility in sourcing recycled content while helping maintain consistency in material performance.
Balancing Sustainability with Product Performance
While recycled materials offer significant environmental and commercial advantages, successful implementation within injection moulding requires careful process control.
One important consideration is recycled material percentage. In many applications, incorporating up to 20% recycled content can be achieved without negatively impacting product performance, although this is highly dependent on part design, application requirements, and engineering specifications.
Material consistency also plays a critical role. Recycled polymers can exhibit variations in melt flow index (MFI), tensile strength, and processing characteristics compared to virgin materials. Additionally, contamination or repeated thermal cycling during the material’s lifecycle can affect long-term mechanical performance if not properly managed.
For this reason, Dotmar carefully evaluates where recycled materials can be successfully integrated without compromising quality or reliability.
Designing for Sustainable Manufacturing
Successfully using recycled polymers often begins during the product design phase. By understanding the mechanical requirements and performance expectations early in development, products can be designed to better accommodate recycled content.
Working closely with trusted material suppliers also enables tailored resin blends to be developed for specific applications, helping balance sustainability goals with technical performance requirements.
As industries continue to focus on reducing waste and improving material efficiency, Dotmar Injection Moulding remains committed to practical, responsible recycling solutions that support both manufacturing performance and environmental outcomes.
