The nonlinear, anisotropic, and multiscale mechanical behavior of knitted textiles is investigated experimentally in this article. The approach is motivated by recent computational work by the authors that revealed, for the first time to their best knowledge, local‐global mechanical behavior effects related to the hierarchical, three‐dimensional structure of this type of materials. The investigation is carried out on single jersey knitted textile specimens. Mechanical testing consisting of tensile loading along the two principal directions was coupled with a noncontact, optical metrology method capable of providing deformation measurements. The effect of globally applied loading on yarn‐to‐yarn interactions was explored using measured data. The results validate the previously obtained computational findings that include the anisotropic behavior between course and wale directions, the pronounced out‐of‐plane motion observed when in‐plane loading is applied, as well as the characteristic nonlinear mechanical behavior of knitted textiles. These effects were linked to direct observations of the loop structure that demonstrated the coupling between local kinematics and kinetics with global mechanical behavior.

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In this study, artichoke stem particles (AS) and wollastonite mineral (W) were used as an organic and inorganic fillers in order to improve the mechanical properties of polypropylene (PP). In this regard, PP-based composites containing AS and W were produced as non-hybrid and hybrid materials using a high-speed thermokinetic mixer. Mechanical properties of polymer composites were investigated by the tensile test. Experimental results reveal that the highest elastic modulus for PP-W and the highest tensile strength for PP were obtained while the lowest ultimate strain value was gained using PP-W-A. Then, multiple nonlinear regression analysis was employed to determine the effect of weight ratios of wollastonite mineral and artichoke stem particles in polypropylene on elastic modulus, tensile strength and ultimate strain. Experimental results were expressed second order (tensile strength), third order (elastic modulus) and fourth order (ultimate strain) mathematical models. The results show that the proposed models have well fitted with the experimental results. The coefficient of determination (R2) values were found between 0.95 and 1 in all models. Also, boundedness check control of the proposed models which gives information about whether models are realistic or not was carried out by calculating the maximum and minimum values produced by the relevant model.

In this research, artichoke stem particles (AS) and wollastonite (W) were used as an organic and inorganic fillers in order to improve the mechanical properties of polypropylene (PP). In this regard, PP-matrix composites containing AS and W were produced as non-hybrid and hybrid using a high speed thermo-kinetic mixer. Mechanical properties of polymer composites were investigated by the tensile test. Experimental results reveal that the highest modulus of elasticity was obtained in PP-W and the highest tensile strength was obtained in raw PP while the lowest ultimate strain value was obtained in PP-W-AS. Then, multiple-nonlinear regression analysis was employed to determine the effect of weight ratios of W and AS in PP on modulus of elasticity, tensile strength and ultimate strain. Experimental results were expressed with polynomial, rational and trigonometric models. The results show that the proposed models have well fitted with the experimental results. The coefficient of determination (R2) values were found between 0.95 and 1 in all models. Also, boundedness check control of the proposed models which gives information about whether models are realistic or not was carried out by calculating the maximum and minimum values produced by the relevant model.