Compatibilized composite

Wang, Y., Chen, F.-B., Li, Y.-C., and Wu, K.-C. 2004. Melt processing of polypropylene/clay nanocomposites modified with maleated polypropylene compatibilizers. Composites Part B 35 111-124. 

Keywords Compatibilization Composites Natural Fiber Polyolefin... 

The compatibilizer can be prepared first and melt blended with the polymer blend or it can be produced in situ during melt mixing of the blend. The compatibilizer composition will depend upon the polymer pair that is being compatibilized. 

The objective of this research is to compare the thermal and tensile properties of —in situ (i-) grafted polymer compatibilized composites with pre (p-) grafted polymer compatibilized composites. In turn, this research gives an idea of advantages and disadvantages of both the process in terms of the manufacturing methods employed to fabricate the composites. 

Melting Behavior and Crystallinty Index of Differently Compatibilized Composites... 

The results of normalized strength and modulus as a function of monomer content (%) in compatibilized composites are shown in Figure 7. The strength first increased in pre-grafted LLDPE composite due to the improvement at the interface of the matrix and bamboo-fiber and then showed no trend with the addition of compatibilizer. It was clear that the p-grafted composites held good strength with the addition of 1.5%... 

Figure 7. Effect of monomer content (MA/GMA) in compatibilized composites on normalised tensile properties.

Figure 9. Flow chart of grafting technique to obtained compatibilized composites.

Lee, J. H., Jung, D., Hong, C. E., Rhee, K. Y, and Advani, S. G. Properties of polyethylenelayered silicate nanocomposites prepared by melt intercalation with a PP-g-MA compatibilizer. Composites Science and Technology, 65, 1996-2002 (2005). 

With up to 40% clay, the compatibilized polymer/clay composites exhibit lower water vapor permeability than typical unfilled polyethylene. The compatibilized composites containing the clay particles were crosslinked, with the anhydride-grafted polyethylene bonded to the clay particles and uncrosslinked polyethylene. The composites exhibited improved flexural modulus, break strength, and notched Izod impact properties. 

R. R. N. Sailaja, and M. V. Deepthi, Mechanical and thermal properties of compatibilized composites of polyethylene and esterified lignin. Materials Design 31 (9), 4369-79 (2010). 

Accordingly Moraviec et al. (2005) also described no increase in the thermal stability of LDPE independently if the nanoclay underwent exfoliation or not. These authors described an improved thermal stability of the compatibilized composites in air. Sanchez-Valdes etal. [18] also found that the exfoliated or intercalated clay inhibited the polymer decomposition in air, which were justified by the improved barrier for diffusion of oxygen into the material and also by the diffusion of the degradation by-products from the sample. 

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