Metal-filled polymers

Metal-Filled Polymers Properties and Applications, edited by Swapan K. Bhattacharya... 

Battacharya, S. K., ed. (1986) Metal Filled Polymers, New York, Marcel Dekker. 

Kusy, R.P. (1986) Applications, Chapter 1, in Metal-Filled Polymers Properties and Applications (ed. S.K. Bhattacharya), Marcel Dekker, Inc., New York. 

Vysotsky V.V., and Roldughin VI. Aggregate structure and percolation properties of metal-filled polymer films. Coll. Surf. Part A. 160 no. 2 (1999) 171-180. 

Many types of LGA sockets (also referred to as interposers) are available. There are interposers with traditional dimpled leaf-spring contacts, Fuzz Button contacts, and even metal-filled polymer contacts. The contacts are held on a molded insulating substrate. The contacts and socket frame are customized to fit the LGA package and corresponding PWB footprint (see Fig. 50.4). 

FIGURE 50.4 LGA sockets (a) a socket with metal-filled polymer contacts (b) a socket with Fuzz Button contacts (c) closeup of a single wire-wound Fuzz Button. 

If too much pressure is applied to metal-filled polymer contacts, they can deform and flow over time, lessening contact pressure, and result in open or intermittent contact failures. 

Natanson, E. M. and Ul berg, Z. R., Colloidal Metals and Metal-Filled Polymers, Naukova Dumka, Kiev, 1971, Chapts. 1-3. 

Source Bhattacharya SK (1986) Metal-filled polymers. Marcel Dekker,... 

Hansen D, Tomkiewicz R (1975) Heat conduction in metal-filled polymers the role of particle size, shape and orientatiotL Polym Eng Sd 15 353-356... 

Figure 1 shows the mechanism for current flow through a metal-filled polymer. If enough metal particles are added to form a network within the polymer matrix, electrons can flow across the particle contact points, making the mixture electronically conductive. Even under the most favorable circumstances, current flow occurs only over the small area of the contact points, so the conductivity of even the best current silver-filled products is two orders of magnitude lower than the conductivity through pure silver. 

Bigg, D. M. (1986). Electrical properties of metal-filled polymer composites. In S. K. Bhattacharya (Ed.), Metal-filled polymers (pp. 165 -226). Marcel Dekker, New York. 

---