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Article in two ways by the solution method and the melting method , sodium hydroxide , zinc hydroxide , respectively, and the maleic anhydride-grafted polyethylene (mPE) ionic reaction , synthesis of different ionization degree , and has ion - crosslinked structure the mPE sodium ionomers and mPE zinc ionomers. By FTIR mPE sodium , zinc ionomer structural characterization , analysis of the two ways the different reactions of the process and the sodium and zinc ionomer ionic crosslinking mechanism. Melt flow rate ( MFR ) , DSC , WXRD rotational rheometer , TGA, sag , water absorption and tensile testing of the performance of the mPE ionomer melt crystallization , rheological properties, thermal stability , physical crosslinking , water absorption , mechanical properties and their relationship with the degree of ionization and ion species . The studies show that the in MPE ionomer system , with the added amount of sodium hydroxide or zinc hydroxide improve , ionization degree improve , but can not reach 100% ionization ; With the improvement of the degree of ionization of sodium , mPE , decline in MFR of the zinc ionomer , melt strength increased , and the role of physical crosslinking , but increased brittleness, the mechanical properties decrease . By FTIR analysis , from ion sodium ionomer ionically crosslinked aggregates or the formation of ion clusters , while the zinc from zinc ionomer crosslinking the role of the ligand and the small amount of ion aggregation; so performance stronger than the sodium from the physical cross -linking action of the prepolymer zinc ionomer , sodium ion of mPE various performance than zinc ionized more apparent . Compared with mPE sodium ions after melting temperature Tm is increased by 1 to 6 ° C , the crystallinity Xc decreased by 5 % to 12% , the water absorption increases ; zinc ion after TM increased by only 1 to 2 ° C , the degree of crystallization Xc fell 1.5 ~ 6% , the water absorption is reduced ; the mPE zinc from the size of the ion - enriched microdomains in the prepolymer is greater than the sodium ionomer . Rheological analysis showed that the sodium, zinc and ionized MPE molecular chain activity decreased , and the loss tangent tanδ is less than 1 ; found of mPE and its ionomers in occur degradation of molecular chain crosslinking, the ionomer from more than 230 ℃ beginning degradation the crosslinking temperature than mPE combined TGA analysis showed that after mPE ionized the molecular chains thermal stability is improved . In addition, by analysis of the ionomer anti sag resistance studied the interacting relationship of the ionomer in the ionic crosslinking and the gravity .
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