Maleic anhydride polypropylene MAPP

Figure 6.3 Structures of maleic anhydride polypropylene (MAPP) (a) and polymethylene polyphenylene isocyanate (PMPPIC) (b).

Joung MP, Son TQ, Byung SH, Lawrence KD (2006) Interfacial evaluation of modified jute and hemp fibers olypropylene (PP)-maleic anhydride polypropylene copolymers (PP-MAPP) composites using micromechanical technique and nondestructive acoustic emissitm. Cranpos Sci Technol 66 2686-2699... 

MA-g-PP Maleic Anhydride-Grafting Polypropylene MAPP Maleic Anhydride Polypropylene... 

TABLE 10.10 The linear coefficient of thermal expansion-contraction for HDPE-based WPC. The published article [4] did not provide details on the formulation of the composite material. MAPP — maleic anhydride derivative of polypropylene (see Chapter 5). 

The wood flour pjartides of 425 microns (40-mesh) in size were kindly donated by American Wood fibers (Schofield, WI) and are constituted predominantly with p>onderosa pine, maple, oak, spruce, southern yellow pine, cedar. The wood was oven dried at 100°C for 24 h before processing to remove moisture. The isotactic polypropylene matrix (PP) has a density of 0.9 g/cm and a melt flow index of 2.5 g/10 min, it was provided by Solvay Co. Polypropylene grafted with maleic anhydride (MAPP) with an approximate maleic anhydride (MA) content of 3 wt. % was purchased from Aldrich Chemical Company, Inc. (Milwaukee, WI). All ingredients were used as received. 

The treatment of cellulose fibers with hot polypropylene-maleic anhydride (MAPP) copolymers provides covalent bonds across the interface (Han et al. 1991). There are two ways of obtaining biocomposites from namral fibers and polymer. In the first one, pretreated fibers with maleated polymer are reinforced with desired polymer matrix. 

The PP molecular weight and amount of MAPP-grafted polypropylene has been considered an important factor influencing the adhesion. Longer PP macromolecules and smaller amounts of maleic anhydride may result in crystal defects. On the other hand, Imiger molecules make the physical interaction between TCL as well as spheruUtes and fiber surface easier [11]. 

Interesting results were reported by Mi et al. [19]. They analyzed polypropylene filled with bamboo fibers with the addition of polypropylene grafted with maleic anhydride. The use of the agent promoting the adhesion was aimed at improving interactions between the components. In case of systems polypropylene/bamboo fibers/compatibilizer, the TCL has been formed. This was explained by higher ability to nucleation of bamboo fibers in relation to MAPP-grafted polypropylene as compared to pure polymeric matrix. 

The effect of flax fiber modification and the effect on the presence of TCL were also studied by Arbelaiz et al. [17]. In his studies, fibers were subjected to maleic anhydride, vinyltrimetoxy silane, and aUcali with addition of MAPP-grafted polypropylene. All applied modifications produced improvement in the thermal stability of lignocellulosic material. Analysis of the crystalline structure showed the increase of crystallinity as a result of fiUer addition. Nucleation density around unmodified fibers was higher than around fibers modified with maleic anhydride. Surfaces of unmodified fibers had the surface active for initialization of transcrystaUization, which, in the case of modified fibers, did not occur. Son et al. [32] explained this phenomenon as... 

Simultaneous influence of polypropylene-graft-maleic anhydride (MAPP) and silane-treated hemp fibers (HF) on morphology, thermal and mechanical properties of high-flow polypropylene (PP) modified with poly[styrene-b-(ethylene-co-butylene)-b-styrene] (SEBS) was studied. Thermal stability of HF was improved... 

In a study of the properties of composites containing wood cellulose and thermoplastics, it was found that the strength and stiffness of these materials were significantly improved by the use of maleic anhydride-modified polypropylene (MAPP). ITie nature of adhesion was studied with FTIR, ESCA and SEM. The chemical bonding between MAPP and cellulose surfaces was proven to be responsible for promoting interfacial adhesion. 

The aim of this research was to create novel composites for bulk applications using cellulose as reinforcement. We intented to improve properties of polymer composites reinforced with cellulose by pretreating fibers with maleic anhydride modified polypropylene (MAPP). The effect of hydrolytical treatment of cellulose on the dispersibility of fibers in polymers was also investigated. Novel materials based on bacteria-produced polyesters and cellulose were manufactured and their properties evaluated. 

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