Polypropylene with maleic anhydride

There are several reports on the influence of fillers on shrinkage. " Figure 8.56 shows mold shrinkage vs. concentration of filler. Mold shrinkage can be reduced to half of the value for unfilled resin by the incorporation of mica. Additional reduction of shrinkage is possible if the interaction between filler and the matrix can be increased. This can be achieved by reacting polypropylene with maleic anhydride. ... 

The most commonly used compatibilLzers for the blends are graft copolymers of polypropylene with maleic anhydride (PP-g-MAH) (197-203), glycidyl methacrylate (PP-g-GMA) (204,205), and acrylic acid (PP-g-AA) (198,206). They can increase the tensile strength and impact strength of the blends. Favis et al. (207-210) used an ionomer, a copolymer of ethylene and a mixture of methacrylic acid, zinc methacrylate, and isobutylacrylate to compatibUize PP/PA blends and found it effective to decrease the dispersed particles and improve mechanical properties. 

Functionalization of isotactic polypropylene with maleic anhydride by reactive extrusion mechanism of melt grafting. Polymer, Vol. 42, pp. 5549-5557, ISSN 0032-3861. 

A. R. Oromehie, S.A. Hashemi, D. N. Waters, Functionalisation of Polypropylene with Maleic Anhydride and Acrylic Acid for Compatibilising Blends of Polyproylene with Poly(ethylene ter-ephthalate). Polymer International 42 (1997) 117. 

Minoura, Y., Ueda, M., Mizunuma, S., and Oba, M. 1969. The reaction of polypropylene with maleic anhydride. Journal of Applied Polymer Science 13 1625-1640. 

Another method developed by Hercules Inc. (9) consisted of reacting crystalline polypropylene with maleic anhydride in the presence of organic peroxide in an inert liquid organic solvent. This process is expensive because it requires the separation of solvent and excess maleic anhydride from the modified polypropylene. A similar process, detailed in patent 3,414,551, uses a fluidized bed of polymer particles instead of a solvent. 

A Hogt. Modification of Polypropylene with Maleic Anhydride. ANTEC, 1988, pp. 1478-1480. 

Poly[imino(l-oxohexamethylene)] Nylon 6 70/30 blend with 10% polypropylene with maleic anhydride... 

A 3000 molecular weight polypropylene ether) triol (Arcol F3020, 90 g) was mixed with maleic anhydride (60 g) and zinc chloride (2.25 g) in a three-necked round-bottomed flask equipped with a magnetic stirrer, a condensor and a thermometer. Under a nitrogen atmosphere, the reaction mixture was heated to 190 °C... 

Interchain copolymer formation Copolymers of reactive polystyrene and polymers with amide, mercaptan, epoxy, hydroxy, anhydride or carboxylic acid groups, copolymer of polypropylene grafted with maleic anhydride and nylon-6, copolymer of polyolefines and polystyrene, copolymer of EVA grafted with methacrylates and grafted polystyrene... 

A reactor was charged with polypropylene containing an ene terminus (250 g), and the temperature was increased and maintained at 185°C. This material was then treated with maleic anhydride (20 g) dissolved in 24 ml of acetone followed by the dropwise addition of di-t-butyl peroxide (6 g). The reaction was maintained at this temperamre for 3 hours and then gradually cooled over 60 minutes. The product was isolated having an 11.3% maleic anhydride content. 

The second system was based on two semi-crystalline polymers polypropylene and polyamide. To attain potential reactivity, polypropylene was first grafted with maleic anhydride and the results of this radicalar melt-grafting are presented. The final blend was obtained in one-step extruding of the two homopolymers and the reactive polypropylene. 

PP- g AM Polypropylene grafted with maleic anhydride PP-g AM/ST PP grafted with maleic anhydride and styrene... 

Polar polypropylene waxes are produced by grafting of PP with maleic anhydride. 

The same technique can be used to dye a material that is otherwise difficult to dye. An ethylene-propylene copolymer rubber was reacted first with maleic anhydride, then with an aromatic amine dye in an extruder to produce a dyed rubber.81 Dye sites can also be inserted into polyolefins by grafting them with dimethylaminoethyl methacrylate, using azo or peroxide catalysts in an extruder.82 jV-Vinylimidazole has been grafted to polyethylene in an extruder with the help of dicumylperoxide.83 The product was mixed with an acrylic acid-modified polypropylene and used to compatibilize polyethylene and polypropylene. This could be helpful in the recycling of mixed polyolefins from municipal solid waste. Recycling of cross-linked (thermoset) polymers is more of a problem because they cannot be remelted in an extruder. However, they can be if... 

TABLE 4.29 The same as in Table 4.28, but in the presence of 4% of a coupling agent, polypropylene grafted with maleic anhydride [24] ... 

Eor polypropylene/polyamide/grafted rubber ternary blends, TEM was proved to be a good tool to study their phase morphology. Without grafting, EPR (217) or SEBS (218) formed dispersed particles together with the minor component of the blends separately however, after grafting with maleic anhydride they could encapsulate the dispersed minor component of the blends (214,217-221). 

After preliminary studies conducted on isotactic polypropylene and maleic anhydride in the presence of dicumyl peroxide as initiator, we concluded, in agreement with several others, the existence of a maximum grafting level, or ceiling, whatever was the initial concentration of maleic anhydride and peroxide in the reaction media. By using a statistical design method for experimental runs, it was put into evidence that results needed to be carefully evaluated in order to find the true evolution of the process. 

The polypropylene was obtained from Liaoyang Petrochemical Corp., P. R. China (ref. 401), and the polyamide 6 (PA6) from Shanghai Plastics Production Factory No. 18, China. The polyethylene-octene (POE) modifier, obtained from Dow Chemical Co (octene content of 9.5% and melt flow index of 3.5 g/10 min), was grafted in the laboratory with maleic anhydride at a ratio of about 1 % in weight. 

Porous acrylonitrile—DVB copolymer further reacted with diamines or triamines provides a support for Cp 2ZrCl2—MAO catalysts.2 2 pjjg catalyst activity rivals that of silica-supported analogues and no adhesion of polymer to the reactor walls or stirrer was observed. Polypropylene grafted with maleic anhydride allowed to react with MAO acts as a support for a variety of metallocenes. 3 The number of gels in the polymer is lower than when silica is used as the carrier. Porous vinylpyridine—DVB and poly(vinyl chloride) have also been reported as suitable support materials for metallocene catalysts. 

---