Tensile characteristics for a class of polymeric blends (PP + PA6)

[摘要] This paper presents the influence of component concentration of a class of polymeric blends with different concentration of PP and PA6 and a constant concentration of additives (CaCO3, LDPE and an adhesive) Young's modulus does not have a clear tendency of depending on PA6 concentration and testing speeds, but performs in a band between 1500...1900 MPa, except for the value for PA6 at the lowest testing speed (v=10 mm/min), that is 1454.8 MPa. Under large testing speeds, there were cracks or voids towards the loading direction, forming large parallel 'empty channels'. Investigations are done on possible causes of these longitudinal voids in order to clear if they occur during molding or/and during testing and to eliminate them. Except for values at low testing speed, the average values for tensile stress at break perform in a band of less than 8 MPa. The elongation at break is less than 10% for all materials, except for PA6 at the lowest testing speed, when the highest value for this characteristic was obtained. The lowest values were obtained for material with 20% PA6. For blends with 60% and 80% PA6, the difference between values, at the same testing speed, is the smallest. Energy at break has a slightly increase with the concentration of PA6. From the mechanical point of view, among the formulated blends, material D (with 80% PA6) is the most promising as has the highest stress and energy at break (11.43 J at v=10 mm/min and 8.7 J at v=1000 mm/min), but values are still less than those for PA6.

[发布机构] Department of Mechanical Engineering, Faculty of Engineering Dunarea de Jos University, Galati, Romania^1;National Institute for Aerospace Research Elie Carafoli INCAS, Bucharest, Romania^2;ICEFS COM Savinesti, Romania^3

[效力级别] 材料科学

[关键词] Average values;Component concentration;Elongation at break;Loading direction;Mechanical points;Polymeric blends;Tensile characteristics