Diblock polymer-particle composites

Once such distribution is known, the fiee energy is then calculated by standard statistical thermodynamics. The driving force for diffusion is obtained from the spatial gradient of the first functional derivative of the free energy with respect to the density. Here, we describe briefly the equations for both polymer and particle in the diblock polymer-particle composites [38]. 

Ginzburg, V. V., Qiu, R, and Balazs, A. C. Three-dimensional simulations of diblock co-polymer/particle composites. Polymer, 43,461-6 (2002). 

A hydrogenated polybutadiene-PA6 diblock polymer prepared by anionic polymerization of e-caprolactam onto an isocyanate terminated hydrogenated polybutadiene was studied in LDPE/PA6 blends [223] The block copolymer allowed for a very fine dispersion of PA6 in a 80/20 LDPE/PA6 blend with up to an order of magnitude reduction in particle size. Improvement in mechanical properties at both 80/20 and 20/80 LDPE/PA6 blend composition was also observed with the block copolymer addition. 

Fig. 13.6 Sketches of three diblocks of PS/PB having morphologies of isolated nano-spheres of PB in PS, tortuous nano-rods of PB in PS, and parallel platelets of PB and PS, forming composite compliant particles, depicted below, usable for toughening of glassy polymers that can undergo crazing (from Argon et al. (1985) courtesy of The Plastics and Rubber Institute).

Recently, there have been a nirmber of reviews on polymer nanocomposites within this relatively broad topic, there is one specific area that has not, however, been extensively examined namely, mixtures involving nanoscopic rods and polymers. Here, we focus on nanorod polymer composites, where nanoscale rod-like particles are blended with homopolymers, polymer blends, or diblock copolymers. The spatial organization of nanorods within a polymeric material can have a dramatic effect on the composites maaoscopic properties. By elucidating these stracture-property correlations, researchers can pave the way to manipulating morphologies to aeate materials with superior performance and develop... 

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