E. I. duPont de Nemours & Co. announced yesterday what it called a "breakthrough" in polymer technology that will allow creation of new kinds of plastics and coatings for industrial use.

The new "group transfer polymerization" technique, said DuPont spokesmen, would initially be used to help apply paints and finishes for the automobile and boating industries. The estimated market for such "high performance" coatings is between $5 billion and $6 billion, sources said.

Polymers are chains of organic molecules with special properties that are woven together to create plastics and plastic-like materials. Polyester, the popular clothing fabric, is an example of a commercial polymer.

"This gives us a new tool for building polymers," said Rudolph Pariser, who directs DuPont's polymer research. "It's like finding a new way of putting together houses."

Essentially, the group transfer technique gives scientists greater ability to design polymers with specific properties of strength, flexibility and heat resistance, for example. In the case of automobile coatings, it is possible to tailor a thinner polymer layer and still meet "high performance" requirements.

The group transfer polymerization technique enables manufacturers to "target" monomers--the building blocks of polymers--to specific spots along the polymer chain, thus defining its length and much of its material properties.

In essence, asserts DuPont, the technique provides "unprecedented control in the architecture of unique polymer structures unattainable by established . . . techniques."

In addition to the finishings market, Richard Quisenberry, DuPont's director of Research and Development for Finishes and Fabrication Products Department, said the company would look to the semiconductor industry to see if the technique could be applied to the fabrication of silicon chips. DuPont may also be talking with Western Electric, the manufacturing subsidiary of American Telephone & Telegraph Co., to see if group transfer polymerization could provide coatings for the company's fiber optic technology, industry sources said.

However, the most significant applications of polymer technology, say Defense Department sources, may come in "composite" materials and so-called "polymer ceramics." The Pentagon is currently funding research in materials science that would use enhanced polymers as direct substitutes for metals such as steel and aluminium. Reportedly, enhanced polymers could have the toughness of metal at only a fraction of the weight. Consequently, the military is exploring such materials for vehicles such as tanks, aircraft and personnel carriers.

DuPont's Pariser said DuPont is also looking into composite materials technology and that the new technique for synthesizing polymers should play a role in the future evolution of the materials.