STRUCTURE FACTORS FOR REGULAR POLYMER GELS AND NETWORKS

Structure factors, P(q), for regular dendrimeric polymer gels and two- dimensional tetrafunctional networks are calculated. Since the low-q l imit (q being the scattering wave number) region is uninteresting for these systems (the Guinier region yields gel and network overall sizes ), this paper focuses on the intermediate q region, whereby the scatte ring radiation is probing sizes larger than single blocks but smaller than the whole macromolecule. Kratky plots [q2P(q) vs q2] are presente d for starburst dendrimer gels with varying functionality and correlat ion range r (with respect to a reference block) and for ''crumpled she et'' tetrafunctional networks with varying r. For regular networks, th e structure factor has contributions from the various ''lattice animal s'' that correspond to a chosen pair of correlated blocks. A simple me thod based on multivariate Gaussian distributions is used to express t he mean square intermonomer distance [r(ij)2] for not too complicated correlation diagrams (r < 4).