Coupling agents maleic anhydride-grafted

Some authors combined the IPN concept with the use of compatibi-lizers similar to that mentioned in Section 2. These may be a coupling agent such as epoxy-functionalized polysiloxane, polysiloxane copolymers or an organofunctional grafted polyolefin such as poly(ethylene-co-methacrylate) or MA-g-EPDM (maleic anhydride grafted EPDM) [124,125, 133]. Knaub et al. [150] studied a poly(urethane-ureas)/PDMS semi-IPN in... 

Several types of maleic anhydride-grafted Epolene coupling agents are manufactured—PE-based Epolene G-2608 and PP-based Epolene E-43, G-3002, G-3003, and G-3015 (manufactured by Eastman Chemical Products). Some of their properties are shown in Table 5.4. 

Best results in WPCs usually require a strong coupling of wood fibers to the matrix (discussed more in Chapter 14), using maleic-anhydride-grafted resins or other coupling agents. 

Yazdaiu, H., Morshedian, J., and Khonakdai H.A. (2006) Effects of silane coupling agent and maleic anhydride-grafted PP on the morphology and viscoelastic properties of PP-mica composites. Polym. Compos., 27, 491-496. 

Patty acid (stearic, isostearic) and other polar coupling agent effects on rheology and properties of CaC03 filled polyolefins are discussed in detail in Chapter 6. The beneficial effects of maleated PP in filled PP compounds are shovm in Table 6.9. Modification of the polyolefin matrix of Table 16.2 by maleic anhydride grafting through reactive extrusion increases the tensile and fiexural and unnotched impact... 

Natural materials that have been used to modify polymer properties include wood sawdust [188, 189], coconut fiber [167], carbon fibers [37], oat husks, cocoa, shells [190], sugarcane fibers [191], and banana fiber [193]. Monhonty and coworkers [193] observed a 70% increase in the flexural strength of polypropylene to which has been added 30% jute with a maleic anhydride-grafted polypropylene coupling agent. 

Figure 2.2 A schematic diagram of the reaction of the silane coupling agent (KH550) with maleic anhydride grafted polypropylene and an inorganic substance on the surface.

The most recent significant development in the market place has been the very strong growth in the use of cellulose fiber reinforced composites, especially those based on wood fiber and powder. Coupling agents are often used in these formulations, especially to reduce water absorption and accompanying loss of properties. Maleic anhydride grafted polyolefins have been found to be very suitable additives for this purpose, and this has led to a marked increase in their use. 

Matrix modification based on MA-g-PP, affects the interfacial adhesion and mechanical properties of jute/PP composites. The effect of maleic anhydride-grafted-PP (MA-g-PP) coupling agents on the properties of jute fiber/PP composites has been studied. The addition of 2 wt% MAPP to PP matrices can significantly improve the adhesion strength with jute fibers and in turn the mechanical properties of the composites. 

In addition, ABS that has been recovered can be recycled into high value composites without separation from impurities. This has been exemplified with wood-plastic composites that contain ABS as matrix polymer. Both virgin ABS and recycled ABS were used and the properties of the materials were compared (126). In order to increase the performance, coupling agents were used, all based on grafted maleic anhydride. 

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] ... 

Wood flour from maple, 120 mesh, vacuum dried. The coupling agent was maleated polyethylene containing 1% (w/w) grafted maleic anhydride (Epolene G-2608, Eastman Chemicals). The lubricant was alkene bis fatty amid (Glycolube WP-2002, Lonza Inc.) [4]. 

On further examination, over half of the AST patents listed were classified as associative in this review. Although most of these occur in more recent years, the earliest found (59) happens to be the first entry in the tables. In this and four other former issues (62, 64, 69, 70) that differ in the type of hydrophobic monomer employed, a maleic-anhydride-con-taining prepolymer is prepared and subsequently post-esterified with a nonionic surfactant. In essence, the associative side chains are grafted onto the polymer backbone. In nearly all of the other associative patents, the associative monomers are synthesized first and then copolymerized with the carboxylic acid and hydrophobic monomers. Many similarities also exist between the various associative AST patents. In refs. 62, 64, 69, and 70, the hydrophobic monomer was an obvious variable. In some others, differentiation is a manifestation of the type of coupling agent used. 

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