Grafting composition

It is a well-known fact that the mechanical properties of fluoropolymers, especially perfluoropolymers, degrade dramatically under irradiation. Nevertheless a considerable improvement of the mechanical properties of the final grafted copolymers was observed in comparison with mechanical properties of the initial irradiated fluoropolymer. Thus it is possible to minimize or completely avoid the degradation of mechanical properties of the final grafted composites in comparison with the initial fluoropolymers by choosing appropriate reaction conditions. 

Mechanical Properties. The properties of a composition containing 5% of EPR are shown in Table V. The tensile properties and the shear modulus of this composition are slightly lower than those of a rigid PVC of the same K value. Shore hardness and deflection temperature are comparable in the two cases. In comparison with rigid PVC, the grafted compositions have an excellent impact strength that increases with the molecular weight. 

Since about half of the epoxy resin and about two-thirds of the acrylic are free, the grafted composition is now listed in Table (III). 

Starting Composition m mole Graft Composition m mole Ratio... 

Ulbricht, M. and Schwarz, H.H. 1997. Novel high performance photo-graft composite membranes for separation of organic hquids by pervaporation. 136 25-33. 

First grafting Second grafting Composition (% Graft) Flux (gfd-mil) Salt g rejection (7o) i 0 5 1- ... 

K. R. Sharma, Graft Composition Stability in Continuous Mass Copolymerization, Middle Atlantic Regional Meeting of ACS, MARM 02, Fairfax, VA, May 2002. 

The results of normalized strength and modulus as a function of monomer content (%) in compatibilized composites are shown in Figure 7. The strength first increased in pre-grafted LLDPE composite due to the improvement at the interface of the matrix and bamboo-fiber and then showed no trend with the addition of compatibilizer. It was clear that the p-grafted composites held good strength with the addition of 1.5%... 

K. T. Okamoto, K.D. Eastenson, and S.C. Guyaniyogi, Engineering resin-propylene polymer graft composition, US Patent 5 290 856, assigned to HIMONT Incorporated (Wilmington, DE), March 1,1994. 

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