Plastic waste used as plywood binder

The country’s waste management program stands to benefit considerably from a new technology developed by a Los Baños, Laguna-based government research institute utilizing plastic waste as binder for plywood and particle boards.

The technology was developed by researchers of the Department of Science and Technology-Forest Products Research and Development Institute (DOST-FPRDI).

Behind the breakthrough are researchers Hilario Dolores, Mildred Fidel, Vicente Mallari Jr., Alberto Nicolas, Nathaniel Ramos and Antonio Centeno.

The study was funded by the Philippine Council for Industry and Energy Research and Development (PCIERD), a sister-agency of FPRDI.

The new technology boosts efforts to manage waste, specifically plastic which is non-biodegradable.

Metro Manila alone, which is populated by about 10.5 million people, generates about 6,500 metric tons of garbage daily, 17 percent of which (about 1,020 metric tons) consist of plastic.

A giant food conglomerate alone churns out five to six tons per month of plastic aluminum packaging laminates (PAPLs) and oriented polypropylene laminates (OPLs) for the packaging materials of its food products and drinks and for candy wrappers.

In the FPRDI research, mixtures of low, medium and high-density polyethylene (LMHPE) plastic waste, OPLs and waste PAPLs were used as binder in the production of laboratory and commercial-sized three-ply plywood and one-layer particle boards.

Fifty-four laboratory lauan plywood panels measuring 30 x 30 centimeters were produced using three pressing times (five, 10 and 15 minutes), two pressing temperatures (130 and 150 degrees Celsius), and three plastic spreads (100, 120 and 140 grams per square meter) as variables.

The plywood samples produced were subjected to delamination and cyclic boil tests following PNS 196:2000 plywood standards.

Results showed that all laboratory plywood samples bonded with LMHPE, PAPL and OPL passed the delamination test for type 2 or interior plywood.

Commercial-sized plywood measuring 122 x 244 cm were produced during mill testing using recycled waste plastic film with 25 percent virgin polyethylene plastic and 75 percent PE plastic waste.

The mill testing was done in five plywood mills.

"Because plastic-bonded particle boards absorb moisture and do so more slowly than solid wood, they have better fungal resistance and dimensional stability when exposed to moisture," the FPRDI researchers said.