This thesis explores the evaporation kinetics of various polymer-solvent and binary solvent mixtures to explore possible connections between the solutions properties and their evaporation process. By looking at the evaporation of polymer-solutions and binary-solvent solutions, through the change in weight as the solvent evaporates and the evaporation rate of the evaporation process, potential connections could be found. The results indicate that the presence of polymers influence the solvent evaporation, with polystyrene (PS) generally accelerating and polymethyl methacrylate (PMMA) either decelerating or having minimal impact on evaporation rates. Binary solvent mixtures exhibited non-proportional increases in evaporation rates, suggesting complex intermolecular interactions, but no apparent patterns between their properties and deviation in the evaporation process. This would need further research to find possible connections to be able to predict the evaporation process. But these findings highlight the importance of understanding polymer-solvent compatibility and evaporation dynamics to enhance performance and to identify environmentally friendly solvents for organic photovoltaic (OPV) cell fabrication. / Detta examensarbete undersöker avdunstningskinetiken hos olika polymer-lösningsmedel och binära lösningsmedelsblandningar för att utforska möjliga samband mellan lösningarnas egenskaper och deras avdunstningsprocess. Genom att studera avdunstningen av polymer-lösningar och binära lösningsmedelslösningar, genom förändringen i vikt när lösningsmedlet avdunstar och avdunstningshastigheten, kan potentiella samband identifieras. Resultaten indikerar att närvaron av polymerer påverkar lösningsmedlets avdunstning, där polystyren (PS) generellt accelererar och polymetylmetakrylat (PMMA) antingen decelererar eller har minimal inverkan på avdunstningshastigheterna. Binära lösningsmedelsblandningar visade icke-proportionella ökningar i avdunstningstider, vilket tyder på komplexa intermolekylära interaktioner, men inga tydliga mönster mellan deras egenskaper och avvikelser i avdunstningsprocessen kunde identifieras. Ytterligare forskning behövs för att finna möjliga samband för att kunna förutsäga avdunstningsprocessen. Dessa fynd understryker vikten av att förstå polymer-lösningsmedelskompatibilitet och avdunstningsdynamik för att förbättra effektiviteten och kunna identifiera miljövänliga lösningsmedel för tillverkning av organiska solceller (OPV).

Organic electronics based on π-conjugated semi-conductor raises new technology, such as organic film transistors, e-paper, and organic photovoltaic cells that can be implemented cost-effectively on large-area applications. Currently, the device performance is limited by low charge carrier mobility. Poly(3-hexylthiophene) (P3HT) and organic field effect transistors (OFET) is used as a model to investigate morphology of the organic film and corresponding electronic properties. In this thesis, processing parameters such as boiling points and solubility are controlled to impact the micro- and macro-morphology of the film to enhance the charge transport of the device. Alternative approach to improve ordering of polymer chains and increase in charge transport without post-treatment of P3HT solution is studied. The addition of high boiling good solvent to the relatively low boiling main solvent forms ordered packing of π-conjugated polymers during the deposition process. We show that addition of 1% of dichlorobenzene (DCB) to the chloroform based P3HT solution was sufficient to improve wetting and molecular structures of the film to increase carrier mobility. Systematic study of solvent-assisted re-annealing technique, which has potential application in OFET encapsulation and fabrication of top-contact OFET, is conducted to improve mobility of OFET, and, to suggest a cost-effective processing condition suitable for industrial application. Three process parameters: boiling point, polarity, and solubility are investigated to further understand the trend of film response to the solvent-assisted technique. We report the high boiling non-polar solvents with relatively high RED values promote highest improvement in molecular packing and formulate crystalline structure of the thin film, which increases the device performance.