In this thesis, several methods of material integration into organic photovoltaic devices are investigated by fabricating solution processed and vacuum coated devices. Each of these methods is aimed at examining and improving one or more of the four critical factors that determine solar cell efficiency: (1) photovoltage, (2) light absorption, (3) exciton separation, and (4) …
Category Archive: Plastics Technology
Plastics Technology Paper
Mar
12
Modification and evaluation of fuel cell membranes
The primary goals of this study were modification of existing NafionRTM membranes and characterization of newly developed hydrocarbon-based membranes for high temperature fuel cell applications. Various NafionRTM/silicate nanocomposites were formulated via in situ sol-gel reactions for tetraethylorthosilicate. Different silicate composition profiles generated across membrane cross-sections were investigated by EDAX/ESEM. Composite water uptake, proton conductivity and …
Mar
11
Self-repairable polymeric networks: Synthesis and network design
This dissertation describes the design, synthesis and development of a new class of polymeric networks that exhibit self-repairing properties under UV exposure. It consists of two parts: (a) modification and synthesis of oxetane (OXE), and oxolane (OXO) substituted chitosan (CHI) macromonomer, and (b) design, and synthesis of self-repairing polyurethane (PUR) networks consisting of modified chitosan. …
Mar
11
Computational Fluid Dynamics of a Gas-Solid Fluidized Bed at High Pressure
Computational fluid dynamics was used to study the effect of pressure on the hydrodynamic behaviour of a gas solid fluidized bed comprising Polyehtylene particles. Time average properties and dynamic characteristics on the fluidized bed were predicted by means of the Eulerian-Eulerian multiphase model in the computational fluid dynamic software FLUENT v 6.3. The effect of …
Mar
10
Constant temperature embossing of supercooled polymer films
In this dissertation work, a constant temperature embossing process was developed and investigated. By softening and crystallizing a supercooled polymer at the same temperature, the embossing and solidification stages can be carried out isothermally without thermal cycling. The new process was demonstrated for replicating rectangular trenches with different aspect ratio for two different polymers: PET …
Mar
09
Synthesis and characterization of photocurable poly(caprolactone) networks with shape memory effect
This thesis focuses on the synthesis of photocurable copolymers networks with shape memory effect. Copolymers of epsilon-caprolactone and a new lactone monomer modified with a cinnamoyl moiety that can be cross-linked by UV light were synthesized. Various copolymer architectures (random and block) were synthesized and confirmed by 1H NMR, DSC and UV-VIS spectroscopic techniques. These …
Mar
06
Constant temperature embossing of supercooled polymer films
In this dissertation work, a constant temperature embossing process was developed and investigated. By softening and crystallizing a supercooled polymer at the same temperature, the embossing and solidification stages can be carried out isothermally without thermal cycling. The new process was demonstrated for replicating rectangular trenches with different aspect ratio for two different polymers: PET …
Mar
04
Design of biodegradable aliphatic aromatic polyester films for agricultural applications using response surface methodology
Degradation of an aliphatic aromatic copolyester film, polybutylene adipate-co-terephthalate) or PBAT, under atmospheric, laboratory simulated solar radiation, phosphate buffer solution, manure, food and yard compost environments was investigated. Methodologies and equipment were developed to measure biodegradation of PBAT films in compost environments using a direct measurement respirometric system DMR), and to determine the gel content …
Feb
26
High temperature behavior of polypropylene and polypropylene / glass composites
Solid state die drawing of polymer matrix composite materials offers an opportunity to make products that cannot be produced by any other method. This is done by heating a composite billet to a temperature just below the melting point and drawing it through a heated converging die by pulling from the downstream side. Since this …
Feb
26
An Investigation of Surface Engineering Techniques to Minimize Wear of Thermoplastic Injection Mold Tooling
Wear and corrosion are significant industrial issues resulting in high financial losses. With continuously increasing demands placed on thermoplastic injection molded products with regards to increased mechanical properties, leading to the incorporation of highly abrasive fillers and corrosive additives, and narrow dimensional tolerances, the surface engineering techniques to increase wear and corrosion resistance and improve …