Download Dissertation Abstract Electromagnetic wave absorption EMA materials are drawing extensive attention because of increasing electromagnetic pollution in daily life as well as military requirements for stealth weapon systems. Due to low density, high strength and excellent electrical property, carbon materials are suitable candidates for EMA materials.
Carbon nanotubes, gold particles and synthetic polymers are used for this purpose. This immobilization has been achieved predominantly by adsorption or by chemical binding and to a lesser extent by incorporating these objects as guests in host matrices. In the guest host systems, an ideal method for the immobilization of biological objects and their integration into hierarchical architectures should be structured on a nanoscale to facilitate the interactions of biological nano-objects with their environment.
Due to the large number of Rubber composites thesis or synthetic polymers available and the advanced techniques developed to process such systems to nanofibres, rods, tubes etc.
DEVELOPMENT IN THERMOFORMING THERMOPLASTIC COMPOSITES Robert M. Stack and Francis Lai University of Massachusetts Lowell composites with the same fiber percentage [7, 14]. These materials are commonly produced with rubber hose, pipe, building panels, and electrical insulators . This. A Study of the Erosion Mechanisms of Silicone Rubber Housing Composites by Refat Ghunem A thesis presented to the University of Waterloo in fulfillment of the. Different industries have different needs in the manufacturing of carbon fiber composites. The Composites Manufacturing and Simulation Center (CMSC) works with a range of industries to ensure they have the control of material microstructure to achieve specific stiffness and .
To come down in diameter into the range of several hundreds of nanometers or even down to a few nanometers, Electrospinning is today still the leading polymer processing technique available. The electric charges, which are accumulated on the surface of the droplet, cause droplet deformation along the field direction, even though the surface tension counteracts droplet evolution.
In supercritical electric fields, Rubber composites thesis field strength overbears the surface tension and a fluid jet emanates from the droplet tip. The jet is accelerated towards the counter electrode. During this transport phase, the jet is subjected to strong electrically driven circular bending motions that cause a strong elongation and thinning of the jet, a solvent evaporation until, finally, the solid nanofibre is deposited on the counter electrode.
Bio-hybrid polymer nanotubes by wetting[ edit ] Electro spinning, co-electrospinning, and the template methods based on nanofibres yield nano-objects which are, in principle, infinitively long.
For a broad range of applications including catalysis, tissue engineering, and surface modification of implants this infinite length is an advantage.
But in some applications like inhalation therapy or systemic drug delivery, a well-defined length is required. The template method to be described in the following has the advantage such that it allows the preparation of nanotubes and nanorods with very high precision.
The method is based on the use of well defined porous templates, such as porous aluminum or silicon. The basic concept of this method is to exploit wetting processes.
A polymer melt or solution is brought into contact with the pores located in materials characterized by high energy surfaces such as aluminum or silicon. Wetting sets in and covers the walls of the pores with a thin film with a thickness of the order of a few tens of nanometers.
Gravity does not play a role, as it is obvious from the fact that wetting takes place independent of the orientation of the pores relative to the direction of gravity.
The exact process is still not understood theoretically in detail but its known from experiments that low molar mass systems tend to fill the pores completely, whereas polymers of sufficient chain length just cover the walls. This process happens typically within a minute for temperatures about 50 K above the melting temperature or glass transition temperature, even for highly viscous polymers, such as, for instance, polytetrafluoroethyleneand this holds even for pores with an aspect ratio as large as 10, The complete filling, on the other hand, takes days.
The diameter of the nanotubes, the distribution of the diameter, the homogeneity along the tubes, and the lengths can be controlled. Applications[ edit ] The nanofibres, hollow nanofibres, core—shell nanofibres, and nanorods or nanotubes produced have a great potential for a broad range of applications including homogeneous and heterogeneous catalysis, sensorics, filter applications, and optoelectronics.
Here we will just consider a limited set of applications related to life science. Tissue engineering[ edit ] This is mainly concerned with the replacement of tissues which have been destroyed by sickness or accidents or other artificial means.
The examples are skin, bone, cartilage, blood vessels and may be even organs. This technique involves providing a scaffold on which cells are added and the scaffold should provide favorable conditions for the growth of the same.
Nanofibres have been found to provide very good conditions for the growth of such cells, one of the reasons being that fibrillar structures can be found on many tissues which allow the cells to attach strongly to the fibers and grow along them as shown.
Nanoparticles such as graphene,  carbon nanotubes, molybdenum disulfide and tungsten disulfide are being used as reinforcing agents to fabricate mechanically strong biodegradable polymeric nanocomposites for bone tissue engineering applications. The results suggest that mechanical reinforcement is dependent on the nanostructure morphology, defects, dispersion of nanomaterials in the polymer matrix, and the cross-linking density of the polymer.
In general, two-dimensional nanostructures can reinforce the polymer better than one-dimensional nanostructures, and inorganic nanomaterials are better reinforcing agents than carbon based nanomaterials.
Delivery from compartmented nanotubes[ edit ] Nano tubes are also used for carrying drugs in general therapy and in tumor therapy in particular. The role of them is to protect the drugs from destruction in blood stream, to control the delivery with a well-defined release kinetics, and in ideal cases, to provide vector-targeting properties or release mechanism by external or internal stimuli.Silica-Reinforced Natural Rubber for Low Rolling Resistance, Energy-Saving Tires: Aspects of Mixing, Formulation and Compatibilization, Ph.D.
Thesis, University of Twente, Enschede, the Netherlands, and Prince of Songkla University, Pattani Campus, Thailand. FREE-SPACE MICROWAVE CHARACTERISTICS OF NATURAL RUBBER COMPOSITES FILLED WITH CARBON BLACK FOR MICROWAVE APPLICATION BY AZLINDA BINTI RAMLI Thesis Submitted to the School of Graduate Studies, Universiti Putra Malaysia.
composites can possess enhanced strength, stiffness and fracture, toughness whilst not exhibiting an increase in weight. Composites are being used for prefabricated, portable and modular buildings as well as for exterior cladding panels.
RESEARCH AND TEACHING AREAS Research interest in natural fibre reinforced polymer composites, Thesis B. Eng (Hons kenaf and glass fibre reinforced rubber composites. 2. Mohd Aidil Ahmad: The tensile and flexural properties of hybrid oil palm fruit bunch (OPFB) and glass fibre reinforced polymer/rubber composite.
Post treatment of composites and laminates by heating or with high energy radiation, using a Co60 source, improved the quality of adhesion still further by the formation of more chemical links between polyaramid and rubber though some degradation of rubber strength simultaneously took place.
The EMI shielding effectiveness of rubber composites was analyzed using the measurement setup indicated in Figure 1 in frequency range from 1 GHz to 12 GHz.
Composite samples of 2 mm thickness were used. PhD Thesis. the Graduate School of Clemson University, Clemson.