Preparation method of high-hexene grafted high-density polyethylene geomembrane blow molding material

Abstract

The invention discloses a preparation method of a high-hexene grafted high-density polyethylene geomembrane blow molding material. The method comprises the following steps: (1) when a diluting agent is always under a circulation state, placing monomer ethylene and 1-hexene in a reaction vessel; adding an antistatic agent and an catalyst subjected to an activation treatment; adjusting the reaction temperature in the reaction vessel to 92-98 DEG C until the melt flow rate of a reaction product is 10.0-13.0g / 10min and the density of the reaction product is 0.937-0.939kg / m<3>, thereby obtaining ethylene-hexene polyethylene copolymer base resin with weight average molecular weight of 200,000 to 300,000, 1-hexene content of not less than 1.20% and crystallinity of 46.5-49.5%; (2) uniformly mixing 99.5-99.8 parts of the ethylene-hexene polyethylene copolymer base resin and 0.20-0.50 part of an antioxidant; and adding the mixture to a mixer for extrusion granulation, so as to obtain the geomembrane blow molding material. According to the method, a high-activity novel chromium catalyst is adopted, the equipment limitation of a loop slurry process is overcome, and high-hexene grafted high-density polyethylene is produced. With the method, reaction scale is effectively ameliorated, a reactor wall attachment phenomenon is reduced, production is smooth, and the productivity of the special material is high.

Description

technical field [0001] The invention relates to a geotechnical film blowing material, in particular to a geotechnical film blowing material grafted with high-hexene high-density polyethylene. Background technique [0002] High-density polyethylene geomembrane is a new type of anti-seepage material with high anti-seepage coefficient. It can be used alone as an anti-seepage material or combined with non-woven fabric to make a composite anti-seepage membrane. High-density polyethylene geomembrane has good heat resistance, cold resistance, and aging resistance. When used, it is not limited by the ambient temperature of the area. It can be used exposed for a long time while maintaining the original performance. If it is buried and laid, the service life longer. [0003] Compared with advanced countries in the world, the application of geomembrane materials in my country started relatively late. At present, the high-density polyethylene geomembrane materials commonly used in the...

AI Technical Summary

Problems solved by technology

However, the high-density polyethylene is produced by the loop slurry process. Since the reaction system is a slurry system, when a high concentration of 1-hexene monomer is introduced, the reaction system is likely to be sticky and the reaction is prone to fouling.

The phenomenon of reaction scaling refers to the phenomenon that the viscosity of the reaction system is too high, and it is easy to stick to the wall, so that the actual temperature of the reactor becomes higher, which obviously deviates from the set value, and at the same time, due to the inability to dissipate heat due to the heat of reaction, the temperature of the jacket water decreases. Lawrence Pump Power Sudden Increase, Response Fluctuates

However, after the reaction scaling occurs, it is easy to gather violently during production, and the production is difficult to control

Therefore, it is very difficult for the geomembrane special material produced by the loop pipe slurry process to break through 0.939g / cm 3 The lower limit of the density

A large number of transition material products are prone to appear during production, which reduces the conversion rate of special materials and reduces output

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