Maleic anhydride terminated polyolefins

Some preformed compatibilizers, such as Kraton [93] and Vector [94], are commercially available and ready for use. Priex [95] maleic anhydride terminated polyolefins (PP-MA and PE-MA) are commonly used to compatibilize minor levels of contamination in PE and PP streams. Other postformed compatibilizers require a reaction or chemical or physical change during the mixing or processing step before they show efficacy. Materials used as postformed compatibilizers are generally not compatibilizers themselves but, because of an in sim reaction, result in compatibilization. 

Coran and Patel [74] investigated the reactive com-patibilization of PP-NBR and HDPE-NBR blends using phenolic modified polyolefin, maleic anhydride modified polyolefin, and amine terminated nitrile rubber as reactive components. Dynamic vulcanization was also inves-... 

The third advantage associated with metallocene catalysts is that the predominant mechanism for chain termination is by /3-hydride elimination. This produces a vinyl double bond at the end of each polymer chain. Further functionalization of the vinyl group by graft polymerization with maleic anhydride and other functional monomers is far more effective than is typical for polyolefins obtained by conventional catalysts. 

We have previously reported a practical and cost-effective method to obtain PDMS-polyolefin compounds by reactive melt mixing of an ethylene-ethyl acrylate-maleic anhydride (EEAMA) copolymer and aminopropyl terminated PDMS. In this study, the PDMS-modified polyolefin (PMPO) is used as a processing aid for the extrusion of a LLDPE. Improvements in extrudate surface quality and shear stress reduction after adding 5 wt% of PMPO with different levels of PDMS content are presented and related to changes in the surface free energy of the PMPO. The friction coefficients of PMPO and its compounds with LLDPE were measured in an effort to provide experimental support of the observed behavior. 

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