Engineers develop process to recycle unused paint by blending it into common plastics

Mar 20, 2007

Engineers at Rutgers, The State University of New Jersey, have developed a process to recycle waste latex paint – the largest component of household hazardous waste – by blending it with common plastics. In laboratory samples, these paint-blended plastics were as good as, and in some cases, superior to the same plastics made without paint.

To advance this promising technology toward commercialization, Rutgers signed a special licensing agreement with Re-Manufacturing Technologies, Inc., a new spinoff of the National Council on Paint Disposition, Inc. That group was formed by a long-time paint dealer and businessman in 2002 to develop a viable approach for reducing the disposal costs and environmental impact of waste paint products.

“Many municipalities forbid discarding paint in the trash because it’s an environmental nuisance – it spills from cans that garbage trucks crush, defacing streets and contaminating refuse-handling equipment,” said Tom Nosker, professor of Materials Science and Engineering at Rutgers and principal investigator at a university center for advanced polymer materials. “They’ve responded by accepting unwanted paint during household hazardous waste recycling days, but then they’re left holding the bag, having to contract for proper waste management at almost $9 per gallon. An effective recycling solution could cut that cost, and possibly even become a money maker.”

Nosker noted that unwanted paint has become the largest component of household hazardous waste – some 68 million gallons annually. And this doesn’t even account for large quantities of paint that commercial painters and retailers dispose because of incorrect tints and inventory miscalculations.

As part of the Rutgers center’s ongoing work in plastic recycling, Nosker and postdoctoral research fellow Jennifer Lynch tested the feasibility of blending latex paint solids with two inexpensive and widely available plastics. One is high-density polyethylene (HDPE), commonly used to make milk and laundry detergent bottles; the other is polymethyl methacrylate (PMMA), used in Plexiglas and similar acrylics to make plastic windows and lenses. The paint solids, which remain after the paint’s water-based solvent evaporates, are essentially acrylic polymers and colorants.

The engineers found that paint blended with polyethylene exhibited similar characteristics and performance as pure polyethylene, with the advantage of consuming unwanted paint and reducing the amount of HDPE feedstock. The paint and polymethyl methacrylate blends sacrificed transparency, but made the otherwise-brittle plastic more flexible and tough while maintaining stiffness and strength. As a result, paint-blended PMMA might be able to compete with more expensive plastics that combine strength and flexibility, such as for laptop computer housings that need to withstand bumps and falls.

Nosker also noted that plastics made with recycled paints could be used to make paint containers, eliminating metal cans and essentially bringing the paint product’s life cycle full-circle. It’s also possible that unused paint and the plastic paint container that holds it could be recycled together.

The engineers plan to explore recycling oil-based paints, used far less today than latex paint but representing a greater environmental threat, and look into other petroleum-based materials that unwanted paints could effectively extend.

Source: Rutgers, the State University of New Jersey

Explore further: Britain to trial driverless cars from 2015

add to favorites email to friend print save as pdf

Related Stories

Sustainable algae cultivation making headway

Jun 11, 2014

Four years after the first optimistic calculations, the experimental cultivation of algae appears to be meeting expectations. Production costs have been more than halved, while the profit made on some crop components already ...

New class of industrial polymers discovered

May 15, 2014

(Phys.org) —Scientists from IBM Research have successfully discovered a new class of polymer materials that can potentially transform manufacturing and fabrication in the fields of transportation, aerospace, ...

Turning waste into wealth

Mar 21, 2014

Waste is a valuable resource that could earn the UK tens of billions of pounds, according to a new report by the House of Lords Science and Technology Committee.

Painting in virtual reality, no trial-and-error

Feb 19, 2014

Almost any product made of plastic, metal or wood is painted or coated. But colour doesn't come cheap. The biggest polluter in a factory is the painting and surface treatment processes. By painting in virtual ...

Recommended for you

Printing the metals of the future

23 hours ago

3-D printers can create all kinds of things, from eyeglasses to implantable medical devices, straight from a computer model and without the need for molds. But for making spacecraft, engineers sometimes need ...

3D printing helps designers build a better brick

Jul 29, 2014

Using 3-D printing and advanced geometry, a team at Cornell has developed a new kind of building material – interlocking ceramic bricks that are lightweight, need no mortar and make efficient use of materials.

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

xiwen
not rated yet Nov 22, 2007
Hi everybody,

for more information about pmma and pc recycling check www.heathland.nl.

This is an informative website on the process of PMMA and PC recycling. Recommended for people with an interest in recycling or people working in the industrial sector.

Best regards,

Xi Wen