Maleic anhydride, grafting reactions onto

The reactive extrusion process for grafting maleic anhydride monomer (MAH) onto polypropylene backbone involves a balance of simultaneous reaction steps as described in Chapter 3 ... 

SAN can be modified, for example by grafting. For example, maleic anhydride (MA) can be grafted onto SAN. This process occurs preferably in a twin-screw extruder by reactive extrusion. An advantage of reactive extrusion is the absence of solvent as the reaction... 

Reactive extrusion takes place when the twin screw system is designed to incorporate one or more chemical reactions during the process, such as grafting or even polymerization. Grafting is the process of attaching pendant molecules onto the backbone of a polymer chain. For example, a small concentration of maleic anhydride can be incorporated into polypropylene to make the... 

Grafting reaction Reaction of a monomer and a polymer to form a grafted polymer or copolymer Grafting vinyl silanes onto polyolefins for crosslinked polyolefins acrylic acids onto polyolefins for hydrophilicity maleic anhydride onto polyolefins for compatabilization... 

Bettini, S.H.R. and AgneUi, J.A.M. 1999. Grafting of maleic anhydride onto polypropylene by reactive processing. I. Effect of maleic anhydride and peroxide concentrations on the reaction. J Appl Polym Sci. 

Mechanism of free radical initiated grafting reaction of maleic anhydride onto PE (from ref 11). 

Propose the reaction mechanism of grafting of maleic anhydride onto the polyethylene. 

The reasons for the use of maleic anhydride instead of other anhydrides or unsaturated carboxylic acids is not clearly stated in Chapter 10. If you possess an extensive knowledge of chemistry, you will know that maleic anyhydride is a cheap, safe, readily reactive compound which puls carbor lic acid sites onto a polymer by formation of a carbon carbon bond. The reaction is specific as long as aliphatic or aromatic groups are the only functional groups in the polymer being grafted. 

Gaylord, N. G. and Mishra, M. K. 1983. Nondegradative reaction of maleic anhydride and molten polypropylene in the presence of peroxides. Journal of Polymer Science Letters 21 23-30. Gaylord, N. G. and Mehta, R. 1988. Peroxide-catalyzed grafting of maleic anhydride onto molten polyethylene in the presence of polar organic compounds. Journal of Polymer Science, Part A Polymer Chemistry 26 1189-1198. 

GRAFTING REACTIONS OF MALEIC ANHYDRIDE ONTO POLYPROPYLENE... 

There have been many studies conducted on the grafting of maleic anhydride onto polypropylene. These studies have produced many different theories on the grafting mechanism. One important aspect to consider in comparing the results from these studies are the methods used to conduct the grafting reactions. Different compounding methods, different initiator types, and monomer and peroxide... 

Figure 3.2 Possible reaction mechanism for grafting maleic anhydride onto polypropylene according to De Roover et al. (From Ref. 15, Reprinted with permission of John Wiley Sons.)...

Figure 3.4 Possible reaction meohanism for grafting maleic anhydride onto...

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