The second installment of Polyco’s Back to Black webinar series, A Producer’s Perspective of PGTR for a Sustainable Future, continued the conversation on the evolution of tire rubber asphalt, bringing together leading experts to explore innovations in sustainable pavement solutions. Hosted by Bob Rivers, this session revisited key takeaways from CalAPA’s 2021 discussion on recycling tire rubber for asphalt and examined new advancements in rubber-modified binder technologies.
Peter Sebaaly, Ph.D., Director of the Western Regional Superpave Center at the University of Nevada, Reno, spoke first on the performance of tire rubber modified mixtures, sharing groundbreaking research on pavement performance. His study demonstrated that asphalt concrete (AC) pavements incorporating tire rubber significantly outperformed unmodified AC pavements. His conclusion emphasized that utilizing tire rubber can extend pavement life and reduce tire waste, making it a win-win for infrastructure and the environment.
Then, Bob McGennis, who brings over four decades of experience in asphalt technology and currently serves as the Asphalt Technical Manager for HF Sinclair Corporation, delivered a presentation on the basics of performance graded terminal blended (PGTR) asphalt. He covered the fundamentals of crumb rubber asphalt and explained how specifications drive the manufacturing and engineering properties of PGTR systems. He also discussed the essential features of PGTR systems and their role in improving asphalt performance.
Drawing from his experience at Pacific Emulsions, Lance Allan discussed the benefits of modified slurry seals, highlighting how tire rubber modified slurry seals improve durability and visual appeal. He shared how projects like the City of Oceanside’s pavement treatments have successfully utilized this technology for almost two decades.
Finally, Skip Brown, a respected pavement consultant with over 60 years in the industry, shared his firsthand experience with Polyco’s Terminal Blend PG 64-16 TR 15% supplied by Pacific NorthWest Oil Company. His insights reinforced the importance of innovation in binder technology for achieving long-lasting, high-performance pavements.
The webinar concluded with an engaging Q&A session, where panelists discussed the practical applications of rubber-modified asphalt. They confirmed that tire rubber modified slurry seal can be applied using conventional slurry seal equipment, making it accessible for widespread use. The discussion also touched on legislative efforts to encourage the use of recycled rubber and reclaimed asphalt pavement (RAP), as well as the growing adoption of rubber-modified binders in western states. Experts highlighted the proven performance benefits of terminally blended asphalt with tire rubber, reinforcing its importance in advancing sustainable pavement solutions.
Looking ahead, the Back to Black series will continue to explore the latest advancements in asphalt technology, bringing together industry leaders to discuss emerging trends, best practices, and the future of sustainable infrastructure. Stay tuned for details on our next session.
If you missed this session, or want to rewatch the conversation, access the full recording to gain valuable insights.
The first installment of our Back to Black webinar series, Not Lost in Translation, brought together two distinguished experts from opposite sides of the Atlantic to discuss the latest advancements in rubberized asphalt performance.
Henrique Borges Miranda, Ph.D., a pavement engineer and assistant professor at Instituto Superior de Engenharia de Lisboa, shared insights from his groundbreaking work in Portugal, including research on incorporating crumb rubber tire waste into asphalt mixtures. Attendees were treated to an engaging presentation featuring a comparative analysis of dry and wet processing methods, as well as real-world case studies and a fascinating video demonstration of elastic recovery testing from Brisa laboratories in Portugal.
Joining Henrique was Robert Lee, P.E., Regional QC Director for Texas Materials. With nearly four decades of experience, Robert offered a U.S. perspective on sustainability in the asphalt industry. In a dynamic discussion with host Al Palmer, he highlighted innovative projects throughout Texas utilizing specialty mixes and shared how his team leverages Polyco’s SigmaBond to enhance asphalt performance. Missed the webinar? You can still explore these exciting discussions and gain valuable international perspectives. Watch the recording now and join us on the journey to redefine asphalt performance and sustainability.
At Polyco, we’re always pushing the boundaries of innovation in asphalt modification. One of our biggest breakthroughs is SigmaBond—a high-performance asphalt binder that includes recycled tire rubber that is liquefied through our unique chemical process (Rapid Digestion Process™). Unlike traditional methods that simply blend crumb rubber with asphalt, RDP harnesses the power of pyrolysis to chemically transform tire rubber, enhancing asphalt performance and sustainability.
The Science Behind SigmaBond: More Than Just Blending
When our chemists first began developing SigmaBond with RDP, the process started with a simple lab setup—heating asphalt to extreme temperatures and adding tire rubber to see what would happen. What we discovered was remarkable: at around 600°F, the rubber particles were no longer visible when passed through a sieve. At this temperature, the tire rubber breaks down into its base components, allowing it to homogeneously blend with asphalt mixtures.
This reaction, known as pyrolysis, is the key differentiator between SigmaBond and conventional rubberized asphalt. Instead of mixing rubber particles into asphalt (the “wet” or “dry” methods used by competitors), we use heat to break rubber’s long polymer chains into smaller molecules. This results in a stable, homogeneous blend of asphalt—a combination that enhances durability, elasticity, and overall pavement performance.
Why Pyrolysis Matters
Most rubberized asphalt technologies do not chemically alter the tire rubber; they merely suspend rubber particles in the asphalt, which can lead to separation, inconsistent performance, and processing challenges. With SigmaBond, the controlled pyrolysis process ensures a permanent chemical transformation, producing a smoother, longer-lasting asphalt blend.
Since tire rubber consists of several complex bonds—carbon-carbon, carbon-sulfur, and sulfur-sulfur—each requires different levels of energy to break. By carefully managing temperature and reaction time, RDP optimizes these chemical changes, ensuring the right balance of rubber integration without unwanted byproducts. This results in an asphalt modifier that retains the benefits of rubber without the downsides of high viscosity or poor mixability.
Performance & Sustainability Benefits
SigmaBond offers a range of advantages for pavement applications:
- Superior Durability: The enhanced elasticity and stability of SigmaBond-modified asphalt reduce cracking and extend pavement lifespan.
- Smoother, Darker Surfaces: The high carbon black content gives roads a deep black finish, which some customers have noted as a visual advantage.
- High Rubber Content: SigmaBond can incorporate up to 50% tire rubber by weight, making it one of the most sustainable asphalt solutions available.
- Better Workability: Despite its high rubber content, our proprietary process ensures that SigmaBond remains easy to transport, mix, and apply.
Setting a New Industry Standard
At Polyco, we’re not just modifying asphalt—we’re redefining how recycled materials can be used to build stronger, more sustainable roads. By introducing pyrolysis into the equation, SigmaBond represents a fundamental shift in asphalt technology, offering unmatched performance and environmental benefits.
As the industry moves toward more sustainable infrastructure solutions, SigmaBond stands at the forefront, proving that innovation and environmental responsibility can go hand in hand.
For many years, post-manufactured and post-consumer asphalt shingle waste was successfully recycled into asphalt paving, providing both a sustainable and cost-effective alternative to landfill disposal. At one time, asphalt paving companies even paid for post-manufacturing waste due to the value of the unaged asphalt.
As paving regulations evolved to become more sustainable, the industry prioritized the use of Recycled Asphalt Pavement (RAP), a proven and essential component in modern asphalt mix design. While RAP plays a critical role in sustainable paving, this shift has significantly reduced demand for Recycled Asphalt Shingles (RAS). The post-manufactured waste may still have options in paving due to the value of the unaged asphalt, but the roof tear-off shingles that are a large majority of the RAS will be used less in paving. At the same time, landfill restrictions on asphalt shingles continue to expand, creating additional pressure to find viable recycling solutions.
To ensure long-term sustainability, the industry must explore new ways to integrate RAS into both paving and roofing applications—maximizing its value across multiple sectors.
The Need for Industry Collaboration
Prior to joining Polyco, I worked in the asphalt shingle market for Elk and GAF for almost 23 years. This experience taught me that it’s crucial for manufacturers to collaborate in updating industry codes to expand opportunities for shingle recycling. If immediate and deliberate changes are not made, the ability to use asphalt shingles in the future could become problematic due to end-of-life limitations.
The Importance of Updating Industry Codes
It is clear that significant and rapid gains must be made in the use of RAS in the production of new asphalt shingles. However, this opportunity has its challenges.
There are two codes that provide criteria for evaluating asphalt shingle products. ASTM D3462 has been in place for many years and “is somewhat prescriptive and contains multiple weight measure requirements, which tends to limit future asphalt shingle innovation and product development.” In contrast, AC438, published in March 2012, “is largely testing- and performance-based with minimal prescriptive, weight and measure requirements.”
Despite the apparent advantage of adhering to AC438, the industry continues to give greater credence and weight to the ASTM D3462 code. To advance the asphalt shingle industry, we must phase out ASTM D3462, expand support for AC 438, and develop additional codes that allow for even more flexibility and creativity in asphalt shingle design—paving the way for increased use of recycled materials.
Processing Challenges for Recycled Asphalt Shingles
Depending on the method used to process RAS, separating and concentrating the shingle raw material components can lead to mass and/or energy balance challenges. Mechanical methods can remove most of the large headlap and butt (colored) granules, which can then be reused as headlap granules in new shingles. This is the easiest part of the process, with minimal impact on new shingle production, as long as any asphalt remaining on the recycled granules does not cause clumping in storage silos or interfere with application equipment.
The major challenge is separating the asphalt from the filler, fines, and fiberglass mat. Whether the process is solvent-based liquid, mechanical pulverization, or a combination of both, remnants of these raw materials will contribute to the total filler content of the new shingles. This can be detrimental to the shingle’s performance properties—such as tear strength—as the preferred filler is substituted by these other materials.
Overcoming Regulatory and Material Limitations
The prescriptive requirements of ASTM D3462 will quickly limit the amount of recycled shingle material because of filler limitations in the finished shingle. The issue of higher filler could possibly be overcome with asphalt improvements or additives, but this is not even an option if roofing stays focused on ASTM D3462.
Polyco has demonstrated that SigmaBond, an advanced asphalt rejuvenator, can help offset the effects of aged asphalt in post-consumer RAS while also addressing higher filler content. SigmaBond incorporates liquefied tire rubber, which enhances the durability and flexibility of asphalt, making it a valuable solution for increasing the use of recycled materials in roofing applications. However, ASTM D3462 remains a barrier, as its prescriptive requirements restrict certain components—such as carbon black and other non-asphaltic materials found in ground tires—limiting the full potential of innovative recycling solutions.
The quotes above are from an article by Mark S. Graham, NRCA’s Associate Executive Director of Technical Services, in Tech Today, July 2013, Alternative asphalt shingle products.
FOR IMMEDIATE RELEASE
Reno, Nevada, October 14, 2024 – Polyco, manufacturer of high-performance, sustainable asphalt solutions for the roofing and paving industries, has named Dario Alvarez as its new Regional Sales Manager. Alvarez brings over 20 years of sales leadership experience in asphalt pavement solutions and highway safety technologies.
His strength lies in introducing customers to emerging, innovative product lines. Throughout his career, Alvarez has worked with several prominent companies in the industry, including Ingevity and Surface Tech, gaining critical experience with asphalt and pavement preservation technologies. These have included polymer modified asphalts, asphalt emulsion, fuel oils, surface sealers, refined products, and preformed thermoplastic pavement markings.
“What’s been fun for me is [that], in a lot of the jobs that I’ve taken on as a sales professional and as a sales leader, [the] product that I’m about to sell is brand new to the industry,” he said. “That’s something that’s really exciting to me. Polyco is offering the same type of adventure where this is a technology that we’ve had for a few years, but it’s still kind of burgeoning in the industry on the paving side.”
In his new position, Alvarez is tasked with developing relationships with specifiers and end users in the asphalt pavement market to promote SigmaBond, Polyco’s waste tire rubber asphalt modifier. “This role affords me a great opportunity to go out and introduce something that could really benefit the paving industry, that is proven to work really well and be sustainable. SigmaBond has got all of the characteristics and attributes that people are looking for.”
Alvarez has the personality, passion, self-motivation, and technical knowledge that compels companies to revolutionize how they do business. He showed this promise from the beginning when, in 2000, he launched his asphalt career selling liquid asphalt in Ogden, Utah, for Pioneer Oil Company.
“My boss [at the time] hired me because I had a really outgoing personality,” said Alvarez. “It was easy for me to talk to people and engage with people and get them to like me. So I got out there, started talking with contractors, getting involved in the industry.”
Polyco looks forward to advancing the asphalt industry with Alvarez on their team.
About Polyco
Polyco is a leader in reducing environmental impact by repurposing waste into high-performing, sustainable infrastructure solutions. Their flagship innovation, SigmaBond, enables asphalt products to be upcycled again and again. Click here to learn more.
As many in asphalt know, we’re a community as much as we are an industry. That’s why Polyco’s latest hire, Dario Alvarez, our Regional Sales Manager, is a perfect fit – he’s about people.
In 2000, Dario launched his asphalt career selling liquid asphalt in Ogden, Utah, for Pioneer Oil Company. “My boss [at the time] hired me because I had a really outgoing personality,” he said. “It was easy for me to talk to people and engage with people and get them to like me. So I got out there, started talking with contractors, getting involved in the industry. For the next seven years, I worked in Idaho, Montana, Utah, and Wyoming, selling liquid asphalt to hot plants.”
From there, his sales career accelerated and he branched out into the highway safety industry, where his passion for people really began to shine. It was Dario’s job to engineer safe work zones that utilized smart work zone system technology and then sell that work zone configuration to contractors to implement. “We’ve got guys out there putting down the roads, putting down the asphalt, building bridges. And, as they are trying to create this infrastructure, they have to be kept safe from the traveling public,” he said.
Over the course of his career, Dario found his way back to asphalt sales. He worked with several prominent companies in the industry, including Ingevity and Surface Tech, gaining critical experience with asphalt and pavement preservation technologies. These have included polymer modified asphalts, asphalt emulsion, fuel oils, surface sealers, refined products, and preformed thermoplastic pavement markings.
Ultimately, asphalt is where he wants to be.
“What’s been fun for me is [that], in a lot of the jobs that I’ve taken on as a sales professional and as a sales leader, [the] product that I’m about to sell is brand new to the industry,” he said. “That’s something that’s really exciting to me. Polyco is offering the same type of adventure where this is a technology that we’ve had for a few years, but it’s still kind of burgeoning in the industry on the paving side.”
Dario has been tasked with developing relationships with specifiers and end users in the asphalt pavement market to promote SigmaBond, Polyco’s waste tire rubber asphalt modifier. “This role affords me a great opportunity to go out and introduce something that could really benefit the paving industry, that is proven to work really well and be sustainable. SigmaBond has got all of the characteristics and attributes that people are looking for.”
Outside of his profession, Dario makes sure to allocate time for personal pursuits, namely fly fishing and coaching judo. Alongside his coaching partner, he runs the largest judo program for juniors in Austin, Texas. It represents yet another way in which Dario connects well with people, who ultimately are what matters most.
Polyco is delighted to announce that Bob Rivers is coming on board as the new Director of Technical Sales for the West of the Rockies region. With over 40 years working in asphalt paving and roofing, Bob brings a wealth of industry experience to his new role. We sat down with Bob to learn more about his background, his journey to joining Polyco, and what he’s looking forward to.
Can you share a little about your background in the pavement industry?
I started way back in 1981 down in Southern California at an independent refining company that produced the complete gamut of petroleum products from fuels to asphalt. I didn’t like the tedious rotating shifts very much, so I went into the laboratory as a quality control tech for a year, testing aviation and automotive fuels, paving and roofing asphalts. I transferred to R&D for a more flexible schedule and went back to school. This role exposed me to all the nuances of the Dark Side of petroleum science — emulsions, rejuvenation agents, oxidized roofing asphalts, felt saturants, bunker fuels, printing inks and more.
Basically, the R&D team enabled the company to make consistent, finished product formulations from a changing refinery crude charge. Much like today’s Polyco lab folks continue to do now. Some things never seem to change. Same challenges, different day!
How did you first get connected with Polyco?
I met Tom Nichols in Stockton, CA in the 1980s when I was marketing the base asphalt for modified roofing products there. Even then, Tom had big ideas and aspirations for entrepreneurial success. We kept in touch through the years, and in 2014, I joined AST as a consultant, helping to market and sell PG asphalt and SigmaBond in California, Arizona and Nevada.
I’ve been in and around the asphalt game for over 40 years now and over 20 in PG-TR development sales. The SigmaBond technology really intrigued me from the start. Many other TR startups promised everything but could not deliver the goods. It is exciting to see the innovation and new technologies we are developing. Unlike other rubber modification processes that degrade the properties and performance when adding more ground rubber, SigmaBond keeps improving the properties at higher rubber dosages. It’s a game-changer, truly unique, and that got me hooked. As pavement experts and academia have said, SigmaBond PG-TR is the future of TR asphalt binder specifications.
As the new sales and marketing lead out West, what’s got you most excited?
Our biggest challenge now is going to be making enough SigmaBond to satisfy the demand we’re seeing! More and more states and agencies are looking to mandate high recycled rubber contents in their asphalt mixes for sustainability. With SigmaBond, we can finally give them those high rubber loads without compromising the pavement performance. That’s been the big issue holding the other technologies back.
Polyco is pioneering the future for higher recycled rubber contents and more sustainable asphalt mixes with SigmaBond. We’ve got a really remarkable opportunity to promote greater sustainability through more recycled rubber while also delivering better-performing asphalt pavements. Polyco has some awesome products, and I’m thrilled to be partnering with Polyco’s technical team to communicate the SigmaBond PG-TR benefits across the West.
Tell us a little about your life outside of work.
While the asphalt industry has been my career passion for over 40 years now, my greatest joys come from life outside of work with my family. I’ve been blessed with a sweetheart of a wife, Lili, for 41 years and three months so far. We’ve got three of the best children and their spouses that you could ever wish for, and they’ve given us four beautiful grandkids. We’re lucky enough to live near the whole family, and watching those little ones grow up is a priceless gift. Though, I will say… It’s great to see their headlights coming up the driveway, but it’s also a relief to see the tail lights when they’re leaving. They certainly have a lot of energy!! Without a doubt, we’ve been blessed!
Lili and I have a couple of mischievous, small but mighty dachshund-chihuahua mixes that keep us on our toes.
After 10 years of my AST consulting internship and now, I am finally a Polyco employee. I look forward to continuing to collaborate with all my new official co-workers. Again, and most seriously, I am blessed!
It’s what’s inside that counts. The quality of a shingle is only as good as the materials it’s composed of — and shingle manufacturers have been put on notice. More accountability is being demanded of the roofing industry, with an emphasis on expanding sustainability measures.
For more than two decades, our roofing partners have relied on our expertise to give them a strategic advantage in the evolving asphalt shingle market. With sustainability at our core, we are helping manufacturers meet demands today while looking toward the future.
Use more recycled materials
There are 41 million scrap tires that end up in landfills every year, according to a report by the U.S. Tire Manufacturers Association. To combat this wasteful problem, we developed the Rapid Digestion Process™. Our patented technology completely liquefies scrap tire rubber and combines the resulting concentrate with asphalt to create performance-enhancing additives. By enabling up to 50% tire rubber in the mix, virtually every layer of a shingle could contain more recycled materials.
Close the loop in the roofing lifecycle
As more manufacturers are taking asphalt shingle recycling into their own hands, RDP can help reduce the burden. When it’s time to replace a roof, the recovered asphalt shingles can be remanufactured with sealants, adhesives and coatings containing liquefied rubber. Using modified shingles made from RAS with waste tires opens up possibilities within a circular economy and further closes the loop in the roofing lifecycle.
Construct more durable shingles
In many regions across the country, sturdy shingles are more than a nice-to-have — they are a requirement. This is especially true for states like Florida, where shingles must be able to withstand the uplift from Category 5 hurricane-force winds. Our roofing solutions have been tested to reduce blow off and resist dents/ridges, tears and granule loss. In fact, many of our roofing partners have received excellent hail impact ratings from the Insurance Institute for Business & Home Safety (IBHS). The measurable performance is a testament to the quality we deliver.
Extend the life of roofs
Engineering longer-lasting asphalt shingles leads to a longer-lasting roof — which benefits consumers, builders and manufacturers. Addressing problems under warranty are costly for contractors and manufacturers, not to mention a hassle for property owners who have to live under a failed roof. By extending the use life of modified shingles, roofs don’t need to be replaced as often — which diverts waste from landfills.
While our roofing partners have taken great strides to stay ahead of the curve, there is much on the horizon. Sustainability will continue to take precedence — with an increasing focus on Environmental Product Declarations (EPDs), LEED (Leadership in Energy and Environmental Design) certifications and reducing our overall environmental impact. As we continue to keep a pulse on the roofing industry, we will push forward with innovations that meet and exceed demands.
To me, building a sustainable infrastructure is a moral obligation. For the foreseeable future, humans will need roofs for shelter and roads for transportation. Asphalt is a core (albeit overlooked) ingredient in both instances. However, the general public has a narrow view of what asphalt is, how it’s used, and what goes in it. I see this as an educational opportunity to unpack the versatility of this material and how it can advance sustainable practices that power a circular economy.
At Polyco, the path to sustainability has evolved over time but always with the same goal in mind: to reduce our environmental footprint by manufacturing products with zero waste. We invested in this mindset through the development of our proprietary Rapid Digestion Process™ (RDP), which breaks down end-of-life rubber tires into a liquefied state. From this process, we developed a performance-enhancing asphalt additive, SigmaBond, that can be blended to create custom asphalt formulations for use in multiple applications. In addition to upcycling tires, SigmaBond further enhances sustainability by enabling the use of more recycled materials (such as recycled asphalt pavements and recycled asphalt shingles) in asphalt mixes, reducing the need to source virgin materials and crude oil. Moreover, SigmaBond’s performance-enhancing qualities extend the lifespan and usability of roads and roofs so they don’t have to be repaired or replaced as often.
Solving the global waste problem is an issue that is too big to ignore. Reusing end-of-life tires in roads and roofs is a step in the right direction. It’s an innovative, clean way to divert rubber tires from landfills or prevent them from being burned for fuel. But our journey to sustainability doesn’t stop there. We still have a long road ahead of us to become a truly green industry within a circular economy. There are so many other materials to experiment with, new processes to try and technologies to deploy that haven’t even been conceived yet. As advancements are made, Polyco will continue to adapt alongside them until we have completely eliminated waste. It’s a lofty goal but one that is necessary to ensure our future is built on sustainable infrastructure.
Polyco’s Supply Chain Manager, Kaylea LaBee, is a dedicated problem-solver who thrives on new challenges. Starting as an assistant in 2014, Kaylea moved into customer service before recently transitioning to head up Polyco’s supply chain operations. We spoke with her about her evolving career, the excitement of bringing a fresh perspective to the field, and her vision for greener production practices.
What does a typical day look like at Polyco now that you’ve taken on a new role?
I’m our supply chain manager now, so I keep an eye on everything that comes up on the supply side. Every morning, I’m responding to emails, placing orders with raw material vendors, providing forecasts, securing logistics, and monitoring markets for pricing trends. It keeps me on my toes! I’m also getting another degree—this one in supply chain management from Western Governors University—so I’m pretty busy these days.
What do you like most about working at Polyco?
The people! We’re a tight-knit group, and I have a good relationship with team members at all levels. Being able to joke around and have some laughs throughout stressful days makes work really enjoyable. I’m grateful for the support I’ve had from everyone in transitioning to this new position.
What excites you most about the future of your role and the asphalt industry?
I’m seeing the industry focus more on sustainability and green initiatives. My generation cares deeply about environmental impact, so I’m excited that I get to help develop cleaner technologies and production methods with Polyco. Things like finding uses for recycled tires align really well with my values. I’m also making great contacts at industry conferences and traveling more in my new role. Growing my network and seeing operations firsthand is incredibly valuable.
Why is sustainability important for Polyco?
The world is shifting toward more eco-friendly options across industries. Polyco demonstrates care for the planet’s future by developing quality, sustainable products. I know we have a lot of staff with children who want to build a cleaner world for the next generation. Our commitment to reducing waste makes me proud to work here.
What do you love to do outside of work these days?
Between work, school, volunteering at the local animal shelter, and spending time with my boyfriend, my free time is really limited! But I treasure weekends relaxing with my dog Ophelia, hiking, and trying new things. My boyfriend recently got me into disc golf, and I’ve been trying my hand at old-fashioned golf-golf, too! When I can find a quiet morning, I like listening to music while watering my 50 (!) houseplants. Botany is definitely a lifelong passion for me. Simple joys!
