Interrelationship between microstructure and application properties

HIPS microstructure depends on the process variables used in the polymerization. There are many publications reporting experimental evidence of the effect of the process variables on polymer microstructure [7-16], For example, Soto et al. [15] analyzed the effects of the initiator type, temperature and stirring rate on the particle morphology and molecular weights of the free PS. Heuristic knowledge available indicates that the particle size depends on the ratio between the solution viscosities of the PBD- and PS-rich phases the agitation rate and the interface tension between the two phases. The interface tension in turn depends on the grafting efficiency. 

F rticle size First increase, then decrease No effect Slight increase Decrease Decrease Increase 

Mw of free PS First rapid increase, then no effect Slight increase Slight increase Decrease Increase Decrease 

Mineral oil Increase Decrease Decrease No effect Decrease Increase 

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