Dynamic Mechanical Analysis of Viscoelastic Properties of Softwood and Hardwood as a Natural Polymer Material

The dynamic mechanical analysis using low-amplitude harmonic oscillations in addition to the main quasi-static load was employed to determine the storage modulus E ', the loss modulus E ", and the mechanical loss factor tanδ. A comparative description of the static and dynamic viscoelastic properties of softwood (pine, spruce, and larch) and hardwood (oak, linden, and birch) species common in the Russian Federation was presented as a function of the frequency of the probing oscillations and the stress of the quasi-static load. The contribution of different frequencies to the overall viscoelastic response of softwood and hardwood was determined, and the effect of the additional oscillating load on the dynamic parameters of wood was estimated.