In 2021, China built its first plastic road using 6,000 milk bottles; the result turned hard-to-recycle plastic waste into useful paving material

In 2021, thousands of used milk bottles in Shanghai found a second life. More than 6,000 bottles, along with other plastic waste, were used in a road project at East China University of Science and Technology, turning material that recyclers often struggled to accept into part of a polymer-modified asphalt surface. The project, unveiled on Earth Day, was developed by Dow and dairy brand Shiny Meadow to tackle the problem of hard-to-recycle plastic. Instead of ending up as waste, the bottles were processed for road paving, offering an unusual route for plastic that had little value in conventional recycling.Why milk bottles were hard to recycleAccording to the official Dow press release, milk bottles might be suitable for recycling. The bottles were technically recyclable, but recyclers are often unwilling to accept them because leftover milk residue caused a high rate of contamination. That meant a material that could be recycled could still end up being treated as waste rather than as a useful resource.Shiny Meadow also acknowledged the difficulty of dealing with bottles at the end of their useful life. Lin Rong, the brand’s director, said the company had already been using recyclable packaging materials but that there was still a gap when it came to bottles that recycling companies regarded as low-value plastic. “We are pleased to have found a meaningful use for our empty bottles,” Lin said, describing the road project as a way of giving the packaging a more circular journey.Dow turned plastic waste into road materialDow's solution collects the hard-to-recycle plastic and turns it into post-consumer recycled plastic for polymer-modified asphalt. The recycled material was then incorporated into the road paving process, turning thousands of unwanted bottles into part of the infrastructure at ECUST's Xuhui Campus. In total, more than 6,000 used milk bottles and other plastic waste went into the project.The project was also presented as an example of how materials science could create new uses for plastic that traditional recycling systems struggled to handle. Bambang Candra, Dow’s Asia Pacific commercial vice president for Packaging & Speciality Plastics, said, “Using our materials science expertise, we help bring a new purpose to waste bottles.” He added that the company hoped the project would encourage other brand owners to find ways of reducing plastic waste.How the plastic road could cut emissionsThe project was intended to do more than simply dispose of unwanted plastic in a different form. Dow said keeping the waste out of the environment, reducing the amount of bitumen required and potentially extending the service life of roads could also reduce greenhouse-gas emissions and energy consumption. The company therefore presented the road as an example of turning a waste problem into an infrastructure application.For Shiny Meadow, the project fitted into a broader idea of circularity. Lin Rong said the company wanted its plastic packaging to have “a circular journey” rather than follow a traditional take-make-use path. The road offered one possible destination for plastic bottles that had little value to conventional recyclers, giving the discarded packaging a practical use after its original purpose had ended.Dow’s recycled plastic road projects across AsiaThe Shanghai project was part of Dow’s wider work on using recycled plastic in roads across Asia. The company said it had begun improving roads with recycled plastic in Depok City, Indonesia, in 2017. It later worked with partners in India on roads in Pune and Bangalore and had begun a collaboration with Siam Cement Group in Thailand.ECUST viewed the Shanghai road as a practical demonstration of how unconventional approaches could be used to tackle plastic waste. Professor Li Tao, the university’s vice president, said the institution hoped the collaboration would inspire students to explore unusual sustainability solutions and apply creative ideas on a larger scale.Catch the latest World News and Live updates. Download the TOI app.