This article mainly concerns the synthesis of novel PD5/PDMS conetworks by the copolymerization of cyclic D,H and linear HO-PDMS-OH units, and the characterization of the product by DMTA, DSC, and TGA. The ultimate properties of the conetworks may be controlled by varying the relative composition of D5H and PDMS components. DMTA and DSC thermograms indicate compatibility between the PD5 and PDMS domains. Understanding of the polymer chemical transformations involved in conetwork formation combined with an analysis of DMTA and DSC thermograms led to a proposition of the microarchitecture of PD5/PDMS conetworks. (C) 2004 Wiley Periodicals, Inc.