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Reviews the traditional use of thermoset (epoxy) adhesives for various bonding applications and highlights some limitations in today’s microelectronics arena. In…
Reviews the traditional use of thermoset (epoxy) adhesives for various bonding applications and highlights some limitations in today’s microelectronics arena. In particular, concerns for thermal and stress management associated with large area silicon bonded to a wide variety of substrate materials has led to an increasing interest in thermoplastic adhesive technology. Thermoplastics are not always the best solution for every application. This paper sets out to address the “pros and cons” of each polymer technology for different microelectronic applications taking into account some of the key physical properties such as Tg, TCE and modulus. In addition, practical issues such as handling, storage and processing are considered in detail.
The purpose of this paper is to investigate and present the properties of a new substrate material based on thermoplastic polymers (so‐called LuVo Board) for…
The purpose of this paper is to investigate and present the properties of a new substrate material based on thermoplastic polymers (so‐called LuVo Board) for high‐frequency applications.
The thermal, mechanical and electrical properties of a new thermoplastic substrate are investigated and compared to conventional substrates for printed circuit board (PCB) applications.
The new LuVo Board exhibits similar properties to commercially available high‐performance substrates. The main advantage of the LuVo Board is a reduction of manufacturing costs in comparison to conventional substrates, as a highly automated manufacturing process can be employed. Moreover, the LuVo Board exhibits some further advantages: the material is inherently flame resistant and can be thermally shaped after the assembly process.
This paper presents an entirely new thermoplastic substrate, which can be employed in high‐frequency applications. In comparison to standard materials, a further advantage of the thermoplastic substrate is lower production costs.
This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder…
This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder metallurgy and composite material processing are briefly discussed. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for 1994‐1996, where 1,370 references are listed. This bibliography is an updating of the paper written by Brannberg and Mackerle which has been published in Engineering Computations, Vol. 11 No. 5, 1994, pp. 413‐55.
The Packaging Revolution of the ’90s, powered by the perpetual drive for smaller‐faster‐cheaper products, is placing increasing demands on the electronic materials sector. Down‐sizing, without a cost penalty, requires new materials and processes. Electronic polymers are playing an increasingly vital rôle as area array, chip size components and packageless designs become mainstream technologies. Micro‐Ball Grid Arrays (micro‐BGA), Chip Scale Packages (CSP) and Chip‐on‐Board(COB) require new adhesives and encapsulants that enable the use of low‐cost, high density organic‐based wiring and interconnect structures. Concurrently, new, simplified processes are being developed in order to streamline high volume manufacturing. This paper discusses quick bonding film die attach adhesives, fast‐flow flip‐chip underfills, and a variety of liquid encapsulants as well as new conductive adhesives designed for flip‐chip and micro‐Package assembly. Process innovations include the new Printed Package concept and the appealing simple Polymer Dip Chip method of flip‐chip assembly without paste deposition. The intrinsic versatility and synergy afforded by new and emerging electronic polymers are helping the industry meet the seemingly paradoxical challenge of smaller‐faster‐cheaper.
Fire retardant oil‐modified alkyd resin based on chlorendic ahnydride (1,4,5,6,7 7‐hexachlorobicyclo‐(2,2,1) hept‐5‐ene‐2,3‐dicarboxylic anhydride) have been synthesized…
Fire retardant oil‐modified alkyd resin based on chlorendic ahnydride (1,4,5,6,7 7‐hexachlorobicyclo‐(2,2,1) hept‐5‐ene‐2,3‐dicarboxylic anhydride) have been synthesized using linseed oil, phthalic anhydride and glycerol. Several paint formulations were designed to study the effect of pigment/binder ratio, antimony trioxide and chlorinated thermosetting and thermoplastic polymers on fire retardancy. Oxygen index method was used to evaluate the fire retardancy of paints. The chlorinated alkyd resin was used as a plasticizer for laroflex MP 35 to improve the fire retardancy of the thermoplastic chlorinated polymer.
The purpose of this paper is to review the advances in mechanics and tribology of polymers and polymer-based materials. It is focused on the understanding of the…
The purpose of this paper is to review the advances in mechanics and tribology of polymers and polymer-based materials. It is focused on the understanding of the correlation of contact mechanics and the tribological behavior of polymers and polymer composites by taking account of surface forces and adhesion in the contact.
Mechanical behavior of polymers is considered a viscoelasticity. Tribological performance is estimated while considering the parts of deformation and adhesion in friction arising in the contact. Surface energy, roughness, load and temperature effects on the tribological behavior of polymers are evaluated. Polymer composites produced by reinforcing and by the addition of functional additives are considered as materials for various applications in tribology. Particular attention is given to polymer-based nanocomposites.
A review of studies in tribology has shown that polymer-based materials can be most successfully used as self-lubricating components of sliding bearings. The use of the fillers provides changes in the tribological performance of neat polymers and widens their areas of application in the industry. Thin polymer films were found to be prospective lubricants for memory storage devices, micro-electro-mechanical systems and precision mechanisms. Further progress in polymer tribology should be achieved on solving the problems of contact mechanics, surface physics and tribochemistry by taking account of the scale factor.
The review is based on the experience of the authors in polymer mechanics and tribology, their research data and on data of many other literature sources published in this area. It can be useful for specialists in polymer research and industrial engineers working in tribology and industrial lubrication.
Corrosion protection has long relied on a number of wet or dry processes including PVC, polyurethane, thermosetting polymer and thermoplastic coatings. Each of these have…
Corrosion protection has long relied on a number of wet or dry processes including PVC, polyurethane, thermosetting polymer and thermoplastic coatings. Each of these have weaknesses, either in the level of protection provided, durability, cost, or ease of application. The introduction of DuPont’s Abcite ethylene acid copolymer coating represents a major technology breakthrough as it offers a combination of properties with many advantages for a very wide range of applications.
A review of water‐based thermosetting resins for industrial finishes includes the fundamental parameters of acrylic polymers and a comparison of emulsion, colloid and…
Focusses on preliminary studies on developing thermoplastic composite materials suitable for use in fused deposition modeling (FDM). Looks at thermotropic liquid…
Focusses on preliminary studies on developing thermoplastic composite materials suitable for use in fused deposition modeling (FDM). Looks at thermotropic liquid crystalline polymers (TLCPs). Specifically aims to determine the feasibility of post‐processing TLCP composite strands generated by means of the dual extrusion process using FDM to enhance the tensile properties and functionality of prototypes. Describes the experiments and gives in‐depth results which include the finding that final mechanical properties of a composite prototype can be tailored to a specific application by adjusting the laydown pattern to increase the functionality of the prototype, and that these properties can be predicted by composite theory.