Heterogeneous Materials Based on Polypropylene

Jesus Maria Garcia Martmez Susana Areso Capdep6n Jesus Taranco Gonzalez and Emilia Perez Collar  

Since the begitming, organic polymers have been combined with another substances, mainly inorganic, to lower costs. However, the reinforcement effect in the polymer-based material caused by the presence of a second component was soon ascertained (1). 

Polyolefin Blends, Edited by Domasius Nwabunma and Thein Kyu Copyright 2008 John Wiley Sons, Inc. 

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INTERFACIAL MODIFICATION OF HETEROGENEOUS MATERIALS BASED ON POLYPROPYLENE... 

When building a model to predict the mechanical behavior of heterogeneous materials based on polypropylene, the basic principle of fracture mechanics should be considered that fracture is induced in a material when an energy threshold on the weakest zones is reached. It is also well accepted that such energy threshold consists of at least two components necessary energy to initiate a craze and the necessary energy to propagate it. 

Environmental considerations and sustainable development criteria when applied to the materials design field should favor the applications based on the organic thermoplastic polymers (64). The high versatility of polypropylene has placed it beyond the border of commodities to become an engineering polymer. Indeed, new developments based on this polyolefin would be the key in the strategic area of the heterogeneous materials based on organic polymers, both from an academic as well as technical point of view. 

In the early 1950s, Ziegler observed that certain heterogeneous catalysts based on transition metals polymerized ethylene to a linear, high density material at modest pressures and temperatures. Natta showed that these catalysts also could produce highly stereospecific poly-a-olefins, notably isotactic polypropylene, and polydienes. They shared the 1963 Nobel Prize in chemistry for their work. 

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