Solvents and solvent blends for the polymers TQ1 and N2200.

Sammanfattning: Abstract The solubility of polymers depends on how well the parameters of the polymers and solvents used resemble each other. The more similar the parameters are, the more likely the polymers are to be dissolved. Hansen´s solubility parameters (HSP) tells us how dispersion forces, polar forces and hydrogen bonding influences the structure of the polymers and thereby their solubility. To be able to manufacture effective organic polymer solar cells in the future, we need more knowledge of how polymers and organic solvents interact with each other. This is an essay on how you could gather more knowledge of how primarily the polymer Poly{[N,N′-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5′-(2,2′-bithiophene)} , (N2200), but also the polymer Poly[2,3-bis-(3-octyloxyphenyl) quinoxaline-5,8-diyl-alt-thiophene-2,5-diyl], (TQ1) dissolves in different organic solvent blends. It is also a test on using the computer software Hansen´s Solubility Parameters in Practice (HSPiP), to estimate the HSP:s for the polymers and the polymer blend. The HSPiP was good at estimating the Hansen solubility parameters for the solubility test on N2200. The software´s drawing tool in the do it yourself- part (DIY) that is used to create a structure code-string (SMILES) for the polymer, did not work as well in this project. The Optimizer in HSPiP made good suggestions of organic solvent blends for N2200 and TQ1, that dissolved the polymers. o-Xylene and tetrahydronaphthalene were the solvents that dissolved N2200 in the solubility test in 24 h and 50 ֯C and among the organic solvent blends it was toluene/1-methylnaphthalene, tetrahydronaphthalene/methyl acetate, tetrahydronaphthalene/o-Xylene and tetrahydronaphthalene/2-methyltetrahydrofuran that were able to dissolve the polymers in the concentrations of 10.0 mg/ml. N2200 dissolved very well up to 10.0 mg/ml in the calculated solvent blends but on the other hand, the samples became very viscous at that concentration and hardly fluent, if fluent at all. It was more difficult to find organic solvent blends that could dissolve N2200 than it was for TQ1. TQ1 dissolved in all solvent ratios that dissolved N2200.