Preparation And Performance Study Of Barrier Material PE/EVOH

The technology of blend is mature and simple. Ultimately, blend has good comprehensive performance, the barrier property for water vapor or oxygen and other non-polar small molecules is very high, mechanical properties just change a little. Blends is already become the research focus in the field of packaging materials.Improve the compatibility, means to improve the two incompatible polymers compatibility by adding compatibilizer to. Based on this, use HDPE and EVOH as the two main raw materials, and select the initiator and other additives. Preparative the barrier materials which mechanical properties and barrier properties are excellent, then, Study the ratio of the main raw material and compatibilizer selection and usage amount and other areas.First, study on the preparation technology of compatibilizers.Selective maleic anhydride and high-density polyethylene, glycidyl methacrylate and high-density polyethylene as the two main raw materials of compatibilizer, by adding initiator and second monomer, use melt extrusion technology, get two kinds of graft copolymers as compatibilizer. According to the chemical titration, determine the grafting of various compatibilizer; and select two excellent compatibilizer from both series of compatibilizer, respectively, The results show that; The results show that, by changing the initiator and the second monomer usage amount, two types of compatibilizers are able to obtain higher grafting yield.Secondly, study on high density polyethylene and ethylene/vinyl alcohol copolymer mass ratio.By using the same kind of compatibilizer, and adding the same amount of the compatibilizer, change the mass ratio of the main raw material, melt extrusion samples of blend, then, use the scanning electron microscope to observe the two main raw materials dispersion in the samples of blends, determine the best mass ratio. The results show that, when high density polyethylene and ethylene/vinyl alcohol copolymer mass ratio is 4:1, two-phase of blends is evenly distributed.Finally, study on the usage amount of compatibilizer, at the same time, compare the two compatibilizer on the blend compatibility of the improvement effect. Using compatibilizer which has high grafting rate, add to the main raw material according to designed scale, then, use the method of extrusion melt blending, And made the blends be mold. Used the scanning electron microscope to observe the compatibility of blend, then, tested the blends barrier of oxygen and Organic solvents, at last, tested the basic mechanical properties of blend.The results showed that:compatibilizer could obviously improve the compatibility of blends. Compared with the HDPE, used a certain amount of compatibilizer, the impact strength of blends can increase 61 percent, at the same time, tensile strength only 15 percent decline, the melt flow rate fell about 7 percent. The barrier properties improved significantly also, barrier property of Oxygen increased nearly 30 times, absorption of p-xylene reduced by 72 percent...