Solvent-free UV-curable polymer materials derived from miscible blends of reactive organic monomeric, oligomeric and low molecular polymeric systems and organic and inorganic fillers such as polytetrafluoroethylene and talc are provided to form polymer-filler composite compositions for use in the fabrication and repair of electronic components and microelectronic assembly processes. The composition contains a preformed thermoplastic or elastomeric polymer/oligomer with reactive end groups, a monofunctional and/or bifunctional acrylate monomer, a multifunctional (more than two reactive groups) acrylated/methacrylated monomer, a photoinitiator and a fluorocarbon polymer powder as an organic filler which is preferably PTFE and an inorganic filler such as talc. A nano-filler may also be used as the inorganic filler alone or in combination with another inorganic filler such as talc. A method is also provided for repairing defects on ceramic substrates using the composition of the invention or other curable polymeric compositions.