New, tough material is created

MANCHESTER, England, March 10 (UPI) -- British scientists say they have combined chalk and polystyrene to produce a tough new material that could make other materials more durable.

The team of scientists from the Universities of Manchester and Leeds said their technique could be used to make ceramics with high resistance to cracking -- which could, in turn, be used in crack-resistant building materials and bone replacements.

"The mechanical properties of (sea) shells can rival those of man-made ceramics, which are engineered at high temperatures and pressures. Their construction helps to distribute stress over the structure and control the spread of cracks," said Stephen Eichhorn of the University of Manchester. "Calcium carbonate is the main ingredient of chalk, which is very brittle and breaks easily when force is applied.

"But shells are strong and resistant to fracturing, and this is because the calcium carbonate is combined with proteins which bind the crystals together, like bricks in a wall, to make the material stronger and sometimes tougher. We have replicated nature's addition of proteins using polystyrene to create a strong shell-like structure with similar properties to those seen in nature."

Although further study and testing is needed, he said the research "offers a straightforward method of engineering new and tough chalk-based composite materials with a wide range of useful applications."

The study appears in the journal Advanced Materials.