Effect of Hemp Fiber Addition on Mechanical Properties of Acrylic Resin: Coupled Experimental and Theoretical Study

We present experimental and theoretical study of the fiber-matrix composites based on polymethyl methacrylate (PMMA) prosthetic material. Hemp fibers of different lengths and concentrations were added to PMMA. In total, ten groups of composite samples were prepared. Flexural strength test was performed for each sample. We found that the addition of hemp fibber significantly change the mechanical properties of pristine PMMA. The nature of the interaction between PMMA and hemp fiber were further investigated with scanning electronic microscopy, infrared spectrometry and density functional theory. This interaction were described atomistic level in terms of quantum descriptors of reactivity, such as chemical potential, electronegativity, chemical hardness and softness, electrophilicity, electrodonating and electroaccepting powers and electrons transfer. We observed the formations of strong hydrogen bonds between the matrix and fibers, which explain the observed improvement of mechanical properties.