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We study experimentally the influence of mass fraction of L-20 hardener cold cure on mechanical properties of epoxy diane resin ED-20. We measure the hardness, tensile strength, bending strength and impact strength of resin at different values of the hardener mass fraction. It is found that the ratio hardener mass fraction of 1:0.9 leads to the highest values of the hardness, tensile strength, compressive strength and bending strength. The impact viscosity is maximum at the ratio hardener mass fraction of 1:0.8. The optimal ratio of a non-toxic safe hardener to the resin is derived based on obtained mechanical characteristics.

We present one of the central and basic factors related to the TiO₂ photoanodes of optimal absorption site. Binder is of particular importance for surfaces and interfaces that involve organic dye and TiO₂ layer. We introduced monodispersed liquid copolymer binders; poly(ethylene glycol)-ethyl ether methacrylate (PEG-EEM) instead of solid PEG to increase TiO₂ electrode's surface area. We attempt to investigate the morphology of the photoanodes and photovoltaic effects using field emission scanning electron microscopy (FE-SEM), BET and photovoltaic properties under illumination with AM 1.5 simulated sunlight. We achieve 167% enhanced power conversion efficiency when the optimal content of liquid PEG-EEM binder was 4 wt.% than that of PEG binder. We show that the performance of Dye-sensitized solar cell (DSSC) can be strongly improved using liquid type binder.

In performing process of liquid composite molding, the binder can enhance the near net shape of the fabrics, while the viscoelastic model which can predict the recovery behaviors for the fabrics with binder has not been reported yet. Here, a viscoelastic model, which consists of parallel dashpot and spring elements, is originally developed to predict the recovery behaviors. Systematical experiments of typical carbon fiber fabrics were conducted to validate the proposed model. The viscoelastic theoretical curves match well with the experimental measurements, demonstrating the model can well capture the strain evolution in the recovery process. Besides, with the added binder, the minimum strain and recovery stain limit respectively significantly increased and reduced, confirming the addition of binder can remarkably reduce the recovery deformation, and promote the near net shape of fabrics. Besides, the delay time, which characterizes the time required for the completion of recovery process, enlarges with the increased contents of binder, and this result is consistent with the theoretical prediction. Correspondingly, the time for maintaining the net shape of the fabrics in performing process can be increased by using binder, which will be favorable to practical preforming process.

To determine the optimal dispersion conditions of graphene flakes for ink, its heat dissipation properties were investigated by changing the particle size, dispersant, and binder types. In the case of particle size, the smaller the size of the graphene flakes, the better the dispersion, and regardless of the amount of dispersant and the type of binder, the greatest dispersion effect was exhibited by the mixed dispersant. Under these conditions, internal cohesion did not occur as in Newtonian flow over time, and for this reason, heat was released quickly, with a rapid cooling rate. It is clear that this process of determining the optimal dispersion conditions considering multiple factors will provide a good reference for determining dispersion conditions for various variables in the future.