| In this paper crosslinkable PE is studied by silane crosslinking and peroxide crosslinking . Effects of silane on gel fraction are discussed. And effects of different types silane on crosslinking reaction are compared. Effects of catalyst> antioxdantN evocator on properties of PEX are compared. At the same time the flow behaviour of graft PE is studied by HAAKE rheoriscometer and reaction mechanism of grefting and crosslink are tested and verified. Then the oil resistance^ the strain/stress curve and the microstate are introduced. The kinetics of grafting and crosslinking are studied. The results show that grafting reaction follow first order kinetics with respect to silane concentration, and crosslinking reactions follow first order kinetics with respect to both catalyst and moisture concentration. The manufacturing technology of peroxide crosslinking PE as well as effects of raw materials and their amount on the compound properties are introduced. And the electric behaviour and ageing property of peroxide crosslinking PE are studied. Lastly, the commercial process of silane crosslinking PE is studied. The suitable process and formula are found. PEX has been mass-produced for many factories. The pipe made by the PEX had been tested by the national testing center of chemical buildingmaterials, every behaviour has come up to American standard ASTM. It can replace the imported PEX.
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