Polycarbonate characteristic ratio

The helical parameters corresponding to the various skeletal conformations of the blsphenol A polycarbonate chain are calculated. Combining these results with the conformational energy calculations shows that flat-helical and extended conformations are of equal energy for this chain. In addition, cyclic structures are also found to be stereochemically possible. The small values of the characteristic ratio of the unperturbed end-to-end distance and its temperature coefficient are attributed to the equal energy of the flat-helical and extended-helical, as well as the nonhelical, conformers. 

A comparison of the conformational freedom of rotation of the contiguous phenyl groups in polycarbonates, with various substituents at the Ca atom, is presented. Conformational maps are calculated for the polymer shown above. Synchronous rotation of the phenyls with a low-energy barrier is possible for 1, 4, 5, and 8. Although the extent of freedom of rotation depends on the nature of the substituent, there is very little difference in the characteristic ratio of the unperturbed end-to-end distance for these polycarbonates, and the temperature coefficient of the characteristic ratio is extremely small. In spite of the limited conformational freedom, it is shown that the steric symmetry and the geometric asymmetry of the chain segments enable the treatment of these chains in the framework of the freely rotating chain. 

In order to investigate the referenced inkjet-printed film in an OLED, some inkjetted PEDOT-PSS films were used as the anode. On top of the inkjet-printed anode, the hole transport layer (HTL) solution (TPD, [M, M, -bis(3-methylphenyl)-N JV dimethyl benzidine] 67.6 wt.%, polycarbonate (PC) 29.0 wt.%, rubrene 3.4 wt.%, 10.35 mg/ml chloroform) was spin-coated at 1000 rpm for 1 min in a class 100 cleanroom. A 60 nm layer of tris-(8-hydroxyquinoline)-aluminum (Alq3) was then thermally deposited under the high vacuum at the rate of 0.7 A/s. Then, a 300 nm layer of Mg Ag (magnesium -silver) was thermally coevaporated at the ratio of 10 1 on the top of electron transport layer (ETL) layer (Figure 3.10). The thickness of spin-coated layers was matched to one of the inkjet-printed layers (L = 0). Additionally, Figure 3.10 shows results of OLED characteristics with the same layer configuration except that ITO is used as the anode layer. 

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