Related Experiment Video
Updated: Jul 26, 2026

Biological Compatibility Profile on Biomaterials for Bone Regeneration
Published on: November 16, 2018
Free volume and mechanical properties of Palacos R bone cement
J Algers1, F H J Maurer, M Eldrup
1Polymer Science & Engineering, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden.
Abstract:
The free volume and the mechanical properties of Palacos R bone cement were determined from positron annihilation lifetime spectroscopy (PALS) and from dynamic mechanical thermal analysis (DMA) in the temperature ranges 24-220 degrees C and 30-120 degrees C, respectively. The heating of bone cement caused an appreciable reduction of the free volume, measured as a decrease in the ortho-positronium lifetime tau(3) from 2.04 to 1.91 ns, as well as a clear increase in the storage modulus from 2.3 to 3.0 GPa. The changes in free volume and storage modulus after the heat treatment were interpreted as an effect of elimination of residual monomer from the bone cement. The free volume of the bulk-polymerized phase of bone cement was estimated from a simple difference method, suggesting that the residual monomer was eliminated from the bone cement between 60 and 90 degrees C, thus implying a glass transition temperature of only 60 degrees C for the bulk-polymerized phase. The spherical free volume cavity size estimated from the ortho-positronium lifetime V(tau(3)), and the storage modulus E'(storage) from DMA measurements were found to correlate by a linear relationship throughout the studied temperature range, and the correlation appeared to be independent of the presence of residual monomer.
More Related Videos
Related Concept Videos
Mortar Properties
Fineness of Cement
Direct...
Soundness of Cement
Porosity in Cement Paste
The balance of water to cement in the mix is critical—it...
Total Voids in Concrete
Pore Size Distribution
Adequate...

