A journey of faith, science and humanity: Chris Macosko wins 2023 Charles Goodyear Medal

WARRENSVILLE HEIGHTS, Ohio—Perhaps the greatest scientist who ever lived, Isaac Newton, believed in intelligent design, working his entire life to demonstrate that the union of science and the divine was not an either/or proposition.

The 2023 Charles Goodyear Medal winner, Chris Macosko of the University of Minnesota, has embarked on a similar quest, one that has been informed by his faith and lifelong study of rheology—ironically, the branch of physics that deals with the non-Newtonian flow of liquids.

"The last 50 years have been great," Macosko told Rubber News April 26, following his acceptance speech for the Charles Goodyear Medal at the spring meeting of the ACS Rubber Division. "I continue to maintain a love for rheology. But what drives us in understanding science is the creator of things.

"And it is fun to discover a little bit of what God put into our world."

To hear Macosko speak is to realize what science sounds like.

To hear Macosko's students and colleagues speak about him is to realize what one person's humanity can inspire.

"When I saw that he won (the Charles Goodyear Medal), I thought, I know that guy," said Kathy Perevosnik, a senior engineer at Tenneco's Clevite Elastomers Group, who attended the gathering. "I turned around and glanced at the rheology textbook he authored on my book shelf.

"He is just such a good person. He pushed the world of rheology further, but he will be remembered for who he was as a person."

Some of the best and brightest in the rubber industry gathered in Northeast Ohio April 25-26, as the ACS Rubber Division hosted its 203rd technical meeting.

Highlighting the awards portion was Macosko, honored for his extensive and groundbreaking work in developing basic relations for crosslinking polymerization.

His work in this field remains a foundation for research today.

"Thank you, and thank you to HF Mixing Group (sponsor of the award)," Macosko told a packed ballroom at the Marriott Cleveland East. "I'm really humbled to receive this award.

"I challenge all of you to Google the (Charles) Goodyear Medalist winners and look at the names—it is like an exam in polymer chemistry or polymer physics—and many of you will recognize the equations you had and the people you studied from."

Macosko himself attended his first ACS Rubber Division meeting in 1972.

The purpose of the Charles Goodyear award is to perpetuate the legacy of the man who discovered vulcanization, the process that makes rubber usable. The medal—the highest honor given by the technical association— is awarded to someone who has "significantly changed or contributed to the rubber industry" for the better.

Macosko also has conducted pioneering work in the areas of molecular weight and viscosity, branching, crosslink network formations, crosslink densities, swelling and sol fraction.

He is credited with developing the first commercial mechanical spectrometer. And his work influences a broad range of polymer processing operations, including reaction injection molding, extrusion, melt blowing and coating.

The Princeton-educated chemical engineer co-founded the company Rheometrics (a company that later became TA Instruments) along with a fellow graduate student, and he is the author of more than 50 publications—including Perevosnik's aforementioned industry standard textbook, "Rheology: Principles, Measurements and Applications."

Macosko even teased that a second edition of the book is in the works—a continued academic passion for which he will have more time in semi-retirement.

"I've always wanted to write a second edition of 'Rheology,' " Macosko said. "Now we are finally assembling it. We will get out a draft this year, then by later in 2023 it could be published."

Macosko's other accolades, among many, include winning the Stein Award in Materials from the American Institute of Chemical Engineers, the International Award of the Society of Plastics Engineers and the Bingham Medal of the Society of Rheology.

He was the winner of the Pall Award for Applied Polymer Research in 1997 and the Fernley H. Banbury Award from the ACS Rubber Division in 2006.

The Rubber Division first offered the Charles Goodyear Medalist award in 1941, an inaugural honor that went to David Spence, a researcher noted for synthesizing isoprene for use in synthetic rubber.

Last year's co-winners were Tim Rhyne and Steve Cron, retired Michelin North America Inc. engineers who were recognized for their work in developing the Tweel, a non-pneumatic tire with a polyurethane-spoked wheel.

While Macosko may have been honored with the prestigious award for his scientific prowess, his selflessness in "paying it forward" led him to give back the monetary award that came with the Charles Goodyear Medal.

Macosko recently donated the entirety of the $7,000 from the award to the CEMS (Chemistry, Engineering, Math and Science) Chris and Kathleen Macosko Fellowship match at the University of Minnesota.

"Words cannot do enough justice to describe the breadth and depth of Professor Macosko's work and its global impact in the rubber and plastics industry and academia," said Maria Ellul, a retired principal scientist with ExxonMobil Chemical Co., in her letter of support for Macosko. "He is a most qualified candidate (and) is most deserving of this honor, which is now long overdue."

Macosko is a product of the Midwest, the son of a Carnegie Mellon-educated father, also an engineer, and a mother who worked part time as a nurse.

"But with five kids, she stayed pretty busy at home," Macosko said.

He was the oldest of the four brothers and one sister.

The Macosko clan grew up in Berea, Ohio, a small Cleveland suburb that sits to the west of downtown today, near Cleveland Hopkins International Airport.

Born in 1944, Macosko graduated in 1962 from Berea High School, where a fascination with chemistry was instilled in him at an early age.

"They had very good chemistry and physics teachers at the high school. The word 'chemistry' just jumped off the page at me," he said. "When I was in middle school, I was disappointed that you couldn't enter the science fair until ninth grade.

"But it was a great town to grow up in, a community that watched out for you."

The professor emeritus at the University of Minnesota spent many cold evenings off the shores of Lake Erie in the heated family garage, where his father "nurtured, supported and encouraged" Macosko's love of chemistry.

At the time, that included homemade formulas for cherry bombs and what some might call "aftermarket" rocket fuel.

"Before Estes (Model) Rockets came along, you had to make your own fuel," he said. "I suppose I could've blown my hand off, but kids are always looking for the big bangs, the power, the loud stuff."

As Macosko tells it, he and his father mixed sugar and potassium perchlorate for the propellant, but they still needed an ignition source.

"And the battery on the family car worked just fine," he said.

"All of this really reflects the interest in science that burned in me in my youth."

As it turns out, Macosko also would find interest in a different Big Bang later in life, as he continued to pursue the Newtonian tenet that both nature and a creator seek the simplistic over chaos, truths over falsehoods.

Macosko earned his bachelor's degree in chemical engineering from Carnegie Mellon University in 1966, where his granddaughter now is a fourth-generation student in the family.

He obtained his master's degree and doctorate in chemical engineering in 1970 from Princeton University, where he worked under the supervision of industry icon Bryce Maxwell.

"There was a future in plastics—and it was me," Macosko said. "I ended up at Princeton and found one of the only guys working in plastics at the time, and that was Bryce Maxwell."

Specifically, Maxwell is credited with authorship of a groundbreaking paper on "the nature and kinetics of crazing on atactic polystyrene; and his development of a new mechanical spectrometer with a (specific) frequency range."

"We developed a lot of creative ideas and experiments, including the eccentric rotating disc rheometer," Macosko said. "To get certain analytics, you had to use a tortion pendulum, measuring force in opposite directions.

"My thesis was to understand how this thing worked, then compare that to more traditional methods."

Macosko noted that there was an ulterior motive in continuing his schooling between undergraduate and graduate school.

"If you did not stay in school, you would have been drafted into the (Vietnam) war," he said.

His time in grad school saw his initial and brief foray into the humanities, serving as a reporter for Steel Magazine, an industry trade publication.

"I was a pretty good writer," he said. "I was a kid reporter who got to go into the labs and interviewed people. What I found was that I enjoyed being in the lab more than I enjoyed being in front of a typewriter."

Not long after stints with ExxonMobil and other companies, he found his way to Minnesota, where he and his wife, Kathy, appreciated both the weather and values, neither of which were so different from Berea.

"We really liked Minnesota," he said, adding that he took sabbaticals with research grants to other schools such as MIT and Northwestern. "Publishing your work is crucial."

With all of his accomplishments, Macosko—and indeed, his students—counts his relationships with people as one of his most important callings.

Advising, teaching and affecting a younger generation in such a positive way has come full circle for Macosko, as he has published many research papers with both his name and his students' names as bylines.

"This career of 50 years has been really exciting," he said. "With 90 Ph.D students and 50 post-docs, still I get to connect with students today. It has really been fun."

Macosko said he became a Christian after three or four years in Minnesota.

"And I realized that you have a responsibility to care for people," he said. "It is like Psalm 19 that Newton would cite: 'The heavens declare the glory of God; the skies proclaim the work of his hands.'

"I never really faced the question of reconciling science with faith, though I did begin studying evolution, and even received a Templeton (Foundation) Grant to do so. I taught classes on the origins of humans, morality, science ... and asked, 'is this by chance or by design?'

"One of my students raised his hand and asked, 'what was before the Big Bang?' And there is no data there to use."

He concluded his April 26 presentation by offering a graphic of a family tree with all the names of his doctorate, master's and post-doc students on it.

The tree was at least four rings, or four generations, deep.

One of the branches was in the audience, Ica Manas, a professor at Case Western University who completed her post-doctoral work with Macosko.

Manas, in turn, was one of Perevosnik's professors.

And now Perevosnik is mentoring Kelly Briceno, a Venezuelan woman who works in Denmark with Lego.

Twenty years ago, Macosko responded to a question that Briceno and a fellow student had regarding a scientific paper—and it left an indelible impression.

"The tree trunk of all the people he has touched is so meaningful," Perevosnik said. "I wanted to share this continuing story of how our Goodyear Medalist touched the lives of two young women in Venezuela 20 years ago, to such a huge extent—because he cared, not just because he's a great scientist."

Reached in Denmark, Briceno was eager to share a comment on her arms-length idol.

"That is the face of a successful man, not only successful in his career but as a human being who didn't hesitate to help two undergraduate students from an underdeveloped country more than 20 years ago," Briceno said in an email to Rubber News. "He has made two students very happy."