For a company founded just five
years ago, Polyphalt has an ambitious goal. As Bruce Harbinson, Polyphalt's president said
"we want to be the global leader in developing and commercializing polymer modified
asphalt. Getting there sometimes seems like a long road but we now have an established
portfolio of technologies, developed incidentally right here in Ontario; we have an
established base of licensees; and, with the introduction of performance grade
we are getting inquiries from all over the world."
For Polyphalt, that road started on College
Street at the University of Toronto's Department of Chemical Engineering. It was 1989 and
Zhi Zhong Liang, a former lecturer at Beijing University of Chemical
Technology, was working as a research
associate for Professor Laverne Williams studying phase behavior in polymeric blends.
Asphalt was not one of Zhi Zhong's interests but when he heard that Ray Woodhams was
giving a presentation on the use of polymers to modify asphalt, the idea intrigued him.
Going to that presentation, recalls Zhi Zhong, was one of
those lucky coincidences that almost seems predestined. Ray Woodhams, now retired, was a
senior professor in the Department and with a string of patents to his name, one of the
University's most prolific inventors. He and his students had made significant progress in
an asphalt research project but the problem of maintaining a stable dispersion of
polyethylene in asphalt stubbornly resisted solution. Zhi Zhong recognized that his
previous work in reactive polymer processing had implications for Professor Woodhams'
research. Professor Woodhams recognized a fresh approach to a seemingly intractable
problem. Four months later, they had a proprietary system of steric stabilization that
"reacted" the polyethylene with the asphalt to maintain a stable dispersion of
While the technology held enormous potential, the
University did not have the resources to scaleup the process. It did however interest John
Harbinson, at the time a successful businessman in Aurora, Ontario. In May 1992, John
licensed the rights to the U of T technology and set up Polyphalt as the company to bring
the technology to market.
Five years later, Polyphalt has a well established reputation for innovative technology
although, as Bruce Harbinson notes a trifle ruefully, they still get calls from people
wanting a load of asphalt. "We are probably the best-known company in the asphalt
business that doesn't sell asphalt...
at least not yet" said Bruce.
What Polyphalt does produce is technology. From
the groundbreaking stabilization work in the early '90s, the company has expanded what
Bruce calls its "portfolio of processes" to include elastomers, plastomers and
crumb rubber both individually and in combination. Designated by Polyphalt as SPx (for plastics), EPx (for rubber and plastics combination) and DVx (for rubber), the processes are equally
adaptable for use with recycled resins, opening up new supply options and, in many cases,
"When you consider what we deliver, the portfolio is
essential," said Bruce. "Our job is to make better asphalts not to promote one
particular system. No one modifier is appropriate for all situations. Through a very
strong program of product development we have been able to engineer asphalts through
modification that meet all performance requirements regardless of asphalt type. That gives
our licensees the scope to provide the right asphalt for the job."
Polyphalt now licenses its technology to producers in the US,
Canada and Australia who have used the technology in dozens of high profile projects.
Yellowstone National Park's Sylvan Pass (9,000 feet above sea level in one of the coldest
regions of the US), the main runway at the Spokane International Airport in Washington,
the California Speedway and Sydney's M-4 Motorway have all been paved with Polyphalt's
|With 3,000 pound cars racing at over 200 miles per hour on high banked
oval tracks, pavements need to be tough enough to resist the stress and yet smooth enough
to provide ideal racing conditions.When the pavement at the turns on the St. Louis's
Gateway International Raceway failed last year contributing to 13 crashes and crumpling a
million dollars worth of racing metal, designers realized they needed a tougher pavement.
The new California Speedway was paved with engineering asphalt produced by
Huntway using Polyphalt technology
They selected Polyphalt's EPx
system which co-reacts styrene butadiene styrene, low density polyethylene-ethylene and
asphalt into an extremely tough and stable product. Polymer Asphalt Products, a Polyphalt
licensee, produced a PG 82-22 modified asphalt which in spite of an initial softening
point in excess of 104C, was reported to have paved like an unmodified asphalt. After
several months of use, the new pavement continues to provide the excellent surface race
car drivers demand.
The first of Polyphalt's North American licensees was Huntway
Refining in California, the largest supplier of polymer modified asphalts on the US west
coast. Bob Rivers is Huntway's Manager of Product Development and worked with Polyphalt
from the start. "We met Polyphalt at an industry conference when they were just
starting the business," recalls Bob. "What spurred our interest was their
ability to stabilize polyethylene in asphalt which was a technology nobody else had.
Interested in capturing an increased share of the developing market for modified asphalt,
Bob and Bill Darnell (Vice President and General Manager at Huntway) pursued the Polyphalt
connection becoming a licensee in 1994. Huntway was not a stranger to polymer modified
asphalts. They had a Sieffer high shear modification system in place to produce asphalts
modified with styrene butadiene styrene. The immediate advantage of Polyphalt's process,
Bob Rivers, was that they could replace SBS with lower priced polyethylene whether virgin
or recycled. By 1995, the first production test was ready modified asphalt for Interstate
5 near Redding, California, the most
heavily traveled highway in the state. Timing of the license agreement couldn't have been
better. While demand for polymer modified asphalt was growing. In many cases, however,
California Oregon and Nevada specifications were different. Huntway had to make a number
of small production runs with various modifiers to produce the type of PMA the contractors
required. Polyphalt's technology, said Rivers, had the flexibility that allowed Huntway to
combine similar specifications into a single sales tank. The more forgiving nature of the
Polyphalt process also gave Huntway access to previously unmodifiable asphalt bases,
contributing to a more flexible approach to meeting specifications. "That allowed
larger production batches and obviously, better economies of scale."
In 1996, Huntway supplied a PG 76-22 grade of
asphalt for the reconstruction of the California Speedway. It was a special application
requiring a high degree of modification and the sort of project that doesn't come along
every day. More typical was the January 1997 project, a very thin overlay on Highway 80
near San Francisco for which Huntway supplied polymer modified. Carried out in extremely
cold conditions (for California) at night to avoid traffic disruptions, the project was,
for Rivers, typical of the performance they have come to expect. "The mix didn't
adhere the trucks, emissions at the hot plant were low, we achieved a very consistent
compaction and the final product had that beautiful sheen of an opengraded mix,"
Rivers reports. In 1997, Huntway supplied over 40,000 tons of polymer modified asphalt
more, the company claims, than any other producer in the state.
DRIVING TO THE FUTURE
At Polyphalt's head office in Toronto, the company maintains one of the largest and
best equipped asphalt research laboratories in the country. Zhi Zhong Liang is Polyphalt's
vice-president of technology and heads up the effort to develop new products.
"We're continually refining our existing processes
particularly as we work with our licensees. The experience they gain in the field is
absolutely invaluable," said Zhi Zhong. Basic product development is not ignored,
however. "There are two areas where we are concentrating right now," Zhi Zhong
said. "We see some significant promise in our crumb rubber work. Crumb rubber comes
from used tires which means it is relatively plentiful and economic but it is limited as a
modifier because the rubber has been vulcanized. In other words, it is no longer reactive.
Our work with devulcanization means that the rubber can become an active modifier again.
You get all the benefits of rubber modification and establish an economic value to what is
a huge waste product."
The other area of research that Polyphalt is
actively developing was part of the impetus for Bruce Harbinson and Zhi Zhong Liang's trip
to China - a concentrated polymer modified asphalt that will significantly extend the
distribution channel between the PMA manufacturing facility and the hot mix plant.
"The asphalt will be modified and concentrated so that it can transported
conveniently over long distances without degradation," said Zhi Zhong. "That has
three advantages. First, asphalt plants can produce product in non-peak times which has
obvious economic advantages. Second, we can ship to remote sites without any product
degradation which means that potentially producers could even ship internationally.
Finally, no specialized equipment is required at the point of use. The product can be
easily diluted or even introduced directly into the pug mill" On the commercial side,
the biggest boost to Polyphalt's technology has come from the Strategic Highway Research
Project and the move to performance specifications. "When contracts were awarded to
the lowest bidder, PMAs were at a significant disadvantage because they cost more,"
said Bruce Harbinson. "That's changing rapidly. Agencies are now looking at
life-cycle costing of pavement. For effective life-cycle costs you need performance and in
many cases you simply cannot meet the performance requirements of these specifications
without some degree of modification. With market acceptance of SHRP performance grade
specifications expanding dramatically over the last year, PMA demand has increased. So too
have the number of inquiries from asphalt producers." Considering that Polyphalt has
parlayed a single patent into a broad technological base in just five years, the level of
interest in their processes demonstrates that Ontario's asphalt technology can compete
with the best in the world.