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High density polyethylene (HDPE) is a wide variety of sources, low price, good comprehensive performance general-purpose plastics. However, close to the solubility parameter with the majority of hydrocarbon type organic solvent because of its non-polar polymers, and thus resistant to the poor permeability of the organic solvent, and nylon (PA) performance, good oil resistance. HDPE blended with PA alloy was prepared, not only can improve the performance of HDPE in the penetration of the organic solvent-resistant, but also can improve the mechanical properties of the HDPE, which is conducive to further broaden the fields of application of the HDPE. But both polar differences so that the compatibility is poor, need to join the compatibility agent to improve its compatibility. In this thesis, HDPE-g-MAH as compatibilizer HDPE / PA / HDPE-g-MAH blends were prepared. Using a scanning electron microscope (SEM), the capillary rheometer, the X-ray diffraction (WAXD), differential scanning calorimetry (DSC) and polarized light microscopy (POM), etc. The mechanical properties of the HDPE / PA barrier materials, barrier properties, morphological structure, rheological properties and crystal properties. Study HDPE/PA6 of two different blends in HDPE/PA11 PA types of HDPE / PA blends barrier material. Research results show that the preparation conditions and mechanical properties of blend system of HDPE/PA6, shear rate to be around 92S-1, sample temperature should be controlled at about 220 ℃, to the morphology of the modified component distribution of PA in HDPE into a layered structure by droplet. In the compatible agent content (HDPE-g-MAH/HDPE = 5%) of the same conditions, with the increasing content of PA, tensile strength, impact strength emerged first increases and then decreases in PA content was 15%, tensile strength, and impact strength to reach the highest point. In the nylon content w (PA / HDPE) = 5% under the same conditions, for PA6 Blends, when the compatibilizing agent content is around 10%, the tensile strength of the blends, the highest impact strength; while PA11 Blends, the compatibilizing agent content is between 2% to 5%, the tensile strength of the blends, the highest impact strength. PA content of the impact of the barrier properties of the blend, in the amount of the compatibilizing agent under conditions of 15% PA6 used in an amount of 15%, the barrier properties compared to the pure HDPE 2.58-fold increase; PA11 amount of 10%, the barrier properties 1.97-fold increase compared to the pure HDPE. Meanwhile, in the barrier properties HDPE/HDPE-g-MAH/PA11 = 100/5/2 to achieve the best can be seen from the SEM observation, PA overlapping continuous lamellar structure dispersed in the HDPE resin. The study found that the rheological behavior of the barrier material, HDPE / HDPE-g-MAH / PA barrier material for pseudoplastic fluids exhibit shear thinning phenomenon. With the addition of compatibilizing agent, HDPE / PA enhanced sensitivity of the system on the shear rate; simultaneously with increasing the content of the compatibilizing agent, HDPE/HDPE-g-MAH/PA11 apparent viscosity decreased, compatibility agents the content of 2%, the apparent viscosity of the largest; while HDPE/HDPE-g-MAH/PA6 system is the apparent viscosity of showing the overall trend of increased and then decreased compatibilizer content of 8%, the apparent viscosity of the largest. HDPE / PA activation energy of the viscous flow of the barrier material with the compatibilizing agent added as a whole on a downward trend, the temperature sensitivity of reduced and thus a wider processing temperature can be selected in the process, easy molding. By DSC isothermal crystallization of HDPE and HDPE / PA barrier material non-melting behavior, study results showed that, compared to HDPE / PA melting and crystallization temperature of HDPE was increased; With compatibilizer (HDPE-g- MAH) content increases, the melting enthalpy of the blend first increase and then decrease, i.e. the content of the compatibilizing agent is 2%, HDPE/PA6 maximum exothermic enthalpy melt blend, degree of crystallinity, also reaches a maximum, which barrier properties optimum point coincides, the greater the Statements HDPE/PA6 Blends degree of crystallinity, the more contribute to the formation of the barrier layer, more effectively reduce permeability, improve the barrier properties. HDPE matrix from the comparison of different systems of PA6, PA11, PA, have shown of HDPE the PA melting peak close to each other; well in HDPE / HDPE-g-MAH / PA blends, the the PA melting peak and crystallization peak disappears the phenomenon PA types of HDPE / PA blends are the same.
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