It's been said that petroleum is too precious to simply burn, and indeed the myriad plastics derived from oil make life hard to imagine without them: computer components, automobile dashboards and fenders, credit and identification cards, sports gear and clothing, carpeting, and anti-glare and anti-shatter coatings for glass. At age 84, Vandenberg is one of the pioneers of the field.
The polymer chemist is perhaps best known for his independent discovery of a strong, hard, impervious form of polypropylene, the plastic that makes dishwasher-safe food containers and water-resistant outdoor carpets. Called isotactic polypropylene, this plastic was also discovered in 1954 by Italian chemist and later Nobel Prize winner Guilio Natta.
At the time of his discovery Vandenberg was a research chemist at Hercules, Inc., a chemical company whose products manufacturers use to thicken paints and make paper, specialty adhesives, and other products. He started work at the Wilmington, Del.-based company in 1939, studying the chemistry of papermaking, and — except for a brief stretch in the 1940s to work on smokeless powder for the war effort — stayed for 43 years.
"By my senior year in high school, I had a strong resolve to become a chemist. In fact, my life goal in the yearbook was 'to be a good chemist,'" he remembered. "This was 1935, in a country still recovering from the Depression."
At Hercules Vandenberg also developed ways to form isotactic polypropylene, and his pioneering work allowed the company to become the first and later its largest producer. The trick is in its construction: the stringing together of individual units of propylene, a three-carbon molecule derived from petroleum. Two of the carbons link up with those of other units to form a chain, while the third of each unit juts up above or below.
If the third carbon is randomly placed on either side of the chain, the resulting polypropylene is soft and rubbery. Vandenberg discovered construction methods that always place the third carbon on the same side. With one side of the chain bulkier than the other, isotactic polypropylene bends into uniform coils that can pack together. The result is a polypropylene form with the same chemical formula as the randomly placed carbons but with dramatically different properties. Its crystalline structure does not melt in boiling water; it has the ability to form stiff, sturdy fibers; and it has a resistance to solvents and other chemicals.
To compel the third carbons to consistently stay in the same position, Vandenberg designed a variety of catalysts, the exquisitely orchestrated construction workers of chemistry. Over succeeding decades he refined that knowledge with new discoveries. Among them were ways to control the length and branching of polymer chains, as well as what is now the most common route to make phenol, a chemical used to make products as diverse as plywood, automotive components, epoxy resins and disinfectants.
Vandenberg grew up in the years between World War I and II in Hawthorne, N.J., where his father owned a feed store. As a boy he was intrigued by the violin as well as chemistry, studying music in school while running experiments of his own in a home laboratory.
After retiring from Hercules in 1982 Vandenberg joined the faculty of Arizona State University. In the last dozen years his research achievements have taken a new turn: polymers that have biomedical applications, particularly for implants, a collaborative project with ASU bioengineer Vincent Pizziconi.
Typically, bioengineers must consider two key engineering elements when developing biomaterials, according to Pizziconi. The materials must have mechanical properties that allow them to be shaped into the desired device — such as a tube for use in an artificial blood vessel. And the materials need to be engineered so they are compatible with living tissue and do not cause adverse reactions, such as an inflammatory response.
Vandenberg has developed a new class of biomedical polymers and the means to tailor them for a wide range of medical devices, including flexible scaffolding for a blood vessel or load-bearing orthopedic implants.
"Over the years we've been able to synthesize several promising biomaterial candidates," said Pizziconi. The researchers are in the process of scaling up and hope to "get a better feel" for the properties of the materials and how compatible they are with biological tissue.
Vandenberg received his undergraduate degree in 1939 from Stevens Institute of Technology, which also conferred on him an honorary Ph.D. in engineering in 1965. He has received several other awards for his work, including the ACS Award in Polymer Chemistry in 1981 and the ACS Award in Applied Polymer Science in 1991. Over the years he has been very active in the ACS division of polymer chemistry and served as its chair in 1979.