Graft copolymer alloys, impact strength

Figure 17. Notched Izod impact strength of PVC-VC/PE graft copolymer alloys and proportion of unbroken specimens hammer 10 ft-lb...

Figure 18. Influence of the gelling time on the Izod impact strength (notched) of a PVC/PE graft copolymer alloy (87% Solvic 239 + 13% VC/LD PE (50-50) graft copolymer) hammers 3 ft-lb, 10 ft-lb...

VC/Polyepichlorohydrin and VC/Poly(epichlorohydrin-co-ethylene oxide) Graft Copolymers. Alloys of PVC and graft copolymers of this type with high backbone-polymer content give interesting results in the field of bottle blowing (12). The combination of transparency and impact strength that can be realized with these compositions should enable them to penetrate into the field covered at present by PVC-MBS mixtures. 

Dow has prepared a compatibilized blend of PC and linear PE. The compati-bilizer used was EPDM grafted with SAN. The product has high impact strength and good melt processability. Polymer alloys with S-AMS copolymer and PP with styrene-grafted polyolefin copolymer have been reported. Triax 1000 of Monsanto is a blend of nylon and ABS compatibilized with styrene-acrylonitrile and glycidyl methacrylate terpolymer. The compatibilizer often improves the property balance of an immiscible blend. Reactive compatibilization is an emerging technique. 

Various approaches have been undertaken for reactive compatibilization of poly-amide/ABS alloys. Maleic anhydride can be grafted to the ABS. Styrene maleic anhydride (SMA) copolymers have been employed as compatibilizers for polyamide/ABS blends. SMA and SAN copolymers are miscible when the AN and maleic anhydride (MA) contents are equal. The impact strength of these blends has been found to be sensitive to the amount and composition of the SMA copolymer. Addition of SMA to SAN/polyamide blends was found to enhance the tensile and impact properties of these blends. Imidized acrylic polymers have been used as compatibilizers for nylon-6/ABS blends. Glycidyl methacrylate and methyl methacrylate (GMA/MMA) copolymers are used as compatibilizing agents. The epoxide functionality in GMA is capable of reaction with polyamide end groups. GMA/MMA copolymers can be shown to be miscible with SAN over the range of AN content of ABS. Styrene/GMA copolymers have been reported to be used as compatibilizers for polymer pairs such as... 

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