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Polydimethylsiloxane (PDMS) polymers are highly appreciated materials that are broadly applied in several industries, from baby bottle nipples to rockets. Momentive researchers are continuously working to understand and expand the scope of PDMS-based materials. Fluorofunctional PDMS has helped the world to apply in specialty applications. Efforts are taken to develop such siloxane–fluoropolymer composite materials with good thermal, solvent, and chemical resistance performances. We leveraged inherently flexible PDMS as the model matrix, whereas polytetrafluoroethylene (PTFE) was used as the additive to impart the functional benefits, offering great value in comparison to the individual polymers. The composites were made at three different mixing temperatures, that is, 0–35 °C, and different loadings of PTFE, that is, 0.5–8% (w/w), were selected as the model condition. A strong dependency of the mixing temperature against the performance attributes of the developed composites was noted. Mechanical and thermal stability of the composites were evaluated along with optical properties. X-ray diffraction demonstrated the change in the crystallite size of the PTFE particles as a function of processing temperature. Compared to the phase II crystallite structure of the PTFE, the fibrils formed in phase IV imparted a better reinforcing capability toward the PDMS matrix. A synergistic balance between higher filler loading and mechanical properties of the composite can be achieved by doping the formulation with short-chain curable PDMS, with 238% increment of tensile strength at 8 wt % PTFE loading when compared to the control sample. The learning was extended to check the applicability of doping such PTFE powder in commercial liquid silicone rubber (LSR). In the window of study, the formulated LSR demonstrated improved mechanical properties with additional functional benefits like resistance toward engine oil and other chemical solvents.

A novel, rigid, solution processable, blue‐emitting chromophore based on an extended core of truxene (ExT) was designed and synthesized. The core, ExT based on a fused cyclic trimer of indenofluorene, was found to be planar in nature and a potential precursor for blue emission. This could be selectively brominated under mild conditions to generate a tribromo derivative which underwent ready Suzuki coupling to generate a trisubstituted pyrene derivative, ExT‐P. This coupling alters the kinetics of the excited state considerably as evident from transient absorption spectroscopy, showing faster singlet state decay and less triplet state formation in the case of the pyrene coupled ExT‐P (∼1.6 ns) compared to ExT (∼17 ns). The ExT‐P shows emission maxima at 441 nm and 442 nm in THF solution and film, respectively, with high PLQY value of 0.97. The negligible bathochromic shift in the solid‐state emission and narrow FWHM suggests practically no aggregation and pure blue emission in the target molecule due to bulky and rigid core.

Highly twisted truxene–phenanthroimidazole conjugates have been designed to obtain blue chromophores. The materials show good quantum yields of up to 0.83 and predominant radiative pathways.