A number of new poly(organophosphazenes) have been synthesized which bear 2-butenoxy or (4-(allyloxy)phenyl)phenoxy side groups. Cosubstituent groups included trifluoroethoxy, phenoxy, or (benzyloxy)phenoxy groups. Species with (4-(allyloxy)phenyl)phenoxy units underwent Si−H coupling with linear silanes or siloxanes to extend the side groups and form hybrid phosphazene/organosilicon polymers. A number of these polymers are rubbery elastomers which are readily cross-linked by heat or light. Seven of the mixed-substituent, cross-linked polymers were incorporated into interpenetrating polymer networks (IPN's) with polystyrene, poly(methyl methacrylate), polyacrylonitrile, poly(acrylic acid), and poly(dimethylsiloxane). The phase compatibility characteristics of the IPN's were assessed by DSC, TEM, FT-IR spectroscopy, and 1H and 31P NMR spectroscopy data.

In this study, we investigate small molecular organic light-emitting diodes (SM-OLEDs) consisting of emission layers (EMLs) fabricated using a solution-coating process of selfmetered horizontal dip-(H-dip-) coating. The EML used was composed of a co-mixed small molecular host matrix of hole-transporting 4,4',4''-tris(9-carbazolyl)-triphenylamine (TcTa) and electron-transporting 2,7-Bis (diphenyl phosphoryl)-9,9'-spirobifluorene (SPPO13) doped with blue-, green-, and/or red-emitting phosphorescent iridium complexes. To improve the electroninjecting and hole-blocking properties at the cathode interface and to enhance the film-forming capabilities, an interface-engineering additive of poly(oxyethylene tridecyl ether) (PTE) was mixed with the small molecular EMLs. Using PTE additives was shown to reduce dramatically the formation of film defects such as nano-pinholes in the EMLs, resulting in thin and homogeneous PTE-mixed EMLs with smooth surface morphologies, even when using a single H-dip-coating process. The use of simple H-dip-coated EMLs mixed with PTEs in SM-OLEDs resulted in good device performance, with maximum luminance levels of 29,200 cd m -2 , 115,000 cd m -2 , and 16,400 cd m -2 , with corresponding peak current efficiencies of 18.8 cd A -1 , 31.2 cd A -1 , and 10.0 cd A -1 , for blue, green, and red SM-OLEDs, respectively. Furthermore, we demonstrated the feasibility of fabricating large-area and high-performance solutionprocessable SM-OLEDs using H-dip-coated EMLs doped with PTEs. These results clearly indicate that H-dip-coated small molecular EMLs mixed with PTE can be used to yield simple, bright, and efficient solution-processable SM-OLEDs. Textual abstract:A simple and efficent solution-process to fabricate small molecular organic light-emitting diodes (SM-OLEDs) is proposed. The incidence of film defects in the form of nano-pinholes decreases sharply following the introduction of an interface-engineering additive, resulting in good device performance for full-colour SM-OLEDs.

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This paper shows that if a,, = A + B ( i + j ) + Cij, the solutions of Smoluchowski's coagulation equation (monodisperse case) X1(O) = 1, X z ( O l = X3(O) = . . . = 0,can be expressed as equilibrium distributions conditioned on a deterministically changing (and known) parameter. A partial converse is also given. Because the equilibrium distributions are already known, this effectively solves (1) for the given a,,. If C # 0, then there is a finite critical time t = t, when the moments of the right of (1) cease to converge. We find t, for all the given a,i.

We report on the electrical characteristics of AlGaN/GaN high-electron mobility transistors (HEMTs) with hexagonal boron nitride (h-BN) as a passivation capping layer. The HEMTs with h-BN layers showed an increase in current drainage and 103-times reduction in the gate-leakage current compared with those of conventional unpassivated HEMTs. Moreover, the extrinsic transconductance and the pulse responses were improved due to the reduced charge-trapping effect at the surface of HEMTs. From our observations, the h-BN can be used as a passivation capping layer for high-power electronic devices.