Adhesives future needs

Most of the chapters in this volume directly address the research needs expressed in Alan Lambuth s overview (Chapter 1). Although this book can only be representative of the much wider attack on the problem of obtaining adhesives from renewable resources, it does demonstrate that research is currently underway in industry, universities, and government laboratories that is focused on a critical future need of industry. 

If one examines the future needs of high performance IC processing (Table 1.3), more than seven levels of interconnects may be required. Such schemes will be implemented using CMP methods to planarize at each level. Estimate the impact of building multilayers on stresses in underlying layers and its and CMP s impact on adhesion stability requirements. 

To meet increasing high-temperature demands during processing caused by the future use of lead-free solders, future adhesives will need to be based on very-high-temperature materials such as anhydride-cured epoxies and bismaleimides. 

These thoughts and suggestions are industrially oriented, to be sure. They arise from practical need and reflect concern for future adhesive supply. Collectively, the various forms of wood utilization represent an extremely large and diverse market for adhesives, probably the largest in the world today. Thus, industrial comments seem appropriate. Apart from identified needs, however, the wood products industry recognizes the value of research into the chemical structure and adhesive mechanisms of natural polymers unrelated to current problems. The next echelon of technical development can be expected to arise from this research. It is also acknowledged that certain of the adhesive performance characteristics requested cannot be accomplished with the current level of scientific information. Finally, it is the wood products industry s view that natural adhesives and resources will inevitably play an important part in its future. Thus, they represent a significant and potentially productive area for current adhesive research. 

Since the energy and chemical raw material crunch of 1973, many alternatives to petroleum and other imported chemical stocks have been explored. What are the needs of the adhesive industry What other sources can be tapped Cellulose, a polysaccharide produced in great abundance in nature, is a prime candidate as a raw material for use in adhesives because of its availability and relatively low cost and because of its readiness to be converted into a variety of useful adhesive products. In essence, cellulose is a wonder material with a promising future (i). 

Adhesives derived from natural resources and the possibilites for their industrial utilization, particularly in the forest products industry, have been a focus of considerable attention in recent times. While such adhesives have been used for most of mankind s history, substantial progress has been made in the last 15 years in producing durable adhesives from renewable resources that come close to meeting today s exacting industry standards. A number of important opportunities exist for further refinement of promising adhesive systems and for the development of new ones. Recent advances demonstrate the breadth of available possibilities for using nature s own storehouse for adhesive production and offer an excellent starting point for future research effort needed for its optimum exploitation. 

Pyridine derivatives are precursors of many chemical products of medicinal, agricultural, and industrial importance. Pyridine itself is used not only as a solvent, but also as a starting material for pharmaceuticals, herbicides, insecticides, and fungicides. a-Picoline is a precursor for 2-vinylpyridine which is used in the production of an adhesive for textile tire cord. The major use of y-picoline is in the production of isonicotinic hydrazide, an antituberculosis agent. / -Picoline and 2-methyl-5-ethylpyridine are important intermediates in the production of two members of the vitamin B family, nicotinamide, and nicotinic acid (also known as vitamin B3). All this shows there is a substantial need for the production of picolines. The following text describes a novel route to a-picoline which might in the future lead to new processes. 

Safety in the use of chemicals will lead to sustainable development. In communities of all sizes in all countries, the question is the way we are living today sustainable is being asked. Communities have to ensure that they meet today s needs without compromising the ability of the environment to sustain life in the future. Toxic chemicals do have an important place in a sustainable environment, and toxic does not mean unacceptable , otherwise biocides would not be used — and in today s societal requirements, preservation of foods, paper, textiles, adhesives, paints, and many other commodities, is vital. 

Thin Film Cells. Future, lower cost solar cell materials will likely be more flexible than crystalline silicon and therefore may not require a rigid member In the module lay up. They will still need electrical Isolation and protection fradhesive layers as well as outer covers/insulators. 

The discovery of a highly active family of catalysts based on iron, a metal that had no previous track record in this field, has highlighted the possibilities of further new catalyst discoveries. The search for new catalysts be restricted to metals that have a history of giving polymerization-active centers was no longer needed. The LTMs especially are likely to provide fertile ground for future development, and the greater functional group tolerance of the LTMs also offers the attractive prospect of polar co-monomer incorporation. A relatively small amount of functionality can dramatically transform the adhesion and wettability properties of polyolefins more heavily functionalized products offer the prospect of materials with totally new properties and performance parameters. It is clear that, for olefin polymerization catalysis, the process of catalyst discovery and development is far from over. 

This article discusses briefly the use of adhesives on the construction site in the context of structural repair and reinforcement the requirements and practical dilficulties in the work on site with regtirds to the strength and durability of the rehabilitated timber structure and the consequent need for queility control. It also highlights the characteristics and requirements that must be fidfilled by structural adhesives and reinforcing materials factors affecting performance and durability of bonded joints tmd ways to improve adhesion and durability. Finally, it points out some research needs and future developments identified by the authors. 

The surfaces of devices often exhibit different wettability characteristics, depending on the manufacturing approach adopted. Surface modification techniques can be used to alter the wettability behavior of microfluidic devices. This difference in wettability can be used to control the flow rate in devices. There are many other benefits of hydrophilic surface treatments, including the ability to increase adhesion and capillary effects [2]. Irrespective of the material used in the device, the primary requirement that a material needs to fulfill is biocompatibifity in various applications. Therefore, it is also necessary to use surface modification techniques to render materials biocompatible. It is believed that future devices of increasing sophistication will often require programmable surface properties, including control of the spatial distribution of charge and polarity [3]. 

---