Polypropylene-graft-maleic anhydride blend compatibilizer

The addition of a polypropylene grafted maleic anhydride (PP-g-MA) compatibilizer into polypropylene-co-ethylene/polybutylene succinate blends and the subsequent irradiation allowed prevention of degradation mechanisms leading to mechanical stability. The cyclic anhydride group of the PP-g-MA first permitted compatibilizion of both polypropylene-co-ethylene and polybutylene succinate and a second action as an "energy sink."... 

Els and McGill [48] reported the action of maleic anhydride on polypropylene-polyisoprene blends. A graft copolymer was found in situ through the modifier, which later enhanced the overall performance of the blend. Scott and Macosko [49] studied the reactive and nonreactive compatibilization of nylon-ethylene-propylene rubber blends. The nonreactive polyamide-ethylene propylene blends showed poor interfacial adhesion between the phases. The reactive polyamide-ethylene propylene-maleic anhydride modified blends showed excellent adhesion and much smaller dispersed phase domain size. 

One of the earliest references on compatibilizing a nylon-6-polypropylene blend using maleic anhydride grafted PP (PP-g-MAH) was the work of Ide and Hase-gawa published in 1974 [35]. In their study, the formation of a graft copolymer was confirmed by DSC after solvent extraction of the PP component. Blends with PP-g-MAH... 

Y.-Y. Cui, B.-J. Dong, B.-L. Li, S.-C. Li, Properties of polypropylene/poly(ethylene terephthalate) thermostimulative shape memory blends reactively compatibilized by maleic anhydride grafted polyethylene-octene elastomer. Int. J. Polym. Mater. Polym. Biomater. 62, 671-677 (2013)... 

In order to be able to modify and control the interfadal interactions in the above-described manner, it is extremely important to monitor the structure of the interfadal layer. Ellipsometry was used [15,40,50,51] to deted the procedure and influence of reactive compatibilization on polymer blends. In an early study, the reactive blending of polypropylene (PP) with amorphous polyamide (aPA) was carried out using maleic anhydride-grafted PP (MAH-gPP) as a reactive PP [50]. The emulsifying effect of the in situ-formed PP-aPA graft copolymer was indicated by finer particles and a better stability of the dispersed phase obtained in bulk. In accordance with these findings, ellipsometry showed that the interface established in the reactive system was rather thick (ca. 40 nm), indicating an improved compatibility. 

Compatibilizers are frequently materials such as block or graft copolymers. A specific example would be a copolymer comprising two blocks where each is compatible with one component of the blend (in a blend of two plastics) and incompatible with the other. An A-x-B block copolymer, where A and B are long sequences of monomer that are identical to the corresponding A and B polymers forming the blend, and X is a bond between the blocks, is one of the simplest forms of compatibilizer. A functionalized polymer where the main polymer is compatible in one phase and the functionality is compatible in the other phase would be another example of a compatibilizing agent. One example of such a material would be maleic anhydride functionalized polypropylene (PP-MA) used to compatibilize blends of PP and Nylon 66. Recent advances in the production of PP-MA have seen an increase in the impact resistance of... 

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