Researchers in 2020 developed a new structural material by combining sand with a small amount of polyethylene (PE) and compacting the mixture under high pressure. The study found that the resulting material could achieve flexural strength comparable to, and at certain formulations greater than, typical steel-reinforced concrete in laboratory tests.
The material uses polyethylene as a binder instead of Portland cement. Researchers mixed sand with PE particles and heated the mixture to around 200°C before applying pressure. At about 10% polyethylene by weight, the composite reached a flexural strength of approximately 23 MPa.
The research also showed that the amount of plastic and the compaction pressure affected performance. The researchers identified 7–10% polyethylene and 70–100 MPa of compaction pressure as a useful range for producing the material. Increasing the polyethylene content beyond 10% provided smaller additional gains in strength.
The approach could potentially address two environmental challenges at once: the difficulty of recycling certain plastic waste and the carbon emissions associated with Portland cement production. However, the findings were based on laboratory testing, so further research and engineering validation would be needed before considering widespread structural construction applications.
