Critical inter-particle distance

Arostegui A and Nazabal J (2003) Critical inter-particle distance dependence and super-toughness in poly(butylene terephthalate)/grafted poly(ethylene-octene) copolymer blends by means of poly-arylate addition. Polymer 44 5227-5237. 

Wu [175-177] proposed that the MLT, i.e., surface-to-surface inter-particle distance is a fundamental parameter. For effective toughening, mean matrix ligament thickness (x) should be less than that of the critical value (xj where brittle-tough transition occurs. The x is independent of rubber volume fraction, particle size and characteristics of the matrix alone at a given test temperature and rate of deformation. For blends with dispersed spherical particles, the x can be related to the rubber particle size and rubber volume fraction < >) by the following equation [177] ... 

It has been well recognized from the various studies, as indieated above, that for effective toughening, the concentration of rubber should be above a critical level, which in turn depends on the rubber particle size. Combining these two independent parameters into a single parameter, Wu proposed the concept of critical surface-to-surface inter-particle distance (r), also termed as the critical matrix ligament thickness , as the single key... 

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