The modified method of by-product polyethylene wax (PEW) of high density polyethylene production process has been studied,the result indicated that via catalyzed oxidation and maleic anhydride (MAH) grafting,the by-product PEW can produce carboxyl group or MAH polar group on the polymer chain,that can enhance the application value of the PEW greatly. By the air catalystic oxidation,when the oxidation temperature is 145 ～ 155 ℃ ,the air speed of flow is 5 ～ 6 m/s,the amount of duplicate match catalyst (M_1: M_2 = 1: 1) is 0. 4%～0. 5% ,the duration of oxidation is 6 h,the faint yellow oxidized polyethylene waxes which the acid value is 24.0 ～27.0 mg KOH/g can be obtained. By MAH grafting, at the optimum condition:reaction temperature 155℃,reaction time 5 h,the amount of initiator 2.0% , the amount of MAH 5% ,the grafted PEX which the acid value is 48.30 mg KOH/g can be obtained. By extrusion grafted, uses the automated continuous production method, at the condition of extrusion temperature 80 ℃～90℃, rotational speed 30 r/min, torque 0 ～ 4 N·m, and the amount of initiator and MAH respectively is 2.0% and 15% ,the acid value of product is 17.6 mg KOH/g.%高密度聚乙烯生产过程中副产聚乙烯蜡,采用空气催化氧化法和马来酸酐接枝法均可在聚合物分子链上生成羧基或马来酸酐极性基团,可大大提高聚乙烯蜡的应用价值.采用空气催化氧化法,氧化温度为145～155 ℃,空气流速为5～6 m/s,复配催化剂(M_1∶M_2=1∶1)量0.4%～0.5%,连续氧化6 h,可获得微黄色酸值为24.0～27.0 mg KOH/g的氧化聚乙烯蜡;采用马来酸酐接枝法最佳条件:反应温度155 ℃、反应时间5 h、引发剂加入量2.0%、MAH加入量5%,可获得酸值为48.30 mg KOH/g的接枝聚乙烯蜡.挤出接枝法采用自动化连续生产方法,在挤出温度80～90 ℃,转速30 r/min,扭矩0～4 N · m,引发剂和MAH加入量分别为2.0%和15%条件下,可得到酸值为17.6 mg KOH/g的接枝产品.
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