A method to measure the mixed-mode fatigue behavior of environmentally degraded adhesive joints was developed. Firstly, the absorption and desorption of water in two different rubber-toughened epoxy adhesives was measured gravimetrically. The water absorption in both adhesives showed anomalous behavior that was fitted to a new “sequential dual Fickian” (SDF) model. The water desorption in both adhesives was modelled accurately using Fick’s law, and there was a significant difference in the amount of retained water after drying in the two adhesives. The effects of long-term aging were studied using open-faced specimens made with two different rubber-toughened epoxy adhesives. The contrasting results illustrated the effects of environmental degradation on the matrix and toughener. Furthermore, the differences in the degradation behavior of both adhesives, combined with gravimetric and dynamic mechanical thermal analysis (DMTA) results, were used to illustrate the role of retained water in degrading the toughening mechanisms. The measured fatigue results invalidated the environmental index (EI) hypothesis for fatigue behavior, at least for the relatively short aging times studied here. Compared with aging under constant humidity, the fatigue performance of joints was found to be superior after aging in a cyclic salt-spray environment due to the lower water concentrations in the adhesive. The effects of test environment humidity and temperature on the fatigue behavior were also studied using closed, un-aged specimens. Both individual and combined effects of temperature and humidity on fatigue behavior were studied. In elevated temperature and humidity environment, joint performance at higher crack growth rates was degraded solely due to the effect of the increased temperature, whereas fatigue performance at low crack growth rates degraded predominantly because of elevated moisture. Finally, to generalise the techniques developed to automotive aluminum sheets, a reinforced specimen was developed that avoids yielding of thin aluminum sheet adherends while loading. Fatigue testing with these reinforced specimens revealed that the fatigue behavior was sensitive to the loading phase angle and the orientation of rolling lines on the sheet. These reinforced specimens were also used to study the effects of long-term aging and the effects of test environment.

This thesis systematically investigates the properties of the aluminium adherend which influence the fracture toughness of aluminium-epoxy adhesive joints in humid environments. The fracture energy of the adhesive joint exposed to a humid environment in comparison with the fracture energy in a dry environment provides a measure of the joint durability. A 500C and 95% relative humidity environment is used to simulate aging of an adhesive joint over several years under normal service conditions. Initially, surface roughness is found to have a significant influence on the fracture toughness of the adhesive joint in humid conditions. A direct correlation between the bond durability and the angle of deliberately machined micro-roughness in the aluminium surface is determined. Consequently a model is developed which initially has the capacity to describe the bond durability performance. The preparation of aluminium surfaces involves the use of a novel ultramilling tool to produce well defined and controlled surface topography. This work represents the first time surface angles of features in the 1????m to 10????m range have been systematically varied and a direct relationship with bond durability has been determined. The use of surface analytical tools aids in elucidating mechanisms involved in the failure of the adhesive joint and contributes to the development of the stress based diffusion model. Examination of the aluminium oxide hydration level reveals this property has a negligible effect on the fracture toughness of the aluminium-epoxy joints exposed to humid environments. This information confirms the dominant role of the physical properties of the aluminium surface in determining the adhesive joint durability. This is the first occasion that planer oxide films grown in an RF plasma have had their hydration state adjusted in a controlled manner and their properties subsequently assessed in terms of bond durability properties. Further alteration of the aluminium surface chemistry is achieved through the application of an organo-silane coupling agent and a series of novel organo-phosphonate compounds. This work further develops the stress based diffusion model developed in conjunction with the micro-machining studies. The components of surface roughness and the ability of interfacial bonds to co-operatively share load are essential for the maintenance of fracture toughness of adhesive joints exposed to humid conditions. The ability of the silane coupling agent to share load through a chemically cross-linked film is a significant property which provides the superior fracture toughness in comparison with the phosphonate treated joints. Although the organo-phosphonate treated aluminium provides hydrolytically more stable bonds than the silane coupling agent, the film is not cross-linked via primary chemical bonds and the reduced load sharing capacity of interfacial bonds increases the bond degradation rate. The stress based diffusion model evolving from the initial work in the thesis can be used to predict the performance of more complex systems based on a thorough characterisation of the aluminium surface chemistry and topography. The stress based diffusion model essentially describes the concept of the production of micro-cavities at the epoxy-aluminium interface under mode 1 load, as a result of the distribution of strong and weak adhesive bonds. Alternatively, micro-cavities may result from an inhomogeneous stress distribution. In areas where the adhesive bonds are weak, or the local stresses are high, the interfacial load produces larger micro-cavities which provide a path of low resistance for water to diffuse along the bond-line. The water then degrades the adhesive bond either through the displacement of interfacial epoxy bonds or the hydration of the oxide to form a weak barrier layer through which fracture can occur. Alternatively, the water can hydrolyse the adhesive in the interfacial region, leading to cohesive failure of the epoxy resin. The bond durability performance of a series of complex hydrated oxide films used to pre-treat the aluminium adherend provides support for the stress based diffusion model. Whilst surface area is an important property of the aluminium adherend in producing durable bonding, the best durability achievable, between an epoxy adhesive and aluminium substrate, requires a component of surface roughness which enhances the load sharing capability in the interfacial bonding region. This component of durability performance is predicted by the model. In more specific terms, a boiling water treatment of the aluminium adherend indicates a direct correlation between bond durability, surface area and topography. The characterisation of film properties indicates that the film chemistry does not change as a function of treatment conditions, however, the film topography and surface area does. The overall bond durability performance is linked to both of these properties. The detailed examination of the hydrated oxide film, produced by the boiling water treatment of aluminium, is the first time the bond durability performance has been related to the film topography. It is also the first occasion that the mechanism of film growth has been examined over such a large treatment time. The combination of surface analysis and bond durability measurements is invaluable in confirming the properties, predicted by the stress based diffusion model, which are responsible in forming fracture resistant adhesive bonds in humid conditions. The bond durability of high surface area and low surface area hydrated oxide films indicates that surface area is an important property. However, this study confirms that the absence of the preferred surface topography limits the ultimate bond durability performance attainable. The fracture toughness measurements performed on aluminium adherends pre-treated with a low surface area film also supports the mechanism of load sharing of interfacial adhesive bonds and its contribution to the overall bond durability. The role performed by the individual molecules and particles in an oxide film is similar to the load sharing performed by the silane coupling agent molecules. Further support for the stress based diffusion model is provided by films produced on aluminium immersed in nickel salt solutions. The topography of these film alters as a function of treatment time and this is directly related to fracture toughness in humid environments. This work provides the first instance where such films have been characterised in detail and their properties related to bond durability performance. The study is also the first time that the growth mechanism of the film produced on the aluminium substrate has been examined in detail. The film growth mechanism supports the film growth model proposed for the hydrated oxide film produced by the boiling water treatment. The major findings presented in this thesis are summarised as the direct correlation between surface profile angle, the importance of co-operative load sharing of interfacial adhesive bonds and the relative insignificance of surface oxide hydration in the formation of durable aluminium-epoxy adhesion. This information is used to develop a stress based diffusion model which has the capacity to describe the fracture toughness of a range of aluminium-epoxy adhesive joint systems in humid environments. The stress based diffusion model is also capable of predicting the relative performance of the bond systems examined in the final chapters of the thesis, where complex interfacial oxide films are involved in the formation of adhesive bonds.

Background: Frozen shoulder or idiopathic adhesive capsulitis is an enigma of musculo-skeletal medicine. It is a difficult condition to treat and its etiology is still unknown. Aim: The aim of this study is to investigate whether acupuncture has a role in the management of frozen shoulder. Objectives: An in-depth literature review was conducted on all aspects related to the current concepts and treatments for frozen shoulder. Although there were discussions on associated conditions and possible causes of frozen shoulder, there is currently no consensus on its management. Acupuncture has been used successfully as a treatment for frozen shoulder by many eastern practitioners. Unfortunately, their claims could not be substantiated due to a lack of properly conducted clinical trials. An acupuncture treatment protocol for the management of frozen shoulder was designed based on both Traditional Chinese Medicine (TCM) and Anatomical principles. This protocol was then tested with a clinical trial. Methods: A pilot study, using a prospective case series of 20 patients suffering with the “adhesive phase” of frozen shoulder, was conducted to test the effectiveness of the acupuncture treatment protocol. This study included specific selection and exclusion criteria; an objective assessment of the range of movement and subjective assessments on the quality of life and pain. All data were collated and analysed with SPSS version 12. The pretreatment and post-treatment data were tested using both parametric paired sample t test and non-parametric Wilcoxon signed-rank test. Results: The patients’ profile confirmed the affected age group and gender distribution to be similar to those in the literature search. Unfortunately, due to the small sample size, there were no significant associated conditions demonstrated. There were twice as many cases of primary frozen shoulder than secondary frozen shoulder in this study. These analyses suggested that there were significant changes in all three areas of assessment – range of shoulder movement, quality of life and visual analogue pain scale (p&lt0.001). At completion of treatment, the result revealed that the acupuncture treatment protocol was successful in 60%, and moderately successful in 15%, of the 20 cases tested. This outcome was compared with the study by Omari and Bunker which showed only 12% success with conservative western medical treatments, suggesting that acupuncture may be better than conservative western medical treatments. Conclusion: Acupuncture treatment is less costly and has minimal side effects. It should be part of the non-procedural modalities offered to patients suffering with frozen shoulder. For patients who have failed western conservative managements, a trial of acupuncture treatment should be considered prior to embarking on the more invasive interventions..

Thesis (M.S.)--Indiana University, Dept. of Kinesiology, 2006. / Includes bibliographical references.

Thesis (M.S.)--Indiana University, 2006. / Includes bibliographical references. Also available online (PDF file) by a subscription to the set or by purchasing the individual file.

Thesis (M.S.)--Humboldt State University, 2007. / Includes bibliographical references (leaves 30-34). Also available via Humboldt Digital Scholar.

Thesis (Ph. D.)--University of New South Wales, 1998. / Also available online.

Thesis (M.S.E.E.)--State University of New York at Binghamton, Watson School of Engineering and Applied Science, 2006. / Includes bibliographical references.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 107-109). Also available via the Internet.

Thesis (Ph. D.)--University of Rhode Island, 2004. / Typescript. Includes bibliographical references (leaves 105-107).