Dentre tantas matérias primas existentes para produção de biodiesel, os óleos e gorduras residuais apresentam-se como uma alternativa promissora em função das questões ambientais envolvidas no seu reaproveitamento. Neste contexto, vários aspectos necessitam ser melhores compreendidos quanto à produção e utilização de biodiesel produzido a partir desta matéria prima. Dentre eles, destacam-se a estabilidade à oxidação do biodiesel e as suas conseqüências para o óleo lubrificante do motor, pois um combustível com baixa estabilidade à oxidação remete à menor vida útil do mesmo, enquanto que a presença de biodiesel no lubrificante degrada a qualidade do óleo, interferindo diretamente nas condições de desgaste das partes móveis do motor. Desta forma, esta pesquisa tem como objetivo propor uma metodologia de análise para identificar as conseqüências do uso de biodiesel de óleos e gorduras residuais em motores, a partir da adição ou não de um anti-oxidante no combustível, bem como avaliar a influência deste anti-oxidante sobre a estabilidade à oxidação do biodiesel. Para tanto, a pesquisa propõe a realização de ensaios em motores de ciclo diesel abastecido com biodiesel, sem troca de óleo, em condições reais de funcionamento, na presença e na ausência de anti-oxidante. Além disso, é proposto que a concentração do antioxidante a ser usado seja determinada a partir do acompanhamento do índice de peróxido do combustível e que o efeito deste anti-oxidante seja avaliado a partir da caracterização do combustível antes e após a sua aplicação. Quanto às conseqüências tribológicas do uso de biodiesel em motores, é proposto um monitoramento das variáveis físico-químicas do lubrificante, além de espectroscopia no infravermelho e por emissão ótica. Para identificar as relações existentes entre o combustível utilizado, o desgaste observado e a contaminação do óleo lubrificante, a metodologia proposta sugere a aplicação de uma matriz de correlação nos resultados obtidos. No presente estudo, a metodologia foi aplicada em um motor de ciclo diesel estacionário, acoplado à um gerador de 12,5 kVA, trabalhando por intervalos de tempo superiores à 250 h. Os resultados mostraram que a adição de BHA como agente anti-oxidante aumenta a estabilidade à oxidação do biodiesel para uma concentração de 1000 ppm, Além disso, também foi possível identificar que ocorreu contaminação do lubrificante pelo biodiesel, na presença ou não de BHA, e que esta contaminação apresentou alguma influência nas condições tribológicas do motor para o período de ensaios considerado. / Amongst many available sources for biodiesel production, the residual oils and fats are presented as a promising alternative by the environmental questions involved in its reuse. This way, some aspects related to biodiesel production and utilization must be better understood. Amongst them, it is highlighted the oxidation stability of biodiesel and its consequences to the engine lubricant oil, because a fuel with low oxidation stability sends to a lesser useful life whereas the presence of biodiesel in the engine lubricant degrades the oil quality, intervening directly with the wearing conditions of the engine mobile parts. In such a way, this research proposes an analysis methodology to identify the consequences of the biodiesel use in engines, in the presence or not of the antioxidative substance, as well to evaluate the influence of an antioxidative substance on the oxidation stability of biodiesel. For that, the research considers the accomplishment of the assays in a diesel engine, without oil exchange, in real conditions of working, in two stages: in the presence and without the antioxidative substance in the fuel. Moreover, it is proposed that the concentration of the antioxidative substance to be used must be evaluated by the accompaniment of the fuel peroxide index and that the effect of this antioxidative substance must be evaluated from the characterization of the fuel before and after its application. About the tribologycal consequences of the biodiesel use in engines, it is proposed a monitoring of the lubricant physical-chemical variables, beyond spectrometry in the infra-red ray and optical emission spectroscopy. To identify the relations between the fuel used, degree of wearing and lubricant oil contamination, the methodology suggests the application of a matrix of correlation in the achieved results. In the present study, the methodology has been applied in a stationary diesel engine coupled to a generator of 12,5 kVA, by a period bigger than 250 h. The lubricant used was SAE 15W40 oil. The results had shown that the BHA addition increases the biodiesel oxidation stability for a 1000 ppm concentration. Moreover, it was also possible identify that contamination lubricant by biodiesel occurs, in the presence or not of BHA, and that this contamination presented some influence on the engine tribologycal conditions for the period of assays considered.

Dentre tantas matérias primas existentes para produção de biodiesel, os óleos e gorduras residuais apresentam-se como uma alternativa promissora em função das questões ambientais envolvidas no seu reaproveitamento. Neste contexto, vários aspectos necessitam ser melhores compreendidos quanto à produção e utilização de biodiesel produzido a partir desta matéria prima. Dentre eles, destacam-se a estabilidade à oxidação do biodiesel e as suas conseqüências para o óleo lubrificante do motor, pois um combustível com baixa estabilidade à oxidação remete à menor vida útil do mesmo, enquanto que a presença de biodiesel no lubrificante degrada a qualidade do óleo, interferindo diretamente nas condições de desgaste das partes móveis do motor. Desta forma, esta pesquisa tem como objetivo propor uma metodologia de análise para identificar as conseqüências do uso de biodiesel de óleos e gorduras residuais em motores, a partir da adição ou não de um anti-oxidante no combustível, bem como avaliar a influência deste anti-oxidante sobre a estabilidade à oxidação do biodiesel. Para tanto, a pesquisa propõe a realização de ensaios em motores de ciclo diesel abastecido com biodiesel, sem troca de óleo, em condições reais de funcionamento, na presença e na ausência de anti-oxidante. Além disso, é proposto que a concentração do antioxidante a ser usado seja determinada a partir do acompanhamento do índice de peróxido do combustível e que o efeito deste anti-oxidante seja avaliado a partir da caracterização do combustível antes e após a sua aplicação. Quanto às conseqüências tribológicas do uso de biodiesel em motores, é proposto um monitoramento das variáveis físico-químicas do lubrificante, além de espectroscopia no infravermelho e por emissão ótica. Para identificar as relações existentes entre o combustível utilizado, o desgaste observado e a contaminação do óleo lubrificante, a metodologia proposta sugere a aplicação de uma matriz de correlação nos resultados obtidos. No presente estudo, a metodologia foi aplicada em um motor de ciclo diesel estacionário, acoplado à um gerador de 12,5 kVA, trabalhando por intervalos de tempo superiores à 250 h. Os resultados mostraram que a adição de BHA como agente anti-oxidante aumenta a estabilidade à oxidação do biodiesel para uma concentração de 1000 ppm, Além disso, também foi possível identificar que ocorreu contaminação do lubrificante pelo biodiesel, na presença ou não de BHA, e que esta contaminação apresentou alguma influência nas condições tribológicas do motor para o período de ensaios considerado. / Amongst many available sources for biodiesel production, the residual oils and fats are presented as a promising alternative by the environmental questions involved in its reuse. This way, some aspects related to biodiesel production and utilization must be better understood. Amongst them, it is highlighted the oxidation stability of biodiesel and its consequences to the engine lubricant oil, because a fuel with low oxidation stability sends to a lesser useful life whereas the presence of biodiesel in the engine lubricant degrades the oil quality, intervening directly with the wearing conditions of the engine mobile parts. In such a way, this research proposes an analysis methodology to identify the consequences of the biodiesel use in engines, in the presence or not of the antioxidative substance, as well to evaluate the influence of an antioxidative substance on the oxidation stability of biodiesel. For that, the research considers the accomplishment of the assays in a diesel engine, without oil exchange, in real conditions of working, in two stages: in the presence and without the antioxidative substance in the fuel. Moreover, it is proposed that the concentration of the antioxidative substance to be used must be evaluated by the accompaniment of the fuel peroxide index and that the effect of this antioxidative substance must be evaluated from the characterization of the fuel before and after its application. About the tribologycal consequences of the biodiesel use in engines, it is proposed a monitoring of the lubricant physical-chemical variables, beyond spectrometry in the infra-red ray and optical emission spectroscopy. To identify the relations between the fuel used, degree of wearing and lubricant oil contamination, the methodology suggests the application of a matrix of correlation in the achieved results. In the present study, the methodology has been applied in a stationary diesel engine coupled to a generator of 12,5 kVA, by a period bigger than 250 h. The lubricant used was SAE 15W40 oil. The results had shown that the BHA addition increases the biodiesel oxidation stability for a 1000 ppm concentration. Moreover, it was also possible identify that contamination lubricant by biodiesel occurs, in the presence or not of BHA, and that this contamination presented some influence on the engine tribologycal conditions for the period of assays considered.

No description available.

Lubricants additives are inseparable component of modern high-tech lubricants. Viscosity index improvers additives play uncoverable role in a branch of boundary lubrication. They are designed to ensure sufficient oil film thickness in low speeds of frictional surfaces motion. This thesis deal with effect of specific viscosity index improvers additives on boundary lubrication film formation in elliptical contact. The purpose of this work is also checking the effect of concentration changing these additives on lubricantion film thickness formation.

A potential alternative to acrylonitrile-butadiene-styrene (ABS) and polycarbonate+ABS (PC+ABS), pigmented mineral-filled polypropylene (PP) finds an opening in automotive interior components such as instrument panels, knee bolsters, consoles, etc. Because of the lack of surface aesthetics, pigmented mineral-filled PP is experiencing a limitation to its acceptance in many applications. This study focuses on exploring various mineral fillers and additives in polypropylene to provide a material with enhanced scratch resistance. Several physical properties including Rockwell and Shore D hardness are investigated, and it is determined that Filler W improves scratch resistance. It is also determined that Filler T-filled-PP has poor scratch resistance even with the addition of a lubricant.

Nynas AB is a company that refines oil  for different applications such as insulating oils  for the electrical industry and base oils for both the lubricant and chemical industry. Different types of base oils are produced for the lubricant industry in order to provide required properties such as good viscosity, solvency, volatility, etc. But sometimes, the oils produced in the refineries (known as “straight cut” oils) do not have the all properties required by a customer, and a way for achieving those properties is to blend different straight cut base oils. To save money and time, empirical correlations are used to facilitate the prediction of the properties of those blends.Those correlations are adapted to products from a single site produced from certain crude oils. The company has recently decided to introduce a new stream of products with different characteristics, which means that the new properties of the products and blends can not be predicted by using the existing empirical correlations. The objective of this project was to analyze blends containing these new products and find the new correlations. The names of the oils are classified information and were renamed in the report and also number of the tables with result in appendices has been reduced to protect Nynas AB.  The correlations were surprisingly good for most of the blends. The differences between the values obtained by the blending program (which was calculating the properties) and the experimental values were very small. But the calculated values for properties such as flash point and pour point, were quite different from the experimental ones for some of the samples. Finally, there was one type of blends, between the Naphthenic oil 2 (N 2) and Paraffinic oil B (P (B)), were it was not possible to get any results with the blending program, because the viscosities at 40 °C of those oils (N 2 and P(B)) were too similar. As mentioned before, the property that was most difficult to predict was the pour point, specially for blends containing paraffinic oil blend with a naphtenic oil. However, suggestions were made based on the experimental values of how to get correlations based on. Anyhow, empirical correlations were developed based on the experimental data.

Analysis of trace evidence involved in sexual assault investigations holds considerable potential as a newer avenue of identification when bulk, larger evidence is not found or unreliable. Trace analysis of forensic materials involves common findings such as strands of hair, residues left on clothing, shards of paint or glass, etc. In recent research focused on the analysis of trace materials found as evidence in a sexual assault, there has been promise in condom and bottled lubricant classification based on their chemical profiles that can provide an associative link in an investigation. Few studies have considered the examination of lubricant evidence at a trace level as it may be found on a crime scene or a victim. In this study, a new protocol will be tested and established to analyze trace lubricant evidence recovered from a fabric substrate, such as underwear, after sexual assaults using Fourier transform infrared (FTIR) spectroscopy. An experiment is proposed to examine the comparison of the spectra resulting from FTIR spectroscopic analysis of bulk and trace level lubricants recovered from a cotton substrate. The resulting spectra will be compared for their similarities using multivariate statistical techniques to test the viability of the approach.

No description available.

In recent years, the impact of humans on the environment has been the subject of much debate. Car companies in particular are among the main actors in this environmental degradation with the polluting aspect of combustion cars. However, in recent years, these companies have started to switch to electric cars in order to reduce their impact on the environment. This is the case for Volvo, for example, where electrification is a priority. With the goal of becoming a climate neutral company by 2040, Volvo is driving innovation to reduce the use of polluting materials, such as oil.  Oil is not only used to power cars, but also in the fluids used to cool electrical machines or lubricate transmissions. However, alternatives to these fluids have emerged in recent years, such as glycerol-based or water-based lubricants. This Master Thesis aims to follow the evolution of water-based lubricants, but also to compare the performance of existing fluids within electric drivelines.  Water is known to have very good thermal properties but also to have a high electrical conductivity, which represents a big challenge for the use of this type of lubricant within an electric machine. It is with the aim of evaluating the impact of these properties that the following study investigates the electrical compatibility of a water-based lubricant within an electrical machine. The thermal performance of this type of fluid is also investigated and compared to that of an oil- based fluid also studied at Volvo. This master thesis will serve as a springboard for further studies of these lubricants, and will also raise questions and challenges that need to be addressed in the future in order to be able to take full advantage of the properties of these water-based lubricants.

Most of the rolling element bearings are lubricated with Grease lubricant. Generally, the grease is expected to serve for life. The major causes of the bearing failure are due to the failure of the lubrication. The grease will experience creeping, oil permeation, oil separation etc. The separated oil will be lost permanently from the bearing. The widely used grease for general application is the lithium grease. The thickener of the grease consists covalent bond. When the grease is sheared, the breakage of the covalent bond will be permanent, resulting in the permanent loss of the rheological properties. The gels have unique properties such as thermal reversibility, viscoelasticity and thixotropy. They become mobile under shear stress and solidify again when the shear stress is removed. This property can be harnessed to avoid the base oil creeping, oil permeation, leakage in gears and bearings. Due to the presence of the polar group in the gels, they form a good tribo film and prevent the wear.  Under the shear stress, weak supramolecular interactions will be distorted, and this leads to the release of the oil and they re-form the structure after a certain period of rest. When the gel is in the solid-state, it will avoid creeping and evaporation. Many classes of gels are either derived from natural sources or from environmentally friendly materials. Thus, the lubricant formed out of gel would effectively solve both environmental as well as lubrication problems. In this work, supramolecular gel lubricants were prepared out of fully green, cellulose derivatives and starch hydrolysates. The non-ionic hydroxyethyl cellulose (HEC) and anionic sodium carboxymethyl cellulose (NaCMC) were chosen to understand the effect of ionic and non-ionic gelators on the rheological and the tribological parameters. Traditionally fat was used as a lubricant, now, in food industry various fat replacers are being used. To study whether the fat replacers can act as a thickener, Dextrin and maltodextrins were chosen.  Dextrin and maltodextrin with the different DE values were selected to understand the influence of molecular weight on gelation and tribological performance.  Inspired by the recent developments and advantages of aqueous lubrication, mixer of water and poly(ethylene glycol) 200 (PEG 200) is chosen as the base fluid. It was found that a very small amount of gelator can increase the viscosity of the PEG/water to several orders. The thermal stability of the gels was studied using thermogravimetric analysis (TGA) and found that gels can increase the thermal stability of the base fluid. FTIR results showed the formation of a non-covalent bond between the PEG molecules and water. It is shown that anionic gelator will result in producing low friction and wear in comparison to non-ionic gelator. The possible tribo-film formation due to the negative charge in the NaCMC molecules is attributed to these results. The very low friction and low wear was exhibited by the dextrin and maltodextrin gels. It is proposed that this could be due to the microspherical particles of gels which can act as nano bearings. It was found that choosing the optimum concentration of the gelator is important to reduce friction and wear. The higher gelator concentration will form the hard gel, which cannot flow and replenish the sliding contact, resulting in the starved lubrication. This will cause high wear and friction. These gel lubricants can be used in food, pharmaceutical and biomedical industries.